feat: simplify HTTP client proxy pools and authenticated JSON calls

test: record remote configuration release acceptance
feat: unify generated configuration loading and extensible decoders
2026-09-26 15:28:19 +08:00 · 2026-09-26 14:49:28 +08:00 · 2026-09-26 14:47:33 +08:00 · 2026-09-25 17:31:48 +08:00 · 2026-09-25 17:27:28 +08:00 · 2026-09-25 13:58:45 +08:00
134 changed files with 10142 additions and 1673 deletions
--- a/AGENTS.md
+++ b/AGENTS.md
@@ -0,0 +1,8 @@
+# 开发约定
+
+- 框架保持通用，不内置接入项目的业务类型、字段、错误码或业务规则。
+- 2026-09-25 用户要求：每次功能开发完成，必须同步维护根 README.md。README 需要覆盖当前全部公开功能，解释用途、基本用法，并提供可运行示例或链接到 examples 内的完整示例。
+- 新增、调整和删除功能都必须同步文档、示例、测试与发布说明。删除功能要明确说明已移除内容、影响范围和迁移步骤，不能继续把历史用法当作当前能力推荐。
+- examples 使用通用场景，避免依赖业务项目、私有数据库或线上服务。必要的外部基础设施配置应明确说明。
+- 2026-09-25 用户决定：移除 mappings/mappingFiles 及结构映射代码生成机制，改用可选 copyx 工具包。不得恢复另一套 JSON 或 Go 映射声明语言。
+- 深拷贝的自定义转换结果不得与输入共享可变引用；发现共享应报错，不能降级成浅拷贝或静默接受。
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -1,5 +1,32 @@
 # Changelog

+## v0.21.0-preview（2026-09-26）
+
+- httpc 可配置环境/直连/固定代理、常用连接阶段超时和独立空闲池参数。
+- JSON 新增逐请求 Header 快照与响应大小选项，保持有界读取、关闭和认证隔离。
+- 成功请求少复制和退避计算，丢弃响应流式处理，错误体有界回收以改善连接复用。
+- 增加真实本地代理、超时、连接限制/回收、并发、日志脱敏、gzip、fuzz 和修改前后基准。
+- JSON 自定义方法接口签名需同步 variadic 参数；借用 Transport 的参数混配现在报错。详见 httpc/README.md。
+
+
+## v0.20.0-preview（2026-09-26）
+
+- 生成项目配置加载入口持续由生成器维护；保留业务字段、默认值、校验与 NewLoader 扩展文件。
+- config.LoadProject 统一 JSON/YAML/XML、环境覆盖和校验；提供实例级 Decoder 注册。
+- 文件/字段/环境/行列的安全诊断，Invalid/AtField 与原始错误链。
+- 增加格式等价、精度、null/空数组、并发、资源限制、默认值隔离、真实生成项目与性能验收。
+- 旧手写 Load 必须显式迁移；低层 API 保留。固定数组严格长度、YAML alias/merge/custom tag 拒绝。用法及限制见 CONFIG.md。
+
+
+## v0.19.0-preview（2026-09-25）
+
+- 新增通用可选 copyx：构造器、浅/深拷贝、精确类型转换、字段规则、nil/零值策略、并发复用。
+- 深拷贝拒绝自定义结果共享源可变引用；原子提交目标、保留错误链、限制遍历及估算分配。
+- 移除 JSON 结构映射配置与生成；提供明确迁移诊断，保留公共字段组合等其他生成能力。
+- 同步 README 全部能力索引、COPY.md、可运行示例和开发文档约定。
+- 验收与不兼容迁移见 [发布说明](RELEASE.md)、[copyx 验收](reports/copyxAcceptance.md)。v0.14–v0.18 的完整变更保留在发布说明历史段落。
+
+
 ## v0.13.0-preview（2026-09-24）

 - 新增通用 lifecycle.Controller，svc.RequestShutdown 支持依赖主动通知正常停止或致命故障，通知不阻塞，首个故障原因保留；生成入口排空 HTTP 后关闭依赖与日志，故障退出码为 1。
--- a/CONFIG.md
+++ b/CONFIG.md
@@ -0,0 +1,178 @@
+# 统一配置加载
+
+v0.20 起，新生成服务的 `main.go` 调用生成器维护的 `config.Load`。项目只需要定义业务字段、默认值和校验；日志、HTTP、数据库等配置使用同一流程，配置加载时不打开数据库、监听端口或创建日志文件。
+
+```text
+代码默认值 → envDefault（仅填零值）→ 可选配置文件
+→ 完整结构体环境覆盖（含别名）→ 框架规范化 → 项目 Validate
+→ 初始化日志及项目依赖 → 启动服务
+```
+
+## 生成项目要维护什么
+
+| 文件 | 维护方 | 用途 |
+| --- | --- | --- |
+| `main.go` | 生成器 | 启动、信号、请求排空、依赖关闭 |
+| `internal/config/loadGen.go` | 生成器 | 调用统一加载入口；纳入 `generate --check` |
+| `internal/config/config.go` | 项目 | `Config`、`Default()`、`Validate()` |
+| `internal/config/loader.go` | 项目 | `NewLoader()`，只有增加文件格式时才需修改 |
+| `etc/config.yaml` | 项目 | 部署配置；可改用 JSON/XML 并传 `-config` |
+| `internal/svc` | 项目与生成器分文件 | 初始化依赖、登记清理、AppOptions |
+
+比如增加业务的批次数量：在 Config 增加一个字段，在 Validate 加范围校验；需要部署值时改配置文件或环境变量。不修改 main、Load 或 Handler。
+
+```go
+// 添加到项目 Config。
+BatchSize int `json:"batchSize" envDefault:"100"`
+
+// 添加到项目 Validate。
+if c.BatchSize < 1 || c.BatchSize > 1000 {
+    return omniConfig.Invalid("batchSize", "must be between 1 and 1000")
+}
+```
+
+自动支持 `GO_OMNI_BATCH_SIZE`。生成服务的空环境值策略为 `ignore`，0 和 false 是有效覆盖；范围由 Validate 决定。
+重新生成保留 config.go、loader.go 和 svc 的手写扩展。
+
+## 手写项目用法
+
+```go
+package main
+
+import (
+    "time"
+    "git.yuntuo.hk/k2safe/go-omni/config"
+)
+
+type Config struct {
+    Timeout time.Duration `json:"timeout" envDefault:"3s"`
+    Limit   int           `json:"limit" envDefault:"100"`
+    Token   string        `json:"-" env:"APP_TOKEN,secret"`
+}
+func (c Config) Validate() error {
+    if c.Timeout <= 0 {
+        return config.Invalid("timeout", "must be positive")
+    }
+    return nil
+}
+
+// cfg, err := config.LoadProject("etc/config.yaml", Config{},
+//     config.EnvOptions{Prefix: "APP_", Empty: "reject"})
+```
+
+`LoadProject` 接收结构体默认值，可实现值接收器或指针接收器的 `Validate() error`。空路径表示不读文件。
+`DecodeFile` 只做文件覆盖，不做 envDefault、环境覆盖或业务 Validate；旧的两参数调用仍有效，可用结构体或结构体指针。低层 `ApplyDefaults`、`OverlayEnv`、`LoadFile` 继续存在。
+
+嵌套校验用 `config.AtField("client", err)` 加路径前缀。公共原因通过 `config.Invalid` 提供，原因中不要包含密码、DSN、Token 或输入原值。
+
+## JSON / YAML / XML
+
+按文件扩展名选择解析器：`.json`、`.yaml`、`.yml`、`.xml`，大小写不敏感。所有格式使用 Go 结构体的 **json 字段名**，无需为 XML 复制一份结构或标签。
+以下配置等价：
+
+```json
+{"client":{"timeout":"2s"},"enabled":false,"ports":[8080,8081],"optional":null}
+```
+
+```yaml
+client:
+  timeout: 2s
+enabled: false
+ports: [8080, 8081]
+optional: null
+```
+
+```xml
+<config>
+  <client><timeout>2s</timeout></client>
+  <enabled>false</enabled>
+  <ports type="array"><item>8080</item><item>8081</item></ports>
+  <optional type="null"/>
+</config>
+```
+
+XML 必须使用一个 `<config>` 根；普通叶节点按目标 Go 类型转换。数组显式 `type="array"` 加 `<item>`，不根据重复元素猜测类型。`type="array"` 空元素表示空数组，`type="object"` 表示空对象，`type="null"` 表示 null。`any` 中的 XML 叶节点默认是字符串，需要动态数字/布尔时标注 `type="number"` / `type="bool"`；也可用 `type="string"`。
+
+类型和覆盖规则：
+
+- 缺失字段保留默认值；显式 0、false、空字符串正常覆盖。
+- null 清空指针、map、slice、interface；普通值字段保持默认值，沿用 Go JSON 解码语义。需要区分 null 时用指针。
+- 数组整体替换；空 slice 保持非 nil；固定长度 Go 数组要求长度一致，避免丢弃多余配置。
+- map 合并键，已提供的键整体覆盖对应值；map 中未提供的键保留。
+- duration 支持 `250ms`、`3s`；整数保持精度，动态 JSON 数字使用 `json.Number`，不先转 float64。
+- 自定义 `json.Unmarshaler` / `encoding.TextUnmarshaler` 仍可接入。这些回调是可信项目代码，必须自己保证并发和副作用安全；不要修改共享外部状态。
+- JSON `,string` 字段、嵌入字段遵循 JSON 字段选择；未知字段、重复绑定、冲突均拒绝。
+
+内置解析器限制：单文件最多 1 MiB，解析最多 64 层、100000 个节点；绑定和默认值复制也有深度限制。只接受普通文件，不读取设备或命名管道。不支持多文档、重复字段、无效 UTF-8；YAML 拒绝 alias/merge/custom tag，XML 拒绝 DTD/外部实体、命名空间、业务属性和混合内容。XML 仅支持配置所需的子集，不是通用 XML 文档映射器。
+
+这些限制针对启动配置，避免意外超大文件、别名扩展和模糊覆盖。自定义值解码器的内部字段校验由该解码器负责；例如现有错误目录使用其专有解码规则。
+
+## 环境覆盖
+
+统一入口的 EnvOptions 控制前缀、空值策略、别名和 Lookup。完整 JSON 路径自动转换为 UPPER_SNAKE_CASE：`client.timeout` → `APP_CLIENT_TIMEOUT`。
+
+```go
+config.EnvOptions{
+    Prefix: "GO_OMNI_", Empty: "ignore",
+    Aliases: config.ServerEnvAliases("GO_OMNI_", "server"),
+}
+```
+
+生成项目同时接受完整的 `GO_OMNI_SERVER_HTTP_READ_TIMEOUT` 与短别名 `GO_OMNI_HTTP_READ_TIMEOUT`。完整名存在时优先，即便其空值被 ignore，也不回退别名。不会再二次调用 ApplyEnv 覆盖业务字段。
+
+显式 `env:"CUSTOM_NAME"` 是绝对名称；`env:"-"` 跳过子树。`json:"-"` 只在声明显式 env 名时参与，可让密钥只能从环境加载。`secret` 标签表达用途，解析错误对所有字段都不打印值。slice/map 的环境值采用 JSON。`required` 检查字符串非空、指针/集合非 nil；复杂范围由 Validate 负责。详见 [完整业务环境覆盖](DEVELOPMENT.md#完整业务配置的环境覆盖)。
+
+显式环境选择日志 stdout/stderr 会清除文件 profile 的 File/Rotation，除非同时提供非空 File 覆盖。该兼容规则由框架处理。
+
+## 扩展解析器
+
+内置格式直接可用。新增格式只在 `internal/config/loader.go` 的 `NewLoader` 注册：
+
+```go
+func NewLoader() (*omniConfig.Loader, error) {
+    return omniConfig.NewLoader(
+        omniConfig.WithDecoder("custom", omniConfig.DecoderFunc(
+            func(data []byte) (omniConfig.Document, error) {
+                // 演示注册扩展名；实际可在这里调用项目选定的 TOML 等解析库。
+                return (omniConfig.JSONDecoder{}).Decode(data)
+            },
+        )),
+    )
+}
+```
+
+Decoder 返回 Document：Value 是 map[string]any 根，子值为 string/bool/json.Number/nil/[]any/map[string]any；无自身类型的叶节点可返回 config.Text。Positions 可选，用 `client.timeout` 或 `servers[0].timeout` 标记 1-based 行列。不提供位置时仍有文件、字段、原因。
+
+自己的语法错误可返回 `&config.Error{Field: "client.timeout", Line: 3, Column: 5, Reason: "expected a duration"}`。Reason 必须安全；普通第三方错误仅公开 `invalid configuration syntax`，内部 cause 通过 errors.Is/As 保留。
+
+注册表属于 Loader 实例，无全局 init 注册；不能覆盖已有扩展名。Loader 可共享，但 Decoder 必须支持并发且不保留/修改输入。解析插件是可信 Go 代码，框架不是插件沙箱。新格式依赖由选择它的项目显式引入，核心不强制引入 TOML 等库。
+
+## 定位配置错误
+
+```text
+config "etc/config.yaml":4:12 field "client.timeout": expected a duration such as 5s
+config env "APP_CLIENT_TIMEOUT" field "client.timeout": expected a valid time.Duration
+```
+
+`errors.As(err, &diagnostic)` 可获取 `*config.Error` 的 File/Field/Env/Line/Column/Reason；原 `DecodeError` 名称保留为别名。`errors.Is` 可判断文件不存在等 I/O 原因。
+
+解析失败显示文件和可获取的行列；Validate 使用 Invalid/AtField 才能定位业务字段。环境覆盖导致的错误优先标环境变量，不错误地归因到文件；数组元素验证也会追溯到覆盖它的集合环境变量。默认值未出现在文件里时没有行列。YAML 语法错误通常只有行号，列显示 1。
+
+不打印底层错误原文或配置值；任意普通 `errors.New(...)` 校验失败的公开原因是 `validation failed`，内部原因仍在链中。项目应改用 Invalid 给出安全的原因。第三方子配置校验若没有字段元数据，只定位到对应子树，框架不会从任意错误文案猜字段。
+
+不要把 Unwrap 后的原始错误、整个配置对象写入公开日志/HTTP；自定义解析器与校验器传入的 Reason 由项目负责脱敏。
+
+## v0.19 及更早项目迁移
+
+先提交现有代码，再升级匹配的 CLI 与框架。旧项目的 `internal/config/config.go` 含手写 Load，新生成器会明确阻止 generate/check/dry-run，不会直接覆盖它。
+
+1. 保留 Config、Default、Validate、业务配置结构及辅助函数。
+2. 删除旧 Load。普通的 defaults/file/env/Validate 流程已由 LoadProject 接管；移除由此不再使用的 import。将自定义默认值和校验分别迁入 Default / Validate，自定义文件格式迁入 NewLoader。
+3. 框架只在 `loader.go` 不存在时创建 NewLoader；已有项目文件同名时需要保证它提供同签名函数。无需手写 loadGen.go。
+4. 重新生成，执行 `generate --check`、`go test ./...`、`go build .`，再用真实配置验证启动。
+
+保留业务需要的显式 env 标签/规则；如果原 Load 有解密或其他项目特殊步骤，不要直接删除，应先明确其归属，必要时在自定义 Decoder 中处理。生成器不自动搬动或猜测手写行为。`api upgrade` 仍可预览较早版本的基础设施差异，但已修改的配置必须按上述步骤迁移。
+
+不会移除低层配置 API；本次移除的是**新项目里重复手写的加载流程**，不删除旧项目的业务文件。
+
+完整可运行例子：[examples/configuration](examples/configuration/README.md)。
--- a/COPY.md
+++ b/COPY.md
@@ -0,0 +1,141 @@
+# 可选拷贝工具 copyx
+
+v0.19 用普通 Go 调用取代 JSON 结构映射生成。`copyx` 只依赖标准库，不需要注册到 App，不执行 JSON 往返，也不会自动暴露数据库模型。普通 Logic 直接使用 `.api` 生成的 DTO；只有存在独立业务类型或需要隔离可变数据时才用它。
+
+完整可运行代码：[examples/copying](examples/copying)。在框架根目录运行：
+
+```sh
+go run ./examples/copying
+go test -race ./copyx ./examples/copying
+```
+
+## 最简单的调用
+
+```go
+import "git.yuntuo.hk/k2safe/go-omni/copyx"
+
+type Request struct { Name string; Enabled bool }
+type Input struct { Name string; Enabled bool }
+
+req := Request{Name: "sample", Enabled: false}
+var input Input
+if err := copyx.Copy(&input, req); err != nil { return err }
+```
+
+同名、同类型字段直接赋值。默认不会跳过 `false`、`0`、空字符串。目标字段没有来源时报错；多余源字段默认忽略，使用 `WithStrictFields()` 可要求源字段也全部使用或显式忽略。
+
+默认是浅拷贝：同类型指针、map、slice 共享引用，符合普通 Go 赋值。JSON tag 不参与字段匹配。不会自动调用方法、SQL Scanner/Valuer，或把 `int32`、`int64`、string、命名标量互相强转。
+
+新字段：普通接口只改 `.api` 和使用该字段的 Logic。独立 DTO/业务类型都需要此字段时，两边各声明一次；同名同类型不增加拷贝配置。检查在运行时发生，实际类型对必须有测试，不能把运行时工具当作旧生成器的编译期字段覆盖检查。
+
+## 深拷贝与构造器
+
+```go
+snapshot, err := copyx.Clone(source) // 保持源的静态类型，始终深拷贝
+if err != nil { return err }
+
+copier, err := copyx.New(copyx.WithDeepCopy(), copyx.WithStrictFields())
+if err != nil { return err }
+var result Output
+if err := copier.Copy(&result, source); err != nil { return err }
+```
+
+`Copy` 的目标必须是非 nil 指针；`Clone[T]` 返回 `(T, error)`。重复执行时在初始化阶段创建 Copier 并复用；配置之后不可变，每次调用独立持有遍历状态，可以并发使用。源、目标的并发读写仍由调用方同步，自定义函数也须支持并发。
+
+深拷贝会分配指针、map、slice，递归处理结构、数组、接口中的具体值。nil 集合与非 nil 空集合保持区别；slice 结果容量为长度，不复制长度之外的隐藏元素。普通循环和重复指针可处理。循环图应保留根指针，使用 `Clone(sourcePointer)` 或 `Copy(&targetPointer, sourcePointer)`；将循环指针根压成值结构会明确报错。
+
+它保证结果不引用输入中的可变对象，不保证保留所有底层内存布局关系：不同重叠 slice 视图会分别复制，内部指针指向某个切片元素的关系也不重建。字符串和零尺寸值可安全共享；`time.Time` 按 Go 不可变值使用（Location 不做独立复制）。不要通过 unsafe 或 uintptr 隐藏可变引用后要求工具识别。
+
+## 字段差异与自定义转换
+
+```go
+type Input struct { Name string; UpdatedAt time.Time; InternalID string }
+type View struct { DisplayName string; UpdatedAt string; LocalNote string }
+
+copier, err := copyx.New(
+    copyx.WithDeepCopy(),
+    copyx.WithStrictFields(),
+    copyx.WithFieldNames[Input, View](map[string]string{"Name": "DisplayName"}),
+    copyx.WithIgnoreSource[Input, View]("InternalID"),
+    copyx.WithIgnoreTarget[Input, View]("LocalNote"),
+    copyx.WithConverter(func(v time.Time) (string, error) {
+        return v.UTC().Format(time.RFC3339), nil
+    }),
+)
+if err != nil { return err }
+out := View{LocalNote: "preserve"}
+if err := copier.Copy(&out, input); err != nil { return err }
+```
+
+字段规则的类型参数必须是结构类型，字段名使用导出的 Go 字段名。构造时检查不存在的字段、重名及冲突。不支持字符串路径表达式；复杂嵌套差异为该嵌套类型注册 converter，或直接写 Go。
+
+`WithIgnoreSource` 只是声明该源字段不参与使用；目标同名字段若仍需保留，还需 `WithIgnoreTarget`。忽略目标会保留原目标值，Clone 中则为零值。深拷贝时如果保留值仍与源共享可变引用，也会拒绝。
+
+转换器的签名是 `func(S) (T, error)`，按**精确类型对**匹配，不能重复注册。金额、编号、日期格式由项目明确转换。需要逐字段不同规则时，给整个源/目标结构注册函数；函数返回独立的新目标。无需另一份映射配置或全局注册。
+
+精确 converter 优先于 nil/零值策略，能收到 typed nil；例如 `func(*Money) (Money, error)` 可自行决定 nil 是否允许。绑定到 `any` 字段的 converter 能接收 nil interface，但顶层未带类型的 `nil` 没有精确类型可匹配。浅拷贝中已经直接共享的同类型容器不会继续逐项转换其内部；需要遍历内部时选择深拷贝，或为该容器类型注册 converter。
+
+## 深拷贝不能原样返回可变引用
+
+```go
+copier, err := copyx.New(
+    copyx.WithDeepCopy(),
+    copyx.WithConverter(func(v []string) ([]string, error) {
+        return v, nil // 会返回 ErrSharedReference
+    }),
+)
+```
+
+检查覆盖完整源图与转换结果，包括新父对象引用旧子对象、原 map、重叠子切片、`source[:0]` 的可写容量、指向源数组元素的指针，以及未导出字段中的引用。会检查每个 converter 的结果和最终目标，不允许静默降级为浅拷贝。
+
+返回相同字符串、整数并不会报错，它们不是可变引用。正确切片 converter 可以写：
+
+```go
+copyx.WithConverter(func(v []string) ([]string, error) {
+    if v == nil { return nil, nil }
+    out := make([]string, len(v))
+    copy(out, v)
+    return out, nil
+})
+```
+
+第三方 Decimal/自定义 Money 如果含未导出的指针，默认深拷贝拒绝；注册该类型的 converter，使用它自己的构造/Clone API 创建独立值，避免转成 float64 损失精度。框架不内置某一金额库的规则。无法独立复制的类型直接返回错误。
+
+## nil、零值和错误
+
+| 选项 | 行为 |
+| --- | --- |
+| 默认 `NilError` | nil → 可空目标保留 nil；nil → 非可空目标报 `ErrNil` |
+| `WithNilPolicy(NilZero)` | 显式允许 nil → 零值；可空目标仍为 nil |
+| `WithNilPolicy(NilSkip)` | nil 保留已有目标；新集合元素没有旧目标，保留元素零值 |
+| `WithSkipZero()` | 显式跳过 Go 零值，包括 `false`、`0`、`""`；非 nil 空集合不是 Go 零值 |
+
+所有 nil 策略都不把不兼容类型自动变成兼容类型。非 nil 指针与值之间可以按对应元素转换；nil 到非可空目标仍需选择策略。局部更新不能默认使用 NilZero/SkipZero，它们可能改变清空字段或布尔值的业务语义。
+
+工具只能复制绑定后的 Go 值：如果输入类型已经将“缺失”和“JSON null”合并为 nil，无法恢复两者区别。需要三态时，应先设计包含 presence 信息的类型和绑定逻辑。
+
+赋值使用临时结果，成功后才替换目标；转换失败不会交付部分结果。`*copyx.Error` 包含 Go 字段/索引路径，`errors.Is/As` 保留内部错误链，工具不主动在错误中加入源值。converter 自己返回的错误文本仍由项目负责。
+
+converter 必须只读输入；其外部副作用、输入修改无法回滚，panic 原样传播。框架只检查与本次输入的共享引用，无法证明 converter 未返回外部全局缓存的引用。它是受信 Go 代码扩展，不是可运行不可信代码的沙箱。
+
+## 支持范围与资源限制
+
+- 支持结构体、指针、interface、slice、同长度 array、map。map key 转换后冲突或不可比较则报错。
+- 导出匿名结构字段可按提升后的无歧义名称访问；源嵌入指针为 nil 且需要其字段时明确报错。跨类型目标包含私有字段时拒绝；同类型私有纯值可作为整体保留。
+- 不克隆文件、数据库连接、网络连接、锁、原子状态。已知标准库资源/同步结构按值复制也拒绝；深拷贝中的非 nil func、chan、unsafe.Pointer 拒绝。其他封装资源类型应由项目排除，工具不能识别所有自定义句柄。
+- 单次遍历深度上限 256、节点上限 200,000；内置分配的估算预算为 64 MiB，超限返回 `ErrLimit`。预算不是进程堆内存硬限制，reflect 元数据和 converter 自行分配不计入。大对象流式读写应使用 IO/存储接口。
+- 只缓存不可变类型元数据，不缓存请求值、用户 converter 或实例策略。没有 `unsafe` 写入、JSON 往返、隐式数值截断或方法调用。
+- 这是运行时反射工具，会比直接 Go 赋值多检查与分配。热点应复用 Copier，并用真实数据测量；性能记录见 [本版验收](reports/copyxAcceptance.md)。
+
+## 从旧 mapping 迁移
+
+v0.19 **彻底移除**映射配置加载、Go 类型加载、映射代码生成及 `pointerResult` 等附属选项。公共 `.api` 字段组合、scalar、中间件工厂、Repository 开关继续存在。
+
+1. 先检查每个转换是否必要。普通 Logic 可直接使用生成 DTO；独立核心保留自己的类型。
+2. 将 `mapping.Xxx(...)` 调用改为普通 Go 或小型 `copyx` helper。字段改名、nil、金额规则写在该 helper 同一处。指针返回可直接 `var out *Response; err := copier.Copy(&out, input)`。
+3. 用真实类型对测试缺失/null/零值/空数组、字段覆盖、金额精度和错误链。需要源字段新增时提醒遗漏，启用 `WithStrictFields()` 并测试。
+4. 从 `omni.gen.json` 删除 `mappings` / `mappingFiles`，删除无其他用途的映射 JSON 文件。
+5. 确认已无调用，再删除 `internal/mapping/mappingsGen.go`。如之前手改过文件，先迁出手写内容。生成器遇到该旧文件会阻止生成并提示迁移，**不会静默删除**；其余业务文件照常保留。
+6. 升级框架与 CLI 到同版，执行 generate、generate --check、go test ./...；多个服务再执行 workspace generate/check。新 manifest 自动去掉已移除文件的所有权记录。
+
+历史发布记录保留旧能力说明，仅用于理解旧版本，不代表 v0.19 继续支持。
--- a/DEVELOPMENT.md
+++ b/DEVELOPMENT.md
@@ -1,7 +1,9 @@
-# 通用业务开发指南（v0.15.0-preview）
+# 通用业务开发指南（v0.21.0-preview）

 从 [README](README.md) 创建服务后，业务主要维护 `.api`、配置、`svc.Init`、Logic、Repository 和项目中间件。本页说明通用接入能力；字段、错误码、权限、表结构和事务边界都由项目定义。

+公共字段组合、自动中间件工厂和 Repository 开关，见 [生成能力指南](GENERATION.md)。必要的结构转换使用可选 [copyx](COPY.md)，v0.19 已移除旧 JSON 映射生成。
+
 ## 返回数组、可空对象和 null

 ```text
@@ -21,12 +23,17 @@ delete /item
 | 契约 | Logic 返回 | 成功数据 |
 | --- | --- | --- |
 | `returns (Item)` | `(*types.Item, error)` | 对象；nil 被视为实现错误 |
-| `returns ([]Item)` | `([]types.Item, error)` | 数组；nil 统一输出 `[]` |
+| `returns ([]Item)` | `([]types.Item, error)` | 对象数组；nil 统一输出 `[]` |
+| `returns ([]string)` | `([]string, error)` | 字符串数组 |
+| `returns ([]int64)` / `([]bool)` | `([]int64, error)` / `([]bool, error)` | 数值 / 布尔数组 |
+| `returns ([]any)` | `([]any, error)` | 动态 JSON 数组，元素允许对象、数组、标量和 null |
 | `returns (*Item)` | `(*types.Item, error)` | 对象或 `null` |
 | `returns (null)` | `error` | HTTP 200 和空业务数据 |
 | 不写 returns | `error` | HTTP 204，无响应体 |

-统一响应中的空数据是否显示，仍遵循项目模板的 `dataMode`；需要 `data:null` 就设置 `dataMode: always`。`@response raw` 输出业务数据本身，包括 `[]`、对象或 `null`。可用 `@status 201/202`；204 不能声明响应类型。根类型当前支持以上四种形式，嵌套字段继续支持既有 slice/map/pointer/scalar/any。
+统一响应中的空数据是否显示，仍遵循项目模板的 `dataMode`；需要 `data:null` 就设置 `dataMode: always`。`@response raw` 输出业务数据本身，包括 `[]`、对象或 `null`。可用 `@status 201/202`；204 不能声明响应类型。嵌套字段继续支持既有 slice/map/pointer/scalar/any。
+
+基础类型数组还支持 int/int8/int16/int32、uint/uint16/uint32/uint64、float32/float64。nil 根数组都输出 `[]`；`[]any` 在 OpenAPI 中是 `type: array, items: {}`，不限制元素形状，但元素必须可被标准 JSON 编码器序列化。`[]uint8`（Go 的 byte slice）会编码为 base64，故明确拒绝；数字数组可用 `[]int32`，二进制用下载接口。当前不支持根嵌套数组或根自定义 scalar 数组。

 ## 契约驱动的请求策略

@@ -95,7 +102,9 @@ defer reader.Close()

 ## 完整业务配置的环境覆盖

-生成项目默认执行：代码与 `envDefault` 默认值 → JSON/YAML 文件 → 全结构体环境覆盖 → 既有框架环境别名 → `Validate`。增加业务字段不需要另外写 `os.Getenv`。
+生成器维护 `internal/config/loadGen.go`；项目维护 Config/Default/Validate 和可选 NewLoader。三种格式、可扩展解析器、字段错误定位及旧 Load 迁移见 [统一配置指南](CONFIG.md)。
+
+生成项目默认执行：代码与 `envDefault` 默认值 → JSON/YAML/XML 文件 → 全结构体环境覆盖（含别名）→ 规范化 → `Validate`。增加业务字段不需要另外写 `os.Getenv`。

 ```go
 type ClientConfig struct {
@@ -113,6 +122,23 @@ duration 使用 `250ms`、`3s`；slice/map 使用 JSON，如 `[1,3,5]`、`{"retr

 手写项目可使用 `config.LoadProject(path, defaults, config.EnvOptions{Prefix:"MY_APP_"})`，或分别调用 `ApplyDefaults/DecodeFile/OverlayEnv`。读取失败不修改输入默认值；诊断不会打印输入值。不要主动打印含密钥的整个配置，或把底层解析错误展开到公开响应。Validate 不打开日志文件、数据库或存储连接；证书的可读性和握手信任在依赖初始化阶段验证。

+### 一次覆盖完整配置与 HTTP/日志短名称
+
+```go
+cfg, err = config.OverlayEnv(cfg, config.EnvOptions{
+    Prefix: "MY_APP_",
+    Empty: "reject", // allow / ignore / reject，项目自行选择
+    Aliases: config.ServerEnvAliases("MY_APP_", "server"),
+    // Lookup 可注入测试或项目配置源；默认 os.LookupEnv。
+})
+```
+
+不要再紧接着调用 `ApplyEnv(cfg.Server, ...)`。上面的调用同时处理完整配置和 HTTP_ADDR、SERVICE、LOG_LEVEL 等框架短名称。例如 `MY_APP_SERVER_ADDRESS` 与 `MY_APP_HTTP_ADDR` 指向同一字段，**完整名称优先**；未设置时才读取短名称。完整名称显式设空仍优先：allow 交给该字段解析（string 可清空；数字等仍要求合法值），ignore 保留文件/默认值，reject 报错。不会因 ignore 再退回别名。字段 `env` 标签的 empty 规则优先于全局规则。
+
+自定义别名用 `EnvOptions.Aliases`，键是完整环境名、值是按优先级排列的别名数组。两种名称都使用同一 Lookup、空值策略和类型转换；布尔 false、数值 0 与未设置不同。集合始终使用 JSON，包括 `MY_APP_TRUSTED_PROXIES='["127.0.0.1"]'`。
+
+新项目模板一次调用 OverlayEnv，默认 `Empty: "ignore"`。旧 `ApplyEnv` 保留原有忽略空值、修剪空白及 TRUSTED_PROXIES 逗号列表行为。已有项目的 `internal/config` 属于开发者文件，升级不覆盖它；按上例合并原来的两次覆盖调用后，保留项目自己的 Validate。日志输出的显式完整名称也优先于短名称。
+
 ## 依赖、日志与中间件

 `internal/svc/runtimeGen.go` 持续由生成器维护。项目的 ServiceContext 嵌入 `*lifecycle.Runtime`，只在 `Init(ctx)` 中装配额外依赖：
@@ -123,40 +149,15 @@ func (c *ServiceContext) Init(ctx context.Context) error {
    if err != nil { return err }
    c.Client = client
    c.OnClose(client.Close)
-    c.Middlewares["RequireAccess"] = middleware.NewRequireAccess(client)
    return nil
 }
 ```

 每个资源初始化成功就登记清理；后续初始化失败自动逆序回滚。正常退出先排空 HTTP 请求，再执行后台组件的 Stop/Drain 阶段，确认收尾后逆序关闭依赖，最后关闭日志。关闭幂等，单个清理函数 panic/返回错误不会跳过其他清理；初始化 panic 清理后继续传播。后台组件按 [分阶段关闭](lifecycle/README.md#后台组件分阶段关闭) 登记；无法确认收尾完成时保留共享依赖并异常退出，不能把取消等同于任务已经结束。

-中间件用业务所需的小接口接收依赖，避免反向导入 svc：
+新项目使用中间件工厂：项目维护 `middleware.Dependencies` 小接口与 `New<Name>(deps) (httpx.Middleware, error)`，svc 提供对应访问器。生成的 runtime 在 Init 成功后自动调用工厂并注册，不再按名字替换 map；工厂失败会释放已经登记的依赖。示例与现有项目迁移步骤见 [中间件工厂](GENERATION.md#中间件工厂自动注册)。

-```go
-// internal/middleware/accessFactory.go
-package middleware
-
-import (
-    "context"
-    "git.yuntuo.hk/k2safe/go-omni/httpx"
-)
-
-type AccessChecker interface {
-    CheckAccess(context.Context, string) error
-}
-func NewRequireAccess(checker AccessChecker) httpx.Middleware {
-    return func(next httpx.Handler) httpx.Handler {
-        return func(c *httpx.Context) error {
-            if err := checker.CheckAccess(c.Context(), c.Header("Authorization")); err != nil {
-                return err
-            }
-            return next(c)
-        }
-    }
-}
-```
-
-`.api` 声明对应 middleware 后，保留生成的初始 hook，并另建上述工厂；在 Init 用工厂替换 registry 的同名项即可。该包只依赖接口和 HTTP 抽象，不导入 svc，也不把数据库藏到 context 里。
+v0.16 项目及 `omni.gen.json` 中选择 `middleware: handlers` 的项目继续使用原有 `Defaults()`，可以在 Init 设置 `c.Middlewares["RequireAccess"]`。更新时不会重写这部分业务代码；只有显式切换到 factories 后才使用新流程。

 生成入口为每个 App 注入独立 Logger，不修改进程默认 Logger。业务可用 `c.Logger.InfoContext(...)`，或请求链中的 `logx.InfoContext(ctx,...)`。标准库/第三方需要 `*log.Logger` 时使用 `c.Logger.Standard(slog.LevelWarn)`；适配器借用原 Logger，不负责关闭。手写多 App 用 `omni.WithLogInstance(logger)` 显式注入。

@@ -185,21 +186,9 @@ go-omni api generate --check

 格式化保留注释、token 和多行字面量，规范四空格缩进、空行、行首尾空白及相邻单行字段的类型/标签/行尾注释对齐；结果幂等。先校验完整契约，check 不写文件；导入的共享目录不被某个服务的格式化命令修改。DTO 按源 `.api` 输出 `dto<Source><摘要>Gen.go`，都属于 `types` 包，跨文件引用无需改包名。

-Go Catalog 是错误的唯一来源时，显式导出文档元数据：
+Go Catalog 是错误的唯一来源时，优先使用 workspace 的显式导出配置，不再维护导出/复制脚本。AppOptions 仍通过 `omni.WithErrors(apierrors.Catalog())` 注册同一个 Go 函数，运行期只注册一次。单个项目也可继续使用 `errors.ExportCatalog` 导出入口目录的 `api/omni.errors.json`；此文件和下面的共享 source 二选一。

-```go
-// 在项目自己的导出命令中；appErrors.Catalog 与 AppOptions 注册同一函数。
-if err := omnierrors.ExportCatalog(os.Stdout, appErrors.Catalog()); err != nil {
-    log.Fatal(err)
-}
-```
-
-```sh
-go run ./cmd/exportErrors > api/omni.errors.json
-go-omni api generate
-```
-
-文件是派生产物，应纳入版本控制并由业务 CI 检查导出漂移。CLI 自动读取入口目录的 `omni.errors.json`，校验错误目录、合并状态/模板参数/具体示例到 OpenAPI；不会运行项目 Go，不创建另一份运行期注册器。带独立错误目录的路由继续使用自己的目录。没有路由级精确错误列表时，文档描述 App 目录的公共错误集合；特殊自定义 Encoder 的文档由项目显式扩展。
+OpenAPI 自动把有收益的重复响应、schema 和示例移到 `components.responses/schemas/examples`，通过标准 `$ref` 引用。HTTP 200 同时含成功和业务失败时保留两种 schema、业务码、模板参数示例和 data:null；业务响应内容不会改变。消费 OpenAPI 的工具需要支持标准本地引用。

 ## 两个服务共享契约

@@ -241,9 +230,57 @@ go-omni workspace check --file omni.workspace.json

 各服务保持独立 module；可显式填写各服务的 `api`（相对服务目录）和 `module`。所有服务预检通过后再写；每个服务独立提交文件事务，不承诺跨项目的崩溃原子性。check 汇总格式与生成漂移；业务编译/测试仍在各 module 执行。

+### 同一份 Go 错误目录供多个服务生成
+
+在 workspace 清单显式声明提供目录的 Go 包和函数：
+
+```json
+{
+  "errorCatalogs": [{
+    "dir": ".",
+    "package": "example.com/project/internal/apierrors",
+    "function": "Catalog",
+    "output": "contracts/common/errors.json"
+  }],
+  "services": [{"dir":"services/api"}, {"dir":"services/id"}]
+}
+```
+
+`dir` 相对 workspace，必须包含 go.mod；函数签名为 `func Catalog() errors.Catalog`。允许 module 内的 internal 包。先准备 output 的父目录。生成器构建一个临时导出程序，使用 Go overlay、临时 go.mod/go.sum 和 `-mod=readonly`，不会往项目增加导出命令或修改 go.mod/go.sum。最多 16 个提供方，每个有 90 秒构建/执行总时限和 1 MiB stdout 限制。错误消息不回显程序输出。
+
+只有显式运行 **workspace generate/check** 会执行清单指定的 Go 包及其依赖初始化；不要指向不信任的包。提供目录的函数应只构造目录，不连接数据库、启动服务、写 stdout 或修改项目。框架不扫描其他包，也不通过 shell 执行配置字符串。普通 api validate/export/generate 和 workspace format 只读取现有元数据。
+
+各服务在自己的 `api/omni.imports.json` 引用共享 JSON：
+
+```json
+{
+  "roots": {"common":{"path":"../../../contracts/common","version":"1.0.0"}},
+  "errors": {
+    "source": "@common/errors.json",
+    "include": ["USERNAME_INVALID", "INTERNAL_ERROR"],
+    "routes": {"GET /permissions":["INTERNAL_ERROR"]}
+  }
+}
+```
+
+`include` 省略或 null 表示全部目录，`[]` 表示不列业务错误；routes 按 **大写方法 + 空格 + .api 原路径**（如 `GET /users/:id`）覆盖服务级列表。错误标识、路由拼错或重复标识会明确报错。路由已经通过 `.api @errors` 声明独立运行期目录时，不能再给它设置文档 routes 列表。
+
+**这些列表只决定文档展示，不修改 App 错误目录、路由继承或运行期可返回的错误。** `.api` 不需要重复定义 Go 错误表。状态、业务码、提示和模板参数仍来自同一 Catalog；特殊自定义 Encoder 的文档由项目显式扩展。
+
+```sh
+# 首次生成导出一次共享目录，所有服务预检通过才写入
+# 共享 JSON 不复制到各服务；已有 api/omni.errors.json 请显式移除后改用 source。
+go-omni workspace generate --file omni.workspace.json
+go-omni workspace format --file omni.workspace.json
+go-omni workspace generate --file omni.workspace.json
+go-omni workspace check --file omni.workspace.json
+```
+
+共享 JSON 应纳入版本控制。check 在内存重新导出并比较 JSON，然后检查所有服务；缺失或过期时失败，不更新项目文件。Go 构建缓存仍可能更新；显式提供方的自有副作用不属于生成器可隔离范围。业务 CI 仍执行各 module 的编译与测试。目录函数本身有变化时重新 generate，受控共享根的固定 SHA256 如需改变仍由项目显式更新。
+
 ## v0.13 项目升级

-先使用与目标框架匹配的 CLI；CLI 会提示与 go.mod 不同的版本。当前生成模板至少需要 v0.15.0-preview（或显式引用当前源码）。
+先使用与目标框架匹配的 CLI；CLI 会提示与 go.mod 不同的版本。当前生成模板至少需要 v0.20.0-preview（或显式引用当前源码）。

 ```sh
 go-omni api upgrade --dir . --dry-run
--- a/GENERATION.md
+++ b/GENERATION.md
@@ -0,0 +1,116 @@
+# 公共字段、中间件工厂与生成选项
+
+本页对应 `v0.19.0-preview`。CLI 与框架依赖固定到同一版本，安装见 [README](README.md#准备环境与安装)。
+
+## 一份项目生成配置
+
+新项目根目录的 `omni.gen.json` 只描述生成选项：
+
+```json
+{
+  "repository": "none",
+  "middleware": "factories"
+}
+```
+
+- `repository: none` 默认不创建空 Repository 文件；`group` 按 group 补齐可编辑骨架。已有文件始终保留；切回 none 不会删除业务文件。SQL、ORM 和仓储划分由项目决定。
+- `middleware: factories` 是新项目默认值，自动调用带依赖的工厂。`handlers` 保留原有 `Defaults()` 及手动注册方式，供既有项目迁移。
+- 该文件与 `.api` 一起提交。generate/check/dry-run 和 workspace 采用相同规则；validate/export/format 只处理接口契约。
+- 旧 manifest 没有配置时补 `middleware: handlers`、`repository: none`。已有配置不能直接删除，避免意外切换中间件模式。
+- v0.19 已删除 `mappings` 和 `mappingFiles`；遇到旧配置会明确报错，不读取子映射文件或执行映射生成。处理步骤见 [copyx 迁移](COPY.md#从旧-mapping-迁移)。
+
+## 公共字段组合
+
+```text
+type EmployeeFields {
+    // 员工姓名。
+    Name string `json:"name" binding:"max=80"`
+    Salary Money `json:"salary"`
+}
+
+type EnterpriseRequest {
+    EmployeeFields
+}
+
+type AdminRequest {
+    EmployeeFields
+    CompanyID string `path:"companyId"`
+}
+```
+
+`Money` 由项目按既有 scalar 语法声明。组合行只有已声明的对象类型名，不加指针或字段 tag。公共对象可以通过已有相对 import 或声明过的共享根 `@common/...` 引入。
+
+生成器展开为普通 Go 字段。JSON 保持平铺；字段的绑定来源、校验、注释、可空性和 OpenAPI 使用同一份展开结果。不会在 JSON 中增加 `EmployeeFields` 一层。重复 Go 字段、重复来源字段名、循环组合、未知对象和过深展开均失败；即使重复字段类型相同，也不能隐式覆盖。要改变某个字段的规则，应拆出更小的公共组合。
+
+允许多层组合，上限 32 层、单类型 4096 字段、全契约展开 65536 字段。Go 匿名指针嵌入并非本功能；生成 DTO 中不会使用匿名嵌入。
+
+## DTO 与业务类型
+
+普通 Logic 直接接收生成的 Request、返回生成的 Response，不额外创建相同结构。只有独立核心或明确不同的输入/输出职责才保留业务类型。
+
+必要转换直接写 Go，或用可选 `copyx.Copy(&target, source)`。同名同类型字段自动赋值，字段改名和类型变化通过 Go 参数、转换函数明确设置，见 [完整示例](examples/copying/main.go)。无需 JSON 映射配置、包路径字符串或额外生成文件。
+
+`copyx` 在运行时检查类型和字段，**不提供旧映射生成阶段的静态字段覆盖保证**；CI 应给实际类型对添加测试。普通业务字段新增通常只改 `.api` 和 Logic；独立 DTO/领域类型都需要此字段时，两边各加一次，同名同类型无需追加拷贝配置。
+
+## 中间件工厂自动注册
+
+`.api` 沿用 `middleware: RequireAccess` 或 auth 对应的中间件声明。新项目会生成可编辑的 `internal/middleware/requireAccessFactory.go`，只需实现一次：
+
+```go
+// internal/middleware/dependencies.go，由项目维护。
+type AccessChecker interface {
+    CheckAccess(context.Context, string) error
+}
+type Dependencies interface {
+    AccessChecker() AccessChecker
+}
+
+// internal/middleware/requireAccessFactory.go，由项目维护。
+func NewRequireAccess(deps Dependencies) (httpx.Middleware, error) {
+    checker := deps.AccessChecker()
+    if checker == nil { return nil, errors.New("access checker is required") }
+    return func(next httpx.Handler) httpx.Handler {
+        return func(c *httpx.Context) error {
+            if err := checker.CheckAccess(c.Context(), c.Header("Authorization")); err != nil {
+                return err
+            }
+            return next(c)
+        }
+    }, nil
+}
+
+// internal/svc/access.go，由项目维护；ServiceContext.Init 初始化 c.Auth。
+func (c *ServiceContext) AccessChecker() middleware.AccessChecker { return c.Auth }
+```
+
+编译器检查 ServiceContext 是否实现依赖接口，middleware 不导入 svc。多个工厂可以共用这些小接口。所需 imports 和具体鉴权服务仍属于项目。
+
+启动顺序为：框架基础依赖 → `svc.Init` → 生成的 `middleware.New(c)` 调用各具名工厂 → 创建 App/注册路由 → 监听。中间件实例创建一次，由请求并发复用；不要把单次请求信息存在实例字段里。工厂之间没有初始化顺序依赖；路由执行顺序仍以 `.api` 声明为准。
+
+工厂返回错误或 nil 中间件均阻止监听；错误链保留，已登记资源按现有生命周期清理。工厂 panic 也先清理依赖再传播。资源初始化和清理登记放在 svc.Init，工厂借用资源；HTTP 请求排空之前不会关闭这些依赖。
+
+factory 模式不再在 Init 写 `Middlewares["..."]`；残留非空手写注册表会明确报错，防止生成注册静默覆盖它。未实现的工厂让启动失败；未实现的 Logic 仍返回 501。
+
+### 既有项目迁移
+
+1. 首次更新保持 `middleware: handlers`，现有 hook 和手写 Configure 不变。
+2. 改为 factories 并重新生成，会补 `dependencies.go` 和 `*Factory.go`，保留原来的手写文件。
+3. 将旧实现迁入工厂，提供 Dependencies 的访问器；移除 Init 中按名字覆盖 map 的代码。
+4. 旧函数不再需要时由项目删除。若新工厂符号与旧文件中的同名函数冲突，整理旧文件；生成器不覆盖业务代码。
+5. `generate --check` 与 `go test ./...` 检查后再运行。工厂没有全部实现前，服务不会启动。
+
+## 文件维护边界
+
+| 项目维护 | 生成器持续维护 |
+| --- | --- |
+| `.api` 公共字段与接口 | 展开后的 DTO、Handler、OpenAPI |
+| `omni.gen.json` 的 Repository/中间件选项 | 对应骨架和注册代码；已有手写骨架不覆盖 |
+| 独立 Go 业务类型、scalar、可选 copyx 调用和测试 | 不生成结构转换文件 |
+| middleware Dependencies、具名工厂、svc 访问器 | 中间件 registry、启动调用 |
+| Logic、Repository、配置、svc 初始化/清理登记 | main、runtime、路由接入 |
+
+独立三端工资契约测试位于 `cmd/go-omni/apigen/testdata/composition`，不导入任何接入项目。它验证公共字段、Money scalar、三端 Handler、copyx、重新生成保留业务内容，以及新增字段不需要更新转换规则。
+
+```sh
+GO_OMNI_SCAFFOLD_INTEGRATION=1 go test ./cmd/go-omni/apigen -run TestCopyxThreeEndpointConsumer -count=1
+```
--- a/MODULES.md
+++ b/MODULES.md
@@ -6,6 +6,24 @@
 [examples/modules](examples/modules/README.md)。业务入口继续使用 `omni.New`，中间件依赖
 `httpx`，不依赖具体服务端网络实现。各模块按需创建、注入 Service，再注册到应用关闭流程。

+## 请求追踪与基础指标
+
+`omni.New()` 的默认链包含 RequestID、访问日志（可配置开关）和 Recovery；无需重复挂载。业务通过 `c.Context()` 传递 requestId，`logx.FromContext(ctx)` 取得该 App 的 Logger。手动组装 httpx 链时，也可使用 `middleware.RequestID("X-Request-ID")`、`middleware.AccessLog()` 和 `middleware.Recovery()`。
+
+轻量进程指标直接使用 `metrics`，无需 OTel collector：
+
+```go
+// import omni "git.yuntuo.hk/k2safe/go-omni"
+// import "git.yuntuo.hk/k2safe/go-omni/metrics"
+app := omni.New()
+measurements := metrics.New()
+app.Use(measurements.Middleware())
+app.GET("/metrics", measurements.Handler())
+// 也可以直接读取 measurements.Snapshot()。
+```
+
+记录请求数、失败数、处理中数量、累计耗时与 HTTP 状态分布；返回的是 JSON 快照，并非 Prometheus 文本格式。指标接口是否暴露以及访问权限由项目配置。需要 HTTP/SQL/Redis spans 和标准 OTel exporter 时，使用 [telemetry 示例](examples/platform/main.go)。CORS 由项目中间件或代理配置，当前没有内置 CORS 模块。
+
 ## 缓存：cache 与 cache/redis

 ```go
@@ -52,30 +70,26 @@ application.OnShutdown(client.Close)

 ```go
 client, err := httpc.New(httpc.Config{
-    Timeout: 3*time.Second, MaxRetries: 2, MaxConnsPerHost: 32,
-    MaxResponseBytes: 1 << 20,
+    Proxy: httpc.ProxyConfig{Mode: httpc.ProxyDirect},
+    Timeout: 3*time.Second, DialTimeout: time.Second,
+    TLSHandshakeTimeout: time.Second, ResponseHeaderTimeout: time.Second,
+    MaxConnsPerHost: 32, MaxIdleConnsPerHost: 16, MaxIdleConns: 64,
+    IdleConnTimeout: 60*time.Second, MaxResponseBytes: 1<<20,
 })
 if err != nil { return err }
 application.OnShutdown(client.Close)
-err = client.JSON(ctx, "GET", serviceURL, nil, &result)
+err = client.JSON(ctx, "GET", serviceURL, nil, &result,
+    httpc.WithHeader("Authorization", "Bearer "+token),
+)
 ```

-客户端应在服务启动时创建并复用。默认使用独立的 `net/http.Transport` 连接池，每个目标主机
-有连接上限；该上限不是整个进程的全局连接数上限。也可以注入自有 `http.RoundTripper`，
-其连接限制和生命周期由调用方负责。这样出站实现同样可以替换。
+启动时创建并复用 Client。代理可选环境、直连、固定地址；不配置时保留标准库原代理策略。JSON 支持单次请求头和响应限额，不保存 Client 全局 Token。新阶段超时与空闲连接参数可选，0 沿用默认。

-总超时覆盖建连、重试、等待和读取响应体。`Do` 返回后调用方必须读取/关闭 `response.Body`；
-`JSON` 自动关闭，并限制解码前读取的字节数。`Do` 允许流式读取，本身不限制响应体大小。
-`Close` 拒绝新请求、关闭自有池的空闲连接；在途请求应先排空。
+成功响应读取有界；output=nil 流式丢弃，不整体缓存。小错误体只在大小/时间预算内尝试读完以复用连接；未知或大错误体及时关闭。Do 保留标准流式 Request/Response，由调用者限量读取并关闭 body。Close 拒绝新调用并关闭自有池空闲连接，项目先排空在途工作。

-`MaxRetries` 默认 0，最多 5。封装只对可重放的 GET/HEAD/OPTIONS 重试网络错误及
-429/502/503/504；POST/PUT/PATCH/DELETE 不做应用层自动重试。标准库 Transport 和借用的
-RoundTripper 自身的重放规则仍生效，不能据此承诺“只执行一次”。退避带抖动，尊重
-`Retry-After`；服务器要求等待超过 `MaxBackoff` 时直接返回该响应，不提前重试。
-重定向交给业务处理，3xx 不会自动跟随。
+自定义 Transport 借用、不修改、不关闭；不能同时指定池/代理/阶段选项。总超时持续覆盖 HTTP 等待、重试和读取 body，但不抢占 JSON 编解码或不遵守 context 的自定义代码。MaxRetries 默认 0，只对可重放 GET/HEAD/OPTIONS 重试；3xx 不跟随。标准库和借用 Transport 自身仍可能重放，不能据此承诺业务只执行一次。

-默认从 context 传递 `X-Request-ID`，日志只包含方法、主机、状态、尝试次数和收到响应头的耗时，
-不记录完整 URL、查询参数、凭证和响应体。非 2xx 的 JSON 调用返回只带状态码的 `StatusError`。
+完整参数、NO_PROXY、TLS、安全日志、重试、签名兼容说明见 [httpc 指南](httpc/README.md)，可运行 [HTTP Client 示例](examples/httpClient/README.md)。

 ## 请求保护：middleware

--- a/PROJECT.md
+++ b/PROJECT.md
@@ -1,6 +1,6 @@
 # 生成项目与文件维护边界

-v0.15.0-preview 提供受管理的生成项目。安装同版远程 CLI，生成的项目直接引用该版本，无需本地 replace。根目录入口支持 `go run .` 和 `go build .`；框架本身仍然是可直接引用的库。安装和私有仓库访问见 [README](README.md#准备环境与安装)。
+v0.21.0-preview 提供受管理的生成项目。安装同版远程 CLI，生成的项目直接引用该版本，无需本地 replace。根目录入口支持 `go run .` 和 `go build .`；框架本身仍然是可直接引用的库。安装和私有仓库访问见 [README](README.md#准备环境与安装)。

 ## 创建和日常开发

@@ -38,27 +38,32 @@ ERROR [logicSignature] internal/logic/greet/greet.go:12 (GET /api/greet/:name):

 这是轻量源码分析，不运行项目 init、不执行 Go 命令、不下载依赖。项目自定义类型别名、嵌入方法或 build tags 等无法可靠判断时，会给 REVIEW 并交给 Go 编译器验证；不把这些情况强行判为签名错误。它不检查方法体是否引用已删除字段，也不证明业务逻辑正确。CI 中应同时执行 `go-omni api generate --check` 和 `go test ./...`，按项目实际构建参数测试。当前版本首次接手缺少快照的 manifest v2 时，会明确提示建立基线，不猜测旧契约；Logic 签名检查仍会执行。

+生成选项、公共字段组合和可选 Go 拷贝工具，详见 [生成能力指南](GENERATION.md)。
+
 ## 哪些文件由用户维护

 | 文件 | 首次生成后由项目维护 |
 | --- | --- |
 | `api/*.api` | 路由、DTO、具名中间件、响应模板、请求/响应模式 |
 | `etc/config.yaml` | 运行参数；密钥通过环境变量提供 |
-| `internal/config/config.go` | 自定义配置字段、加载、默认值与校验 |
+| `internal/config/config.go` | 自定义配置字段、默认值与校验 |
+| `internal/config/loader.go` | 需要额外文件格式时注册 Decoder |
 | `internal/svc/serviceContext.go` | 依赖字段和初始化，持有加载后的 Config |
 | `internal/svc/options.go` | AppOptions、GlobalMiddleware；注册 Go 错误目录和全局扩展 |
 | `internal/svc/databaseOptions.go` | 可选 MySQL 驱动与项目启动检查扩展 |
 | `internal/svc/storage.go` | 选用存储时生成，之后保留 |
 | `internal/logic/<group>/*.go` | 业务方法，使用标准 context.Context |
-| `internal/repository/<group>/*.go` | 数据访问，按需实现 |
-| `internal/middleware/<name>.go` | 项目鉴权/权限等具名中间件实现 |
+| `internal/repository/<group>/*.go` | 数据访问；默认不补空骨架，可选 group 模式 |
+| `internal/middleware/*Factory.go`、`dependencies.go` | 中间件工厂与依赖小接口，svc 实现访问器 |
+| `omni.gen.json` | Repository 和中间件生成选项；不再声明结构映射 |
+| 可选的 Go 转换函数 / copyx 调用 | 只有独立类型确实需要转换时维护，见 [copyx](COPY.md) |
 | 项目 Go 错误包 | 自行维护 Catalog 和常量，可跨服务共用 |
 | 自定义标量文件、`*Bind.go`、`*Manual.go` | 只有显式选择相应扩展时才生成/使用 |
 | 项目测试、迁移、部署脚本、go.mod/go.sum | 项目所有，生成器不重置其内容 |

 以上骨架只补缺失文件，既有内容按字节保留。删除已废弃接口后，对应业务文件也不会被自动删除；由开发者整理编译器指出的失效类型或签名。

-生成器持续管理：`internal/svc/runtimeGen.go`、`main.go`、`internal/handler/*Gen.go`、分组的 `handlersGen.go`、`internal/types/*Gen.go`、中间件 `registryGen.go`、`docs/openapi.json`、`.goOmni/apiManifest.json`。如果在 `.api` 里选择声明错误，还会管理 `internal/apierrors/errorsGen.go`。文件标注 DO NOT EDIT；手改会被拒绝覆盖，需先移走自定义内容。
+生成器持续管理：`internal/config/loadGen.go`、`internal/svc/runtimeGen.go`、`main.go`、`internal/handler/*Gen.go`、分组的 `handlersGen.go`、`internal/types/*Gen.go`、中间件 `registryGen.go`、`docs/openapi.json`、`.goOmni/apiManifest.json`。如果在 `.api` 里选择声明错误，还会管理 `internal/apierrors/errorsGen.go`。文件标注 DO NOT EDIT；手改会被拒绝覆盖，需先移走自定义内容。

 Logic 实例在注册时创建并由请求并发复用；请求数据用方法参数和局部变量传递，不存入共享 Logic/svc 字段。

@@ -85,7 +90,7 @@ func (c *ServiceContext) AppOptions() []omni.Option {
 }
 ```

-业务调用 `omnierrors.ByCode(apierrors.CodeUsernameInvalid)`，可接 `WithParams` / `WithCause`。无需在 `.api` 重复错误目录。未声明独立错误目录的路由继承 App 目录；独立目录不与 App 合并。静态 OpenAPI 不执行 Go；可从同一 Catalog 显式导出 `api/omni.errors.json`，详见 [元数据导出](DEVELOPMENT.md#字段文档格式化go-错误目录导出)。
+业务调用 `omnierrors.ByCode(apierrors.CodeUsernameInvalid)`，可接 `WithParams` / `WithCause`。无需在 `.api` 重复错误目录。未声明独立错误目录的路由继承 App 目录；独立目录不与 App 合并。普通 `.api` 编译不执行 Go；可在 workspace 显式配置 Catalog 函数，统一导出共享文档元数据，也可沿用 `api/omni.errors.json`，详见 [元数据导出](DEVELOPMENT.md#字段文档格式化go-错误目录导出)。

 `GlobalMiddleware()` 提供全局中间件；`Middlewares` 映射提供 `.api` 声明的具名中间件。全部显式调用，不依赖项目 init 注册，也不要求 svc 导入 handler。框架请求链按原有次序运行。

@@ -110,6 +115,8 @@ c.RequestShutdown(err)

 `Lifecycle *lifecycle.Controller` 是 svc 持有的通用控制器，初始化时创建，生成入口使用它的 Context。该 Context 表示服务正在停止，不代表数据库已经关闭。不能把它当作在途请求的 Context，也不要在它取消时立刻关闭请求仍依赖的资源。发号器失去租约后拒绝发号等业务安全规则仍由项目实现。

+配置加载入口 `internal/config/loadGen.go` 也由生成器维护。业务扩展 Config/Default/Validate；只有新格式才需要修改 NewLoader。JSON/YAML/XML、错误定位和旧 Load 迁移见 [配置指南](CONFIG.md)。
+
 ## 配置内置接口

 生成项目在 `etc/config.yaml` 明确列出以下默认配置；可以独立关闭、修改路径，或让健康接口返回原始 JSON：
@@ -208,7 +215,7 @@ get /download (DownloadReq)

 ## 已有服务接入步骤

-每个独立服务生成一个项目，module 名称、上层目录和共享业务包由项目选择。接入时固定 CLI 与框架版本为 v0.15.0-preview：
+每个独立服务生成一个项目，module 名称、上层目录和共享业务包由项目选择。接入时固定 CLI 与框架版本为 v0.21.0-preview：

 1. 先保留旧服务，整理实际路由及现有响应、鉴权和超时要求。在新目录执行 `go-omni new --api /path/to/service.api --module example.com/service ./service`；不对旧入口强制覆盖。
 2. 在 `.api` 中选择 `@app(defaultResponse: ...)`，显式保留原项目的字段、成功码、错误码和 `dataMode`。需要独立回执的路由单独声明 raw/produces。普通路由、404/405 和提前返回的中间件一起验收。
--- a/README.md
+++ b/README.md
@@ -2,18 +2,106 @@

 GoOmni 是面向多个业务项目复用的 Go 后端框架：用 `.api` 定义接口、请求和返回类型，生成项目目录、HTTP 接入代码及 OpenAPI，业务代码负责 Logic 和 Repository。也可以在已有项目中直接使用 `omni.New()`，或单独引入日志、存储等模块。

-**从这份 README 开始接入。** 当前版本 **`v0.15.0-preview`**，新生成项目采用根目录入口和 `config / svc / logic / handler`。可以固定版本开展业务接入；文件维护边界和已有服务迁移步骤见 [项目指南](PROJECT.md)，版本变化与验收见 [发布说明](RELEASE.md)。
+**从这份 README 开始接入。** 当前版本 **`v0.21.0-preview`**，新生成项目采用根目录入口和 `config / svc / logic / handler`。可以固定版本开展业务接入；文件维护边界和已有服务迁移步骤见 [项目指南](PROJECT.md)，版本变化与验收见 [发布说明](RELEASE.md)。
+
+**v0.19 改动**：新增可选 `copyx` 工具，用普通 Go 调用完成浅拷贝、深拷贝和显式类型转换；深拷贝会拒绝自定义转换中残留的源对象可变引用。**移除了 `mappings` / `mappingFiles` 和映射代码生成**，已有使用者须按 [迁移步骤](COPY.md#从旧-mapping-迁移) 调整，不能直接删除仍在调用的旧文件。
+
+普通接口的流程是：**修改 `.api` → 生成 Request/Response → 写 Logic → 测试**。有独立职责的业务类型才需要转换；可直接写 Go，也可以按需使用 [copyx](COPY.md)。公共字段组合、中间件工厂、Repository 开关继续支持，见 [生成能力指南](GENERATION.md)。

 Go **1.22+**。框架不依赖 Gin，默认使用标准库网络层，提供可切换的 native HTTP/1.1 和实验性 HTTP/2 适配器。

 响应字段、业务码、登录方式、权限规则和数据库表结构由接入项目决定。文中的 `code/msg/data`、`200/9999` 都是示例配置，可以替换。

-新增通用开发能力见 [业务开发指南](DEVELOPMENT.md)：数组/null、严格请求策略、声明式上传、完整配置环境覆盖、资源生命周期、共享契约和升级工具。MySQL 直接使用 [官方适配器](database/mysql/README.md)。
+契约支持 `returns([]string/[]int64/[]bool/[]any)`、OpenAPI 公共引用、workspace 一次导出共享 Go 错误目录，以及统一环境变量别名覆盖。详细配置与升级步骤见 [业务开发指南](DEVELOPMENT.md)。
+
+已有通用开发能力见 [业务开发指南](DEVELOPMENT.md)：数组/null、严格请求策略、声明式上传、完整配置环境覆盖、资源生命周期、共享契约和升级工具。MySQL 直接使用 [官方适配器](database/mysql/README.md)。

 后台组件可在 svc 登记 [分阶段关闭](lifecycle/README.md#后台组件分阶段关闭)，先停止接收工作并等待收尾，再关闭共享资源；无需绑定队列或 ORM。

 使用 GORM 的项目可以选择 [gormx 适配器](database/gormx/README.md)，复用数据库初始化和连接池，并将 SQL 日志接入 logx。

+## 当前功能与使用入口
+
+下表是当前公开能力的索引。每项给出调用入口和完整说明；模块按需使用，`omni.New()` 不会自动初始化数据库、Redis、ORM、队列或云存储。示例中的 import 统一以 `git.yuntuo.hk/k2safe/go-omni/` 开头。
+
+| 功能与用途 | 怎么用 | 解释与示例 |
+| --- | --- | --- |
+| 项目、接口与文档生成 | `go-omni new`；改 `.api` 后 `api generate`；`--check` 检查漂移 | [下方快速开始](#新项目生成并运行)、[CLI](cmd/go-omni/README.md)、[完整生成项目](examples/managedService/README.md) |
+| 公共字段与跨服务共享契约 | `.api` 组合对象字段；`omni.imports.json` 声明共享根；workspace 批量生成 | [公共字段示例](GENERATION.md#公共字段组合)、[共享契约与 workspace](DEVELOPMENT.md) |
+| 中间件依赖工厂、可选 Repository | `omni.gen.json` 选择 factories / none；在 `New<Name>(deps)` 写一次实现 | [配置与完整工厂示例](GENERATION.md) |
+| 路由、分组、请求上下文 | `omni.New()`、`app.GET` / `Group` / `Use`；业务使用 `context.Context` | [基本服务](examples/basic/main.go)、[已有项目接入](#已有项目按模块接入) |
+| HTTP 网络与扩展适配 | 配置 transport 为 nethttp / native / http2；自定义 Router/Runner | [网络层配置与契约](transport/README.md)、[性能与限制](PERFORMANCE.md) |
+| HTTP 老接口桥接 | 通过官方 Handler/Middleware 适配器接入标准 `net/http`，跟踪实际响应状态 | [接入说明](MIGRATION.md)、[桥接/上传/自定义 ID 示例](examples/compatibility/main.go) |
+| 请求校验、动态 JSON、自定义标量 | `.api` 声明来源/校验/scalar；手写契约用 `contract.New[T]`；简单绑定可用 `validate.JSON/Query/URI` | [语法与例子](API.md)、[请求策略](DEVELOPMENT.md) |
+| 数组、null、原始请求、上传下载 | `.api` 声明数组/可空返回、body/multipart 与大小限制；必要时使用 Bind/Manual 扩展 | [契约示例](examples/contracts)、[含上传/回调/下载的项目](examples/managedService/README.md) |
+| 公共响应与特殊协议 | `.api` 定义 response 并 `@app(defaultResponse: ...)`；Go 用 `WithResponse` / Encoder | [响应配置](RESPONSE.md)、[响应模板契约](examples/contracts/responses.api) |
+| 错误目录与动态提示 | `WithErrors(catalog)` 注册一次；`ByCode(...).WithParams(...).WithCause(err)` | [错误目录](errors/README.md)、[模板参数示例](examples/contracts/errorParams.api) |
+| OpenAPI 与错误公共引用 | `.api` 自动生成；手写接口可使用 `openapi` 注册器；Go 错误目录显式导出 | [契约工具](DEVELOPMENT.md)、[注册示例](examples/platform/main.go) |
+| 结构化业务日志 | `logx.Info/Error`、`logx.FromContext(ctx)`、`logx.New`；支持轮转、脱敏、慢请求和级别更新 | [下方日志示例](#日志)、[完整配置](logx/README.md) |
+| 文件配置与环境覆盖 | 默认值→JSON/YAML/XML→环境→校验；完整业务结构用 `config.LoadProject[T]` / 环境别名 | [统一配置指南](CONFIG.md)、[完整可运行示例](examples/configuration/README.md)、[动态级别](ADVANCED.md#配置与日志热更新) |
+| 生命周期与健康检查 | svc 登记 OnClose/OnStop/OnDrain，RequestShutdown 通知故障；健康路径/开关可配 | [生命周期用法](lifecycle/README.md)、[健康检查](health/README.md)、[生成项目扩展](PROJECT.md) |
+| 数据库、连接池与事务 | `database.Open` / `OpenConnector`；事务与检查由项目显式调用 | [通用数据库](database/README.md)、[MySQL TLS/Logger](database/mysql/README.md) |
+| 可选 GORM 与迁移 | gormx 复用已有连接池；`go-omni migrate` 预览，显式 apply | [GORM 示例](database/gormx/README.md)、[迁移用法](ADVANCED.md#迁移审计与分页) |
+| 认证与权限接口 | 注入 Authenticator / Policy；JWT 或 Session 只是可选实现 | [认证说明](auth/README.md)、[鉴权完整例子](examples/platform/README.md) |
+| 缓存 | `cache.NewMemory` 或 Redis 实现；业务面向 Store 的 Get/Set/Delete | [缓存配置/代码](MODULES.md)、[可运行模块服务](examples/modules/README.md) |
+| 出站 HTTP、熔断 | `httpc.New` 配置代理、连接池和阶段超时；JSON 支持单次请求头/限额；`resilience.New` 隔离故障 | [HTTP 完整用法](httpc/README.md)、[可运行示例](examples/httpClient/README.md)、[熔断/观测](ADVANCED.md#熔断与观测) |
+| 请求追踪、访问日志、恢复、限流、幂等、超时 | `app.Use(...)` 按需组合 middleware；跨副本选择 Redis 实现 | [模块说明与限制](MODULES.md#请求追踪与基础指标)、[分布式实现](ADVANCED.md#分布式限流与幂等) |
+| 本地后台任务与调度 | `task.New`、Submit、Every；有界队列、排空关闭 | [task 示例与生命周期](MODULES.md#后台执行task) |
+| 持久队列 | 业务使用 Publisher / Consumer；Redis Streams 提供至少一次交付 | [队列初始化/消费示例](ADVANCED.md#可靠队列) |
+| 文件存储、直传、云端分片 | Store 的 Put/Get/Delete；Local、S3/R2、OSS 按配置装配；扩展接口提供分片续传 | [存储接口与完整例子](storage/README.md)、[本地存储服务](examples/platform/README.md) |
+| 日志关联、指标与链路 | `metrics.New().Middleware()`；telemetry 注入 OTel exporter/reader | [基础指标](MODULES.md#请求追踪与基础指标)、[OTel 用法](ADVANCED.md#熔断与观测)、[完整接入](examples/platform/main.go) |
+| 审计与分页 | `audit.New` 注入 Sink/白名单；`pagination.Parse` / `NewResult` | [解释与调用例子](ADVANCED.md#迁移审计与分页) |
+| 可选结构转换与深拷贝 | `copyx.Copy` / `Clone` / `New`；Go converter 处理差异 | [下方示例](#可选结构转换与深拷贝)、[完整 copyx 指南](COPY.md)、[可运行代码](examples/copying) |
+| 自定义适配器验收 | `transporttest.Run`、`storagetest.Run` / `RunUploads` 验证扩展契约 | [网络契约测试入口](transport/transporttest/router.go)、[存储契约测试入口](storage/storagetest/contract.go) |
+
+## 带认证的出站 HTTP
+
+HTTP Client 在 svc 初始化一次，业务重复使用。普通内部请求可直接选择直连和连接参数，无需手写 Transport：
+
+```go
+client, err := httpc.New(httpc.Config{
+    Proxy: httpc.ProxyConfig{Mode: httpc.ProxyDirect},
+    Timeout: 3*time.Second, DialTimeout: time.Second,
+    TLSHandshakeTimeout: time.Second, ResponseHeaderTimeout: time.Second,
+    MaxConnsPerHost: 32, MaxIdleConnsPerHost: 16, MaxIdleConns: 64,
+})
+if err != nil { return err }
+// 在 svc 生命周期登记 client.Close；关闭前先排空使用它的工作。
+err = client.JSON(ctx, "GET", endpoint, nil, &result,
+    httpc.WithHeader("Authorization", "Bearer "+token),
+    httpc.WithMaxResponseBytes(64<<10),
+)
+```
+
+请求头只作用于本次调用，不把用户 Token 留在共享 Client。默认代理/参数保持原行为；也可选择环境代理或固定代理。JSON 自动关闭并限制响应，Do 保留下载/流式读取扩展。完整配置、重试边界和已有自定义 Transport 的迁移见 [httpc](httpc/README.md)。
+
+```sh
+go run ./examples/httpClient
+```
+
+## 统一配置加载
+
+新生成项目的加载流程由框架管理。业务在 `internal/config/config.go` 增加字段、默认值和 `Validate`，无需改 main 或复制环境变量解析。JSON、YAML、XML 共用字段和校验；扩展格式在 `loader.go` 注册。
+
+```go
+// 项目 Config 中增加字段，自动支持 GO_OMNI_BATCH_SIZE：
+BatchSize int `json:"batchSize" envDefault:"100"`
+
+// 项目 Validate 中增加业务范围检查：
+if c.BatchSize < 1 {
+    return omniConfig.Invalid("batchSize", "must be positive")
+}
+```
+
+错误包含文件、字段、可用的行列或环境变量名；输入原值不自动写入错误。
+
+```sh
+go run ./examples/configuration -format xml
+DEMO_CLIENT_TIMEOUT=500ms go run ./examples/configuration
+```
+
+详见 [统一加载、解析器、迁移](CONFIG.md) 和 [完整示例](examples/configuration/README.md)。**旧项目须先迁移手写 Load，再重新生成**；生成器会保留业务配置并拒绝冲突，不静默覆盖。
+
 ## 选择接入方式

 | 你的项目 | 从哪里开始 |
@@ -34,7 +122,7 @@ module 地址是 `git.yuntuo.hk/k2safe/go-omni`。先确保本机 Go 和 Git 可

 ```sh
 export GOPRIVATE="$(go env GOPRIVATE),git.yuntuo.hk"
-go install git.yuntuo.hk/k2safe/go-omni/cmd/go-omni@v0.15.0-preview
+go install git.yuntuo.hk/k2safe/go-omni/cmd/go-omni@v0.21.0-preview
 export PATH="$(go env GOPATH)/bin:$PATH"
 go-omni --help
 ```
@@ -75,21 +163,22 @@ hello/
 ├── api/service.api                  # 维护接口定义，也可 import 其他 .api
 ├── main.go                          # 生成器维护：启动、路由注册、优雅退出
 ├── etc/config.yaml                  # 项目配置
+├── omni.gen.json                    # 项目维护的生成选项与可选映射
 ├── internal/
 │   ├── config/                      # 配置读取
 │   ├── svc/                         # 数据库、日志、外部客户端等依赖
 │   ├── types/*Gen.go                # 按 .api 文件生成 DTO
 │   ├── handler/                     # 生成的绑定、响应策略、路由及文档
 │   ├── logic/greet/                 # 在这里实现业务逻辑
-│   ├── repository/greet/            # 在这里实现数据访问
-│   └── middleware/                  # 声明鉴权等中间件后生成对应 hook
+│   ├── repository/                  # 按需创建，默认不生成空骨架
+│   └── middleware/                  # 声明鉴权等中间件后生成工厂
 ├── docs/openapi.json                # 生成的 OpenAPI 3.0.3
 └── .goOmni/apiManifest.json         # 生成文件所有权与校验信息，一起提交 Git
 ```

 修改 `api/service.api` 后重新生成，业务写在 `internal/logic`，数据访问写在 `internal/repository`，依赖在 `internal/svc` 装配。声明业务错误后还会生成 `internal/apierrors/errorsGen.go`。

-`api new` 的问候接口可以直接运行；自定义接口新生成的 Logic 和鉴权 hook 返回 **501**，需要实现后才可用。生成器不会根据 HTTP 字段猜数据库表或业务规则。
+`api new` 的问候接口可以直接运行；自定义接口未实现的 Logic 返回 **501**。新项目的具名中间件工厂未实现时直接阻止启动；v0.16 的原有 handler 模式仍返回 501。生成器不会根据 HTTP 字段猜数据库表或业务规则。

 ### 从自己的接口定义生成

@@ -190,7 +279,7 @@ go-omni new --api catalog.api \
 在业务项目的 **go.mod 所在目录**执行：

 ```sh
-go get git.yuntuo.hk/k2safe/go-omni@v0.15.0-preview
+go get git.yuntuo.hk/k2safe/go-omni@v0.21.0-preview
 ```

 已有项目可直接复用现有目录、Service、Repository 和数据库连接，先选择一个接口接入。也可以只用 `logx`、`storage` 等包，暂时保留原来的 HTTP 框架。希望入口和 HTTP 接入都交给生成器的项目，按 [已有服务接入步骤](PROJECT.md#已有服务接入步骤) 在新目录生成后迁入业务代码。
@@ -314,7 +403,7 @@ auth UserAuth (
 )
 ```

-生成器会创建 `internal/middleware/auth.go`，由项目实现凭据校验和身份注入。声明会生成路由绑定与 OpenAPI 的认证描述，**不会自动实现登录或授权规则**；未实现的 hook 返回 501。手写路由可使用 `auth.RequireAuth(authenticator)` 或自己的中间件。JWT、Session 和 Policy 按需选择。
+新项目生成 `internal/middleware/authFactory.go`，由项目实现 `NewAuth(deps)`；生成器负责初始化和注册。v0.16 或 handler 模式继续使用 `internal/middleware/auth.go`。凭据校验和身份注入由项目实现。声明会生成路由绑定与 OpenAPI 的认证描述，**不会自动实现登录或授权规则**；未实现的工厂阻止启动，原有 hook 模式返回 501。手写路由可使用 `auth.RequireAuth(authenticator)` 或自己的中间件。JWT、Session 和 Policy 按需选择。

 业务错误可以集中定义，业务只选择发生了哪个错误。**HTTP 状态由项目配置，业务失败可以返回 HTTP 200**；框架不根据 HTTP 状态单独判断成功与否。

@@ -384,6 +473,38 @@ return apierrors.TextTooLong("企业名称", 100)

 更详细的配置、作用域和升级步骤见 [统一错误目录](errors/README.md)。

+### 可选结构转换与深拷贝
+
+普通接口不需要任何拷贝配置，直接使用生成的 Request/Response。独立业务结构之间有转换需求时：
+
+```go
+// import "git.yuntuo.hk/k2safe/go-omni/copyx"
+var input DomainInput
+if err := copyx.Copy(&input, req); err != nil { return err }
+
+// 源与目标之间的指针、map、slice 需要隔离时：
+snapshot, err := copyx.Clone(source)
+if err != nil { return err }
+```
+
+默认浅拷贝，同名同类型字段自动赋值，保留零值；默认不会把 nil 填成非可空目标的零值。不要为使用工具新增一套重复模型。
+
+需要重复使用或自定义规则时创建 Copier：
+
+```go
+copier, err := copyx.New(
+    copyx.WithDeepCopy(),
+    copyx.WithFieldNames[Input, View](map[string]string{"Name": "DisplayName"}),
+    copyx.WithConverter(func(v time.Time) (string, error) {
+        return v.UTC().Format(time.RFC3339), nil
+    }),
+)
+if err != nil { return err }
+if err := copier.Copy(&view, input); err != nil { return err }
+```
+
+自定义函数的源/目标类型由 Go 泛型确定。深拷贝时返回原指针、原 map、子切片或嵌套旧引用都会报错；字符串/整数原值可以返回。差异规则、nil 策略、字段覆盖、资源限制和原 mapping 移除步骤见 [copyx 指南](COPY.md)，完整类型及可运行代码见 [examples/copying](examples/copying/main.go)。工具使用运行时检查，类型对需测试；深拷贝不适用于连接、锁等资源。
+
 ### 数据库、存储及其他模块

 生成项目在 `internal/svc` 中创建依赖，提供给 Logic/Repository，并用 `c.OnClose(db.Close)` 登记自有资源。生成的 main 在 HTTP 排空后关闭 svc，再关闭日志。直接使用框架的手写项目则可以用 `app.OnShutdown(db.Close)`；不要对同一资源重复登记。
@@ -458,9 +579,9 @@ go-omni api generate --check
 go test ./...
 ```

-`main.go`、`Gen.go`、`docs/openapi.json` 和 manifest 由生成器管理，手动修改会报告冲突。Logic、Repository、中间件实现、配置和依赖装配属于项目，重复生成保留手写内容。契约变化会提示受影响的 Logic 文件和 DTO 字段，明确的签名错误会给出原签名与期望签名；生成后 `--check` 仍能检出未修复的问题。将 `.api`、生成文件和 `.goOmni/apiManifest.json` 一起提交，CI 同时运行 `generate --check` 与 `go test ./...`。详见 [契约变更提示与检查边界](PROJECT.md#契约变更提示)。
+`main.go`、`Gen.go`、`docs/openapi.json` 和 manifest 由生成器管理，手动修改会报告冲突。Logic、Repository、中间件实现、配置和依赖装配属于项目，重复生成保留手写内容。契约变化会提示受影响的 Logic 文件和 DTO 字段，明确的签名错误会给出原签名与期望签名；生成后 `--check` 仍能检出未修复的问题。将 `.api`、`omni.gen.json`、生成文件和 `.goOmni/apiManifest.json` 一起提交，CI 同时运行 `generate --check` 与 `go test ./...`。详见 [契约变更提示与检查边界](PROJECT.md#契约变更提示)。

-CLI 与业务 module 固定使用 `v0.15.0-preview`。v0.14.x 项目升级依赖与 CLI 后重新生成，框架维护的 main/runtimeGen 自动更新；v0.13 及更早项目按 [升级预览](DEVELOPMENT.md#v013-项目升级) 处理，不直接覆盖手写入口或业务文件。升级后执行生成检查与业务回归。版本变化、迁移边界和验收记录见 [发布说明](RELEASE.md)。
+CLI 与业务 module 固定使用 `v0.21.0-preview`。v0.14–v0.19 项目先按 [配置入口迁移](CONFIG.md#v019-及更早项目迁移) 整理旧 Load，再升级依赖与 CLI 并重新生成，框架维护的 main/runtimeGen 自动更新；v0.13 及更早项目按 [升级预览](DEVELOPMENT.md#v013-项目升级) 处理，不直接覆盖手写入口或业务文件。使用过旧 mapping 的项目必须先完成 [移除迁移](COPY.md#从旧-mapping-迁移)，旧配置或旧生成文件会阻止生成。升级后执行生成检查与业务回归。版本变化、迁移边界和验收记录见 [发布说明](RELEASE.md)。

 ## 按需深入

@@ -476,3 +597,7 @@ CLI 与业务 module 固定使用 `v0.15.0-preview`。v0.14.x 项目升级依赖
 | 网络性能、测试条件与适用范围 | [性能说明](PERFORMANCE.md)、[HTTP/2 验收](transport/native/HTTP2.md) |

 当前版本可用于固定版本接入与业务验证，仍标记为 preview。`.api` 借鉴 go-zero 的接口开发方式，支持范围以本仓库文档为准，不是完整 goctl 语法兼容层；HTTP/2 保持实验状态，OSS/R2 云账号实网验收不属于本次发布范围。
+
+## 后续开发约定
+
+每次功能开发完成，同步更新这份功能索引、用法说明、`examples/` 和发布记录；删除或改变功能必须注明影响与迁移。代码、示例和文档一起回归后再发布。约定已记录在 [AGENTS.md](AGENTS.md)，后续开发继续遵循。
--- a/RELEASE.md
+++ b/RELEASE.md
@@ -1,4 +1,149 @@
-# v0.15.0-preview
+# v0.21.0-preview
+
+让带认证的 HTTP 调用和内部直连可以直接使用 httpc，减少手写 Transport 与 JSON 响应处理。
+
+- Proxy 支持环境、直连、固定代理；默认保留既有策略。
+- 建连、TCP keepalive、TLS 握手、响应头、100-continue、空闲超时和独立空闲连接数量可选配置；不修改全局 Transport，不关闭借用实例。
+- JSON 支持 WithHeader / WithHeaders / WithMaxResponseBytes；认证信息逐请求隔离，自动关闭和有界响应处理保留。
+- 成功路径减少请求复制和无用退避；output=nil 按限额流式丢弃；小错误体在大小和时间预算内尝试复用连接。
+- 不新增依赖、不增加业务规则；Do 保留标准流式扩展。CLI 最新版本与模板最低版本分开，本轮模板兼容门槛仍是 v0.20。
+
+```sh
+go get git.yuntuo.hk/k2safe/go-omni@v0.21.0-preview
+go install git.yuntuo.hk/k2safe/go-omni/cmd/go-omni@v0.21.0-preview
+```
+
+**兼容注意**：JSON 旧的直接调用仍有效，自定义 interface/函数值需要同步新增的 variadic 参数。自定义 Transport 与显式连接/代理/阶段参数混用现在报错，避免参数被忽略；迁移时在自己的 Transport 配置，或改用内置字段。没有删除原调用入口。
+
+[参数与使用说明](httpc/README.md)、[可运行示例](examples/httpClient/README.md)、[场景与性能验收](reports/httpcAcceptance.md) 已同步到 README。48 个测试包全量 race、Go 1.22 兼容、vet/build、约 110 万次请求头 fuzz 通过。性能来自本机同条件基准，不能代替项目实际流量验证；仍为 preview。
+
+---
+
+# v0.20.0-preview（历史版本）
+
+统一配置加载，减少生成项目重复维护的启动代码。
+
+- 生成器维护 `internal/config/loadGen.go`，调用 `config.LoadProject`；项目只扩展 Config/Default/Validate，可选在 loader.go/NewLoader 注册新格式。入口、环境覆盖、日志输出规范化无需业务重复实现。
+- JSON/YAML/XML 使用同一个加载与绑定流程；Decoder 通过实例注册，无全局 init 或额外强制依赖。内置格式、字段、文件大小与层数均有明确限制。
+- `config.Error` 携带文件、字段、环境变量、可用行列及安全原因；`Invalid` / `AtField` 支持业务验证。保留内部错误链，不自动输出原值；大整数、空集合、null、默认值隔离和自定义反序列化有回归覆盖。
+- 配置解析在日志、依赖和监听初始化之前；生成/check/dry-run 使用一致入口和文件所有权规则。
+- **迁移要求：旧项目先整理手写 Load，再重新生成。** 不静默覆盖业务文件。低层配置 API 保留；新项目不再复制手写加载流程。固定 Go 数组严格检查长度，YAML alias/merge/custom tag 不再接受，避免模糊覆盖和扩展行为。
+
+```sh
+go get git.yuntuo.hk/k2safe/go-omni@v0.20.0-preview
+go install git.yuntuo.hk/k2safe/go-omni/cmd/go-omni@v0.20.0-preview
+# 先按 CONFIG.md 迁移旧 Load，再执行：
+go-omni api generate
+go-omni api generate --check
+go test ./...
+go build .
+```
+
+完整用法、格式、脱敏边界和迁移见 [统一配置指南](CONFIG.md)，可运行例子见 [examples/configuration](examples/configuration/README.md)。回归、模糊测试与启动加载性能见 [验收记录](reports/configurationAcceptance.md)。47 个测试包的全量 race、Go 1.22 兼容、vet/build、30 秒 fuzz 与 5 个基准场景三轮测量通过。空缓存远程安装和 8 组生成消费者回归通过，无本地 replace；标签固定在 `c60841f901a3bcc3e9582eece6cfb2cad008fb9e`，见 [远程记录](reports/configurationRemote.json)。仍为 preview；项目的实际配置和业务依赖应自行验收。
+
+---
+
+# v0.19.0-preview（历史版本）
+
+将可选结构转换改为直接 Go 调用，减少业务项目需要维护的配置。普通接口继续使用 `.api` 生成 DTO，不要求增加独立模型或任何拷贝规则。
+
+- 新增只依赖标准库的 `copyx`：Copy、Clone、可复用 Copier；浅/深拷贝、严格字段覆盖、nil/零值策略、字段改名、忽略字段、精确类型 converter。没有全局注册和隐式数字强转。
+- 深拷贝检查整个输入和输出图。自定义 converter 原样返回指针、map、slice，或新对象仍嵌套旧引用时返回错误；保留普通循环图，拒绝资源对象及超出遍历/估算分配预算的输入。
+- 转换失败不提交部分目标；保留错误路径和原始错误链。并发复用只共享不可变类型元数据；源/目标读写和 converter 副作用由调用方负责。
+- **不兼容变更：删除 mappings / mappingFiles、Go 类型加载与映射代码生成。** 检出旧配置/旧生成文件时给出迁移提示；不会静默删除业务正在使用的代码。公共字段组合、scalar、中间件工厂、Repository 选项保留。
+- README 补齐当前能力入口、解释和用法，新增 [完整 copyx 指南](COPY.md)、[可运行示例](examples/copying)；[AGENTS.md](AGENTS.md) 记录每次修改同步文档/示例/移除说明的约定。
+
+```sh
+go get git.yuntuo.hk/k2safe/go-omni@v0.19.0-preview
+go install git.yuntuo.hk/k2safe/go-omni/cmd/go-omni@v0.19.0-preview
+# 如用过旧 mapping，先按 COPY.md 完成迁移：
+go-omni api generate
+go-omni api generate --check
+go test ./...
+```
+
+迁移步骤和语义边界见 [copyx](COPY.md#从旧-mapping-迁移)。新工具做运行时检查，不能声称具备旧生成器的编译期字段覆盖保证；实际类型对必须有测试。独立三端工资示例验证金额精度、缺失/null/零值、空集合、错误链和字段新增；不修改或代替接入项目的完整业务回归。
+
+46 个测试包的全量 race（含实际生成项目）、vet/build、Go 1.22 兼容测试通过；30 秒 fuzz 无失败，14 种基准场景各测量三轮。验收条件、性能数据及本轮未覆盖的外部环境见 [v0.19 验收记录](reports/copyxAcceptance.md)。本版仍为 preview。 空缓存远程 CLI 与 7 组真实生成消费者验收通过，无本地 replace；标签固定在 `fd83235ce7fc15ce88a482d385d70e61f25d7b32`，详见 [远程记录](reports/copyxRemote.json)。
+
+---
+
+以下是历史版本记录，其中 mapping 功能已在 v0.19 移除，不应继续作为当前接入方式。
+
+# v0.18.0-preview（历史版本）
+
+补齐可空嵌套映射和按模块拆分配置，减少重复转换代码，业务空值规则仍由项目显式选择：
+
+- 嵌套 mapping 支持 `*S → *T` 保留 nil、`S → *T`，以及指定 nil zero/error 后的 `*S → T`；同样适用于 slice/等长数组元素。错误保留字段路径、索引和内部错误链，失败不返回部分结果。
+- `mappingFiles` 显式引用项目内的映射文件，支持跨文件向前引用；统一检查重名、循环、类型与字段覆盖。禁止多层导入、路径越界和隐式覆盖，生成期间核对全部配置输入。
+- 同类型 `*T → T` 可显式配置 nil zero/error；现有 converter 保持完整控制，不默认放宽类型或混入领域规则。
+- `pointerResult: true` 额外生成 `<Name>Ptr(S) (*T,error)`，原值函数保留；失败返回 nil 与原错误，辅助函数名冲突在生成前拒绝。
+
+```sh
+go get git.yuntuo.hk/k2safe/go-omni@v0.18.0-preview
+go install git.yuntuo.hk/k2safe/go-omni/cmd/go-omni@v0.18.0-preview
+go-omni api generate
+go-omni api generate --check
+go test ./...
+```
+
+v0.17 的单文件 mappings、现有 converter 和业务文件继续保留。配置拆分时移动完整映射条目，主配置显式列出子文件；不保留重复定义。新能力均为可选生成配置，不增加运行时依赖。nil zero 表示 Go 零值并跳过子映射；业务必填、金额精度、编号格式和快照复制仍由项目负责。
+
+使用与迁移见 [生成能力指南](GENERATION.md)，回归和发布后验收见 [验收记录](reports/nullableMappingAcceptance.md)。本版仍为 preview。
+
+全量 44 个测试包的 race、vet、build 和实际进程验收通过；空缓存远程 CLI 与 8 组实际生成消费者回归也通过，同版依赖且无本地 replace。标签固定在 `4563a6354fac19f22cd8d407fd76d98b8cc9c406`。
+
+---
+
+# v0.17.0-preview（历史版本）
+
+减少项目里的重复声明、字段赋值和中间件装配代码，业务规则继续由项目控制：
+
+- `.api` 公共字段组合：保持 JSON 平铺，DTO、绑定、校验和 OpenAPI 同步；字段冲突、循环和超限明确报错。
+- 可选结构映射：在 `omni.gen.json` 显式声明源与目标，生成编译期检查的普通 Go 赋值。不同字段名、金额、时间和指针转换由项目指定函数；遗漏字段与类型错误在写文件前失败。不使用 JSON 往返或运行时反射。
+- 带依赖的中间件工厂：svc 初始化依赖后自动调用 `New<Name>(deps)` 并注册；错误、nil 或 panic 阻止启动，已登记资源按生命周期清理。
+- Repository 骨架默认关闭，可按 group 启用；已有业务文件始终保留。生成选项与映射纳入重新生成和 `--check`。
+
+```sh
+go get git.yuntuo.hk/k2safe/go-omni@v0.17.0-preview
+go install git.yuntuo.hk/k2safe/go-omni/cmd/go-omni@v0.17.0-preview
+go-omni api generate
+go-omni api generate --check
+go test ./...
+```
+
+新项目默认使用 factories；已有项目首次升级保留 handlers 模式，需要显式迁移后再切换。映射按需开启，先准备业务类型、转换函数和依赖，再声明映射；普通引用赋值保留 Go 语义，缺失/null 语义由项目类型与转换函数定义。
+
+使用方法、文件归属和升级步骤见 [生成能力指南](GENERATION.md)，回归与发布验收见 [验收记录](reports/generationExperienceAcceptance.md)。本版仍为 preview；框架验收不等于业务项目完成迁移。
+
+全量 44 个测试包的 race、vet、build 和实际进程验收通过；发布后的空缓存远程 CLI 与 7 组生成消费者回归也通过，同版依赖且无本地 replace。标签固定在 `8b588a24cd653dac77dd68f6777e0db367981f19`。
+
+---
+
+# v0.16.0-preview（历史版本）
+
+补齐通用契约与生成体验，业务响应协议继续由项目定义：
+
+- `returns([]string/[]int64/[]bool/[]any)` 及其他支持的基础类型数组，贯通 Logic、Handler、OpenAPI 和生成检查。nil 根数组输出 `[]`；DTO 数组、nullable、null、raw 和 204 保持原语义。字节数组明确拒绝 base64/数组歧义。
+- OpenAPI 以标准 components / `$ref` 共享重复响应、schema、示例；保留同一 HTTP 200 下的成功与失败、模板参数、数字业务码和 data:null。
+- workspace 显式配置 Go Catalog 提供方，一次导出共享 JSON，多服务通过受控根引用。支持服务/路由的文档错误列表，运行期 App 目录继承不变。check 核对导出漂移并保持项目文件不变。
+- EnvOptions.Aliases + ServerEnvAliases 统一完整配置与框架短名称的 Lookup、类型转换、空值规则。完整名称优先，显式空值不等于未设置；旧 ApplyEnv 的空值/逗号列表行为保留。
+
+```sh
+go get git.yuntuo.hk/k2safe/go-omni@v0.16.0-preview
+go install git.yuntuo.hk/k2safe/go-omni/cmd/go-omni@v0.16.0-preview
+go-omni api generate
+go-omni api generate --check
+go test ./...
+```
+
+旧项目 config/Logic/svc 继续由开发者维护，不会被重新生成覆盖。已有环境配置需按 [一次覆盖完整配置](DEVELOPMENT.md#一次覆盖完整配置与-http日志短名称) 合并 OverlayEnv 与 ApplyEnv；共享错误目录接入见 [workspace 配置](DEVELOPMENT.md#同一份-go-错误目录供多个服务生成)。已有手写权限 Handler 切换自动生成前，先迁出实现并显式移除 Manual 文件，生成器不会静默删除。
+
+全量 race（含实际生成消费者）、vet、build、根入口/退出/再生成验证通过。eTax 只读契约验收：API 文档 20,751,149 → 847,171 字节，ID 文档 1,008,210 → 392,481 字节；70 个操作展开引用后与原文档完全一致。空缓存远程 CLI / 固定版本消费者验收也已通过，没有本地 replace；标签固定在 `64e3bd6cfced225476d58e95037249cd0a4fe695`。详见 [验收记录](reports/contractFollowupAcceptance.md)。这不代表已完成业务项目迁移。
+
+---
+
+# v0.15.0-preview（历史版本）

 增加通用后台分阶段关闭：生成入口先完成 HTTP 排空，再运行全部 OnStop、全部 OnDrain，确认组件收尾后逆序释放 OnClose 资源，最后关闭日志。适用于任意后台组件；不引入 Orbit，不改变业务事务或任务一致性策略。

@@ -18,7 +163,7 @@ go test ./...

 v0.14.x 无需重写 svc/config；生成器更新 main/runtimeGen，未配置时使用默认时限。也可 api upgrade --dry-run/--apply 更新依赖与生成文件，保留已有项目扩展。需要阶段保证的旧后台 OnClose 登记，应显式迁到 Stop/Drain；v0.13 及更早版本仍按原迁移指南处理。

-全量 race（含实际生成项目）、vet、build 和隔离 MySQL/GORM 验收已通过。详见 [生命周期接入](lifecycle/README.md#后台组件分阶段关闭) 与 [验收记录](reports/phasedLifecycleAcceptance.md)。Go 无法强制结束任意 goroutine；OnClose 仍须能返回，HTTP 处理器仍须响应取消。此版不会将未知的第三方组件自动改造成优雅关闭组件。
+全量 race（含实际生成项目）、vet、build 和隔离 MySQL/GORM 验收已通过。发布后的空缓存远程生成项目与真实 MySQL/GORM 验收也通过，CLI/框架同版且无本地 replace；标签固定在 `16deead70e860052c5b629511207578c03f9b2cb`。详见 [生命周期接入](lifecycle/README.md#后台组件分阶段关闭) 与 [验收记录](reports/phasedLifecycleAcceptance.md)。Go 无法强制结束任意 goroutine；OnClose 仍须能返回，HTTP 处理器仍须响应取消。此版不会将未知的第三方组件自动改造成优雅关闭组件。

 ---

--- a/ROADMAP.md
+++ b/ROADMAP.md
@@ -1,5 +1,8 @@
 # GoOmni 成熟度计划

+当前发布基线为 v0.19.0-preview：普通接口通过 `.api` → DTO → Logic 开发；独立类型需要转换时可选 copyx。旧 JSON mapping 生成已移除，见 [迁移说明](COPY.md)。当前能力、使用入口和限制以 [README](README.md) 与 [发布记录](RELEASE.md) 为准。下文保留阶段性建设记录。
+
+
 当前进展：`v0.14.0-preview` 已完成契约驱动的业务开发能力、通用 Runtime/配置和官方 MySQL 适配器，并通过全量 race、实际生成服务及空缓存远程验收。新项目/升级以 [README](README.md) 和 [开发指南](DEVELOPMENT.md) 为准；下方为历史阶段记录，完整本轮验收见 [报告](reports/businessDevelopmentAcceptance.md)。具体 eTax/ePay 业务迁移与业务回归仍由接入项目完成。

 ## 1. 新项目启动与发布流程（已完成，v0.1.1）
--- a/cmd/go-omni/README.md
+++ b/cmd/go-omni/README.md
@@ -1,5 +1,11 @@
 # go-omni CLI

+v0.19 移除结构映射生成：`omni.gen.json` 只保留 Repository 和中间件选项。普通接口直接使用生成 DTO；需要类型转换时用普通 Go 或可选 [copyx](../../COPY.md)。旧 `mappings` / `mappingFiles` 必须按迁移步骤清理，CLI 不会静默删除仍在调用的旧生成文件。
+
+公共字段组合、中间件工厂和按需 Repository 继续支持，见 [生成能力指南](../../GENERATION.md)。
+
+v0.16 增加基础类型/动态 JSON 数组返回、OpenAPI 公共引用和 workspace Go Catalog 统一导出。见 [接入与筛选规则](../../DEVELOPMENT.md#同一份-go-错误目录供多个服务生成)。
+
 v0.14 新增 `api format [--check]`、`api upgrade [--dry-run|--preview <空目录>|--apply]`，以及 `workspace format|generate|check --file omni.workspace.json`。详见 [通用开发指南](../../DEVELOPMENT.md)。

 新项目采用根目录 `main.go` 与 `internal/config、svc、logic、handler、types`。完整职责、启动扩展、流式接口和生成文件边界见 [项目指南](../../PROJECT.md)。
@@ -8,14 +14,14 @@ v0.14 新增 `api format [--check]`、`api upgrade [--dry-run|--preview <空目

 ```sh
 # 仓库读取权限与 PATH 配置见根目录 README
-go install git.yuntuo.hk/k2safe/go-omni/cmd/go-omni@v0.15.0-preview
+go install git.yuntuo.hk/k2safe/go-omni/cmd/go-omni@v0.21.0-preview
 go-omni new --module example.com/hello ./hello

 # 从自己的契约生成；service.api 及其相对 import 文件需要在本地存在
 go-omni new --api service.api --module example.com/example ./example
 ```

-`new` 与 `api new` 统一生成契约项目；不再提供另一套 CRUD 启动目录。未实现的 Logic / 中间件骨架返回 501。进入项目执行 `go mod tidy`、`go run .`、`go build .`。
+`new` 与 `api new` 统一生成契约项目；不再提供另一套 CRUD 启动目录。未实现的 Logic 返回 501；中间件工厂未实现时阻止启动，既有 handler 模式仍返回 501。进入项目执行 `go mod tidy`、`go run .`、`go build .`。

 参数：`--database none|memory|mysql`（默认 none；memory 等同 none），`--storage none|local|s3|r2|oss`，`--log-output stdout|stderr|file`，`--log-format json|text`。基础设施按需生成，连接凭据由环境提供，不自动创建数据库、表或云资源。选择 MySQL 不会凭空生成业务表或 Repository 查询。

@@ -43,14 +49,14 @@ main、Gen.go、OpenAPI 和 manifest 由生成器维护；业务文件按字节

 ## 版本与迁移

-CLI 与框架依赖固定使用 v0.15.0-preview。远程安装的 CLI 默认把自身版本写入 go.mod，不添加本地 replace；`--framework-version` 可显式指定已发布的兼容版本。仅在开发框架源码时使用本地替换：
+CLI 与框架依赖固定使用 v0.20.0-preview。远程安装的 CLI 默认把自身版本写入 go.mod，不添加本地 replace；`--framework-version` 可显式指定已发布的兼容版本。仅在开发框架源码时使用本地替换：

 ```sh
 # 在 go-omni 源码仓库中执行
 go run ./cmd/go-omni new --module example.com/hello --framework-dir . ../hello
 ```

-模板最低需要 v0.15.0-preview 的分阶段 Runtime 能力，继续使用 manifest v2；GORM 可选适配器从 v0.14.1-preview 提供。已有项目使用 [定点升级与预览](../../DEVELOPMENT.md#v013-项目升级)：原始模板可自动替换，含业务修改的基础文件按预览合并；通用清理由 Runtime 负责。独立工具命令不会被删除。受管理项目通过 `.api` 模块导入增加业务，不使用旧 `add` 命令的手动路由装配。
+当前模板与依赖以 v0.20.0-preview 为基线，继续使用 manifest v2；GORM 可选适配器从 v0.14.1-preview 提供。已有项目使用 [定点升级与预览](../../DEVELOPMENT.md#v013-项目升级)：原始模板可自动替换，含业务修改的基础文件按预览合并；通用清理由 Runtime 负责。独立工具命令不会被删除。受管理项目通过 `.api` 模块导入增加业务，不使用旧 `add` 命令的手动路由装配。

 ## 数据库迁移命令

@@ -63,3 +69,7 @@ go-omni migrate --dir migrations --apply
 ```

 SQL 命名示例 `0001_createUsers.up.sql`；预览只显示版本和 SHA-256，不连接数据库。失败保留 dirty 状态，不自动 down/force。细节见 [扩展模块](../../ADVANCED.md)。
+
+### v0.20 配置入口
+
+新生成 `internal/config/loadGen.go` 调用统一加载，纳入生成检查；项目 config.go 只维护字段、默认值和校验，loader.go 用于注册额外格式。JSON/YAML/XML 内置。旧手写 Load 会阻止生成，请先按 [迁移步骤](../../CONFIG.md#v019-及更早项目迁移) 整理，不会自动覆盖业务代码。
--- a/cmd/go-omni/apigen/apigen_test.go
+++ b/cmd/go-omni/apigen/apigen_test.go
@@ -170,6 +170,7 @@ func TestRegenerationAndConflicts(t *testing.T) {
 	servicePath := filepath.Join(dir, "internal/logic/greet/greet.go")
 	service := readFile(t, servicePath) + "\n// user edit must survive\n"
 	writeFile(t, servicePath, service)
+	writeFile(t, filepath.Join(dir, "internal/repository/greet/repository.go"), "package greet\n")
 	for _, file := range []string{"etc/config.yaml", "internal/svc/serviceContext.go", "internal/repository/greet/repository.go"} {
 		body := readFile(t, filepath.Join(dir, file))
 		if strings.HasSuffix(file, ".go") {
@@ -301,6 +302,7 @@ func TestGeneratedProjectsBuildAndRun(t *testing.T) {
 			if starter {
 				_, err = New(o)
 			} else {
+				writeFile(t, filepath.Join(dir, generatorConfigFile), `{"middleware":"handlers"}`)
 				o.API = filepath.Join(root, "examples/contracts/user.api")
 				_, err = Generate(o)
 			}
--- a/cmd/go-omni/apigen/arrayResponse_test.go
+++ b/cmd/go-omni/apigen/arrayResponse_test.go
@@ -0,0 +1,104 @@
+package apigen
+
+import (
+	"context"
+	"encoding/json"
+	"fmt"
+	"os"
+	"os/exec"
+	"path/filepath"
+	"strings"
+	"testing"
+	"time"
+)
+
+func TestPrimitiveArrayContracts(t *testing.T) {
+	for _, name := range []string{"string", "bool", "int", "int8", "int16", "int32", "int64", "uint", "uint16", "uint32", "uint64", "float32", "float64", "any"} {
+		t.Run(name, func(t *testing.T) {
+			spec, err := parseText(t, fmt.Sprintf("service arrays{\n@handler list\nget /list returns ([]%s)\n}", name))
+			if err != nil {
+				t.Fatal(err)
+			}
+			c, err := Compile(spec)
+			if err != nil {
+				t.Fatal(err)
+			}
+			schema := operation(t, document(t, c), "/list", "get")["responses"].(map[string]any)["200"].(map[string]any)["content"].(map[string]any)["application/json"].(map[string]any)["schema"].(map[string]any)
+			data := schema["properties"].(map[string]any)["data"].(map[string]any)
+			if data["type"] != "array" || data["items"] == nil {
+				t.Fatal(data)
+			}
+			if name == "any" && len(data["items"].(map[string]any)) != 0 {
+				t.Fatal("dynamic JSON was constrained")
+			}
+			if responseGoType("[]"+name) != "[]"+name || responseNeedsTypes("[]"+name) {
+				t.Fatal("wrong Go signature/import")
+			}
+		})
+	}
+	for _, name := range []string{"uint8", "File", "Unknown", "[]string"} {
+		spec, err := parseText(t, fmt.Sprintf("service arrays{\n@handler list\nget /list returns ([]%s)\n}", name))
+		if err == nil {
+			_, err = Compile(spec)
+		}
+		if err == nil {
+			t.Fatal("unsupported root accepted", name)
+		}
+	}
+}
+
+func TestPrimitiveArrayConsumer(t *testing.T) {
+	if os.Getenv("GO_OMNI_SCAFFOLD_INTEGRATION") != "1" {
+		t.Skip("set GO_OMNI_SCAFFOLD_INTEGRATION=1")
+	}
+	dir := filepath.Join(t.TempDir(), "arrays")
+	o := Options{Dir: dir, API: filepath.Join(frameworkRoot(t), "examples/contracts/arrays.api"), Module: "example.com/arrays", FrameworkDir: frameworkRoot(t)}
+	if err := generateManagedTestProject(t, o); err != nil {
+		t.Fatal(err)
+	}
+	for _, name := range []string{"strings", "integers", "dynamic", "empty", "raw"} {
+		writeFile(t, filepath.Join(dir, "internal/logic/arrays/"+name+".go"), "package arrays\n")
+	}
+	writeFile(t, filepath.Join(dir, "internal/logic/arrays/values.go"), readFile(t, "testdata/arrays/values.go"))
+	writeFile(t, filepath.Join(dir, "consumer_test.go"), readFile(t, "testdata/arrays/consumer_test.go"))
+	o.API = filepath.Join(dir, "api/arrays.api")
+	if err := generateManagedTestProject(t, o); err != nil {
+		t.Fatal(err)
+	}
+	if !strings.Contains(readFile(t, filepath.Join(dir, "internal/logic/arrays/values.go")), "企业") {
+		t.Fatal("logic overwritten")
+	}
+	o.Check = true
+	if err := generateManagedTestProject(t, o); err != nil {
+		t.Fatal(err)
+	}
+	ctx, cancel := context.WithTimeout(context.Background(), 90*time.Second)
+	defer cancel()
+	cmd := exec.CommandContext(ctx, "go", "test", "-race", "-mod=mod", "-count=1", "./...")
+	cmd.Dir = dir
+	cmd.Env = append(os.Environ(), "GOWORK=off")
+	if out, err := cmd.CombinedOutput(); err != nil {
+		t.Fatalf("%v\n%s", err, out)
+	}
+	if os.Getenv("GO_OMNI_RELEASE_CLI") != "" {
+		cmd = exec.CommandContext(ctx, "go", "list", "-m", "-json", frameworkModule)
+		cmd.Dir = dir
+		cmd.Env = append(os.Environ(), "GOWORK=off")
+		raw, err := cmd.CombinedOutput()
+		if err != nil {
+			t.Fatal(err, string(raw))
+		}
+		var module struct {
+			Version, Sum string
+			Replace      any
+		}
+		if err = json.Unmarshal(raw, &module); err != nil {
+			t.Fatal(err)
+		}
+		if module.Version != os.Getenv("GO_OMNI_RELEASE_VERSION") || module.Replace != nil || module.Sum == "" {
+			t.Fatal("not a fixed remote consumer")
+		}
+		t.Logf("remote framework %s checksum %s; no local replace", module.Version, module.Sum)
+	}
+
+}
--- a/cmd/go-omni/apigen/business_test.go
+++ b/cmd/go-omni/apigen/business_test.go
@@ -40,6 +40,7 @@ func TestBusinessGeneratedProject(t *testing.T) {
 		t.Skip("set GO_OMNI_SCAFFOLD_INTEGRATION=1")
 	}
 	dir := filepath.Join(t.TempDir(), "business")
+	writeFile(t, filepath.Join(dir, generatorConfigFile), `{"middleware":"handlers"}`)
 	o := Options{Dir: dir, API: filepath.Join(frameworkRoot(t), "examples/contracts/business.api"), Module: "example.com/business", FrameworkDir: frameworkRoot(t)}
 	if err := generateManagedTestProject(t, o); err != nil {
 		t.Fatal(err)
--- a/cmd/go-omni/apigen/catalogDocument.go
+++ b/cmd/go-omni/apigen/catalogDocument.go
@@ -2,41 +2,73 @@ package apigen

 import (
 	"errors"
+	"fmt"
 	apierrors "git.yuntuo.hk/k2safe/go-omni/errors"
 	"git.yuntuo.hk/k2safe/go-omni/response"
 	"io"
 	"os"
 	"path/filepath"
+	"strings"
 )

 const catalogDocumentFile = "omni.errors.json"

-func readDocumentCatalog(root string, spec *Spec) error {
-	path := filepath.Join(root, catalogDocumentFile)
-	stat, err := os.Lstat(path)
-	if errors.Is(err, os.ErrNotExist) {
-		return nil
+// DocumentErrors selects documentation only. Runtime App inheritance and
+// route-local @errors declarations are never changed by this metadata.
+// A nil Include lists all errors; [] lists none. Routes override Include.
+type DocumentErrors struct {
+	Source  string              `json:"source"`
+	Include []string            `json:"include"`
+	Routes  map[string][]string `json:"routes,omitempty"`
+}
+
+func readDocumentCatalog(root string, spec *Spec, overrides map[string][]byte) error {
+	name := catalogDocumentFile
+	path := filepath.Join(root, name)
+	// Shared metadata uses the same explicitly authorized roots as .api imports.
+
+	if selection := spec.DocumentErrors; selection != nil {
+		if _, err := os.Lstat(path); !errors.Is(err, os.ErrNotExist) {
+			return errors.New("api: use either local omni.errors.json or shared errors.source, not both")
+		}
+		name = selection.Source
+		alias, sub, ok := strings.Cut(strings.TrimPrefix(name, "@"), "/")
+		declared, found := spec.SharedRoots[alias]
+		if !strings.HasPrefix(name, "@") || !ok || !found || sub == "" || filepath.Ext(sub) != ".json" {
+			return errors.New("api: errors.source must name a JSON file in a declared @root")
+		}
+		if err := safePath(declared.Path, sub); err != nil {
+			return err
+		}
+		path = filepath.Join(declared.Path, filepath.FromSlash(sub))
 	}
-	if err != nil {
-		return err
-	}
-	if !stat.Mode().IsRegular() {
-		return errors.New("api: error metadata must be a regular file")
-	}
-	file, err := os.Open(path)
-	if err != nil {
-		return err
-	}
-	defer file.Close()
-	raw, err := io.ReadAll(io.LimitReader(file, (1<<20)+1))
-	if err != nil {
-		return err
+	raw, ok := overrides[path]
+	if !ok {
+		stat, err := os.Lstat(path)
+		if errors.Is(err, os.ErrNotExist) && spec.DocumentErrors == nil {
+			return nil
+		}
+		if err != nil {
+			return err
+		}
+		if !stat.Mode().IsRegular() {
+			return errors.New("api: error metadata must be a regular file")
+		}
+		f, err := os.Open(path)
+		if err != nil {
+			return err
+		}
+		defer f.Close()
+		raw, err = io.ReadAll(io.LimitReader(f, (1<<20)+1))
+		if err != nil {
+			return err
+		}
 	}
 	if len(raw) > 1<<20 {
 		return errors.New("api: error metadata exceeds 1 MiB")
 	}
 	var catalog apierrors.Catalog
-	if err = apierrors.DecodeCatalogJSON(raw, &catalog); err != nil {
+	if err := apierrors.DecodeCatalogJSON(raw, &catalog); err != nil {
 		return err
 	}
 	registry, err := apierrors.NewRegistry(catalog)
@@ -45,10 +77,70 @@ func readDocumentCatalog(root string, spec *Spec) error {
 	}
 	normalized := registry.Catalog()
 	spec.DocumentCatalog = &normalized
-	spec.Sources[catalogDocumentFile] = raw
-	spec.SourcePaths[catalogDocumentFile] = path
+	spec.Sources[name] = raw
+	spec.SourcePaths[name] = path
+	return validateDocumentSelection(spec)
+}
+
+func documentRouteCatalog(spec *Spec, route Route) apierrors.Catalog {
+	catalog := spec.DocumentCatalog.Clone()
+	if spec.DocumentErrors == nil {
+		return catalog
+	}
+	include := spec.DocumentErrors.Include
+	if selected, ok := spec.DocumentErrors.Routes[strings.ToUpper(route.Method)+" "+route.Path]; ok {
+		include = selected
+	}
+	if include != nil {
+		selected := map[string]apierrors.Definition{}
+		for _, key := range include {
+			selected[key] = catalog.Definitions[key]
+		}
+		catalog.Definitions = selected
+	}
+	return catalog
+}
+
+func validateDocumentSelection(spec *Spec) error {
+	cfg := spec.DocumentErrors
+	if cfg == nil {
+		return nil
+	}
+	validate := func(keys []string) error {
+		seen := map[string]bool{}
+		for _, key := range keys {
+			if _, ok := spec.DocumentCatalog.Definitions[key]; !ok {
+				return fmt.Errorf("api: unknown documentation error %q", key)
+			}
+			if seen[key] {
+				return fmt.Errorf("api: duplicate documentation error %q", key)
+			}
+			seen[key] = true
+		}
+		return nil
+	}
+	if err := validate(cfg.Include); err != nil {
+		return err
+	}
+	routes := map[string]Route{}
+	for _, r := range spec.Routes {
+		routes[strings.ToUpper(r.Method)+" "+r.Path] = r
+	}
+	for key, keys := range cfg.Routes {
+		r, ok := routes[key]
+		if !ok {
+			return fmt.Errorf("api: unknown documentation route %q", key)
+		}
+		if len(r.Errors) > 0 {
+			return fmt.Errorf("api: %s already declares route-local errors", key)
+		}
+		if err := validate(keys); err != nil {
+			return err
+		}
+	}
 	return nil
 }
+
 func validateDocumentCatalog(spec *Spec) error {
 	if spec.DocumentCatalog == nil {
 		return nil
@@ -61,7 +153,7 @@ func validateDocumentCatalog(spec *Spec) error {
 		if err != nil {
 			return err
 		}
-		if err = policy.ValidateErrors(*spec.DocumentCatalog); err != nil {
+		if err = policy.ValidateErrors(documentRouteCatalog(spec, r)); err != nil {
 			return err
 		}
 	}
--- a/cmd/go-omni/apigen/compile.go
+++ b/cmd/go-omni/apigen/compile.go
@@ -40,6 +40,9 @@ func Compile(spec *Spec) (*Compiled, error) {
 	if prepareErr != nil {
 		return nil, prepareErr
 	}
+	if err := expandFields(spec); err != nil {
+		return nil, err
+	}
 	if err := validateDocumentCatalog(spec); err != nil {
 		return nil, err
 	}
@@ -70,7 +73,7 @@ func Compile(spec *Spec) (*Compiled, error) {
 	resolving := map[string]bool{}
 	var resolve func(string, int) (reflect.Type, error)
 	var expression func(ast.Expr, int) (reflect.Type, error)
-	primitives := map[string]reflect.Type{"File": reflect.TypeOf(contract.File{}), "any": reflect.TypeOf((*any)(nil)).Elem(), "string": reflect.TypeOf(""), "bool": reflect.TypeOf(false), "int": reflect.TypeOf(int(0)), "int8": reflect.TypeOf(int8(0)), "int16": reflect.TypeOf(int16(0)), "int32": reflect.TypeOf(int32(0)), "int64": reflect.TypeOf(int64(0)), "uint": reflect.TypeOf(uint(0)), "uint8": reflect.TypeOf(uint8(0)), "uint16": reflect.TypeOf(uint16(0)), "uint32": reflect.TypeOf(uint32(0)), "uint64": reflect.TypeOf(uint64(0)), "float32": reflect.TypeOf(float32(0)), "float64": reflect.TypeOf(float64(0))}
+
 	expression = func(e ast.Expr, depth int) (reflect.Type, error) {
 		if depth > 32 {
 			return nil, errors.New("type nesting exceeds 32")
@@ -80,7 +83,7 @@ func Compile(spec *Spec) (*Compiled, error) {
 			if t, ok := scalarTypes[e.Name]; ok {
 				return t, nil
 			}
-			if t, ok := primitives[e.Name]; ok {
+			if t, ok := primitiveTypes[e.Name]; ok {
 				return t, nil
 			}
 			return resolve(e.Name, depth+1)
@@ -313,6 +316,7 @@ func Compile(spec *Spec) (*Compiled, error) {
 		return nil, err
 	}
 	decorateDocument(doc, spec, c.Bindings)
+	compactDocument(doc)
 	c.Document, err = json.MarshalIndent(doc, "", "  ")
 	return c, err
 }
--- a/cmd/go-omni/apigen/composition.go
+++ b/cmd/go-omni/apigen/composition.go
@@ -0,0 +1,102 @@
+package apigen
+
+import (
+	"fmt"
+	"reflect"
+	"strings"
+)
+
+// expandFields copies definitions rather than embedding Go structs. Binding,
+// validation, DTOs, snapshots and OpenAPI all consume the same flattened fields.
+func expandFields(spec *Spec) error {
+	definitions := map[string]Type{}
+	for _, t := range spec.Types {
+		if _, exists := definitions[t.Name]; exists {
+			return fmt.Errorf("%s: duplicate type %s", t.Position, t.Name)
+		}
+		definitions[t.Name] = t
+	}
+	expanded := map[string]Type{}
+	heights := map[string]int{}
+	visiting := map[string]bool{}
+	total := 0
+	var expand func(string, int) (Type, error)
+	expand = func(name string, depth int) (Type, error) {
+		if t, ok := expanded[name]; ok {
+			if depth+heights[name] > 32 {
+				return Type{}, fmt.Errorf("field composition exceeds 32 levels at %s", name)
+			}
+			return t, nil
+		}
+		if visiting[name] {
+			return Type{}, fmt.Errorf("field composition cycle at %s", name)
+		}
+		if depth > 32 {
+			return Type{}, fmt.Errorf("field composition exceeds 32 levels at %s", name)
+		}
+		t, ok := definitions[name]
+		if !ok {
+			return Type{}, fmt.Errorf("unknown composed object type %s", name)
+		}
+		visiting[name] = true
+		defer delete(visiting, name)
+		fields := []Field{}
+		height := 0
+		seen, wire := map[string]bool{}, map[string]bool{}
+		for _, f := range t.Fields {
+			add := []Field{f}
+			if f.Type == "" {
+				child, err := expand(f.Name, depth+1)
+				if err != nil {
+					return Type{}, fmt.Errorf("%s.%s: %w", name, f.Name, err)
+				}
+				add = child.Fields
+				if heights[f.Name]+1 > height {
+					height = heights[f.Name] + 1
+				}
+				if height > 32 {
+					return Type{}, fmt.Errorf("field composition exceeds 32 levels at %s", name)
+				}
+			}
+			for _, field := range add {
+				if seen[field.Name] {
+					return Type{}, fmt.Errorf("%s: conflicting composed field %s", name, field.Name)
+				}
+				seen[field.Name] = true
+				for _, source := range []string{"json", "form", "path", "header", "multipart", "multipartJSON", "file"} {
+					tag := strings.Split(reflect.StructTag(field.Tag).Get(source), ",")[0]
+					if tag == "" || tag == "-" {
+						continue
+					}
+					if source == "header" {
+						tag = strings.ToLower(tag)
+					}
+					key := source + ":" + tag
+					if wire[key] {
+						return Type{}, fmt.Errorf("%s: conflicting composed field tag %s", name, key)
+					}
+					wire[key] = true
+				}
+				fields = append(fields, field)
+				total++
+				if len(fields) > 4096 || total > 65536 {
+					return Type{}, fmt.Errorf("field composition expansion limit exceeded")
+				}
+			}
+		}
+		t.Fields = fields
+		expanded[name] = t
+		heights[name] = height
+		return t, nil
+	}
+	result := make([]Type, 0, len(spec.Types))
+	for _, t := range spec.Types {
+		out, err := expand(t.Name, 0)
+		if err != nil {
+			return err
+		}
+		result = append(result, out)
+	}
+	spec.Types = result
+	return nil
+}
--- a/cmd/go-omni/apigen/composition_test.go
+++ b/cmd/go-omni/apigen/composition_test.go
@@ -0,0 +1,163 @@
+package apigen
+
+import (
+	"bytes"
+	"encoding/json"
+	"fmt"
+	"os"
+	"path/filepath"
+	"strings"
+	"testing"
+)
+
+func TestFieldComposition(t *testing.T) {
+	source := readFile(t, "testdata/composition/service.api")
+	spec, err := parseText(t, source)
+	if err != nil {
+		t.Fatal(err)
+	}
+	first, err := Compile(spec)
+	if err != nil {
+		t.Fatal(err)
+	}
+	second, err := Compile(spec)
+	if err != nil {
+		t.Fatal(err)
+	}
+	if !bytes.Equal(first.Document, second.Document) || len(spec.Types[1].Fields) != 1 {
+		t.Fatal("composition mutates input")
+	}
+	for _, name := range []string{"EnterpriseRequest", "TenantRequest", "AdminRequest"} {
+		schema := first.Bindings[name].BodySchema()
+		raw, _ := json.Marshal(schema)
+		if !bytes.Contains(raw, []byte("Employee display name.")) || bytes.Contains(raw, []byte("SalaryFields")) {
+			t.Fatalf("flattened schema/comment missing: %s", raw)
+		}
+	}
+	cases := []struct{ name, decl, want string }{
+		{"unknown", "type Req {\n Missing\n}", "unknown composed"},
+		{"cycle", "type Req {\n Other\n}\ntype Other {\n Req\n}", "cycle"},
+		{"conflict", "type Base {\n Name string `json:\"name\"`\n}\ntype Req {\n Base\n Name string `json:\"other\"`\n}", "conflicting"},
+		{"wireConflict", "type Base {\n Name string `json:\"name\"`\n}\ntype Req {\n Base\n Other string `json:\"name\"`\n}", "conflicting"},
+		{"tagged", "type Req {\n Other `json:\"other\"`\n}", "cannot carry"},
+		{"diamond", "type Base {\n Name string `json:\"name\"`\n}\ntype Left {\n Base\n}\ntype Right {\n Base\n}\ntype Req {\n Left\n Right\n}", "conflicting"},
+	}
+	for _, tc := range cases {
+		t.Run(tc.name, func(t *testing.T) {
+			s, e := parseText(t, tc.decl+"\nservice demo{\n@handler post\npost / (Req)\n}")
+			if e == nil {
+				_, e = Compile(s)
+			}
+			if e == nil || !strings.Contains(e.Error(), tc.want) {
+				t.Fatal(e)
+			}
+		})
+	}
+	// Imports can contain reusable definitions and retain the existing root policy.
+	dir := t.TempDir()
+	writeFile(t, filepath.Join(dir, "base.api"), "type Base {\n Name string `json:\"name\"`\n}\n")
+	writeFile(t, filepath.Join(dir, "service.api"), "import \"base.api\"\ntype Req {\n Base\n}\nservice demo{\n@handler post\npost / (Req)\n}")
+	if _, err := FormatProject(filepath.Join(dir, "service.api"), false); err != nil {
+		t.Fatal(err)
+	}
+	if _, err := FormatProject(filepath.Join(dir, "service.api"), true); err != nil {
+		t.Fatal(err)
+	}
+}
+
+func TestRepositoryGenerationOptions(t *testing.T) {
+	dir := filepath.Join(t.TempDir(), "app")
+	if _, err := New(Options{Dir: dir, Module: "example.com/repository", FrameworkDir: frameworkRoot(t)}); err != nil {
+		t.Fatal(err)
+	}
+	if _, err := os.Stat(filepath.Join(dir, "internal/repository")); !os.IsNotExist(err) {
+		t.Fatal("default creates repository")
+	}
+	o := Options{Dir: dir, API: filepath.Join(dir, "api/service.api")}
+	writeFile(t, filepath.Join(dir, generatorConfigFile), `{"repository":"group","middleware":"factories"}`)
+	if _, err := Generate(o); err != nil {
+		t.Fatal(err)
+	}
+	repo := filepath.Join(dir, "internal/repository/greet/repository.go")
+	original := readFile(t, repo) + "\n// business SQL belongs here\n"
+	writeFile(t, repo, original)
+	writeFile(t, filepath.Join(dir, generatorConfigFile), `{"repository":"none","middleware":"factories"}`)
+	if _, err := Generate(o); err != nil {
+		t.Fatal(err)
+	}
+	o.Check = true
+	if _, err := Generate(o); err != nil {
+		t.Fatal(err)
+	}
+	if readFile(t, repo) != original {
+		t.Fatal("repository removed or overwritten")
+	}
+	for _, raw := range []string{`{"repository":"oops"}`, `{"middleware":"oops"}`, `{"unknown":true}`, `{"repository":"none","repository":"group"}`} {
+		writeFile(t, filepath.Join(dir, generatorConfigFile), raw)
+		before := snapshot(t, dir)
+		if _, err := Generate(o); err == nil {
+			t.Fatal("accepted", raw)
+		}
+		if !sameFiles(before, snapshot(t, dir)) {
+			t.Fatal("invalid config wrote files")
+		}
+	}
+}
+
+func TestCompositionExpansionBound(t *testing.T) {
+	var source strings.Builder
+	source.WriteString("type Base {\n Value string `json:\"value\"`\n}\n")
+	last := "Base"
+	for i := 0; i < 35; i++ {
+		name := fmt.Sprintf("Level%d", i)
+		fmt.Fprintf(&source, "type %s {\n %s\n}\n", name, last)
+		last = name
+	}
+	// Reverse order forces traversal instead of hitting pre-expanded definitions.
+	spec, err := parseText(t, source.String()+"service demo{\n@handler post\npost / ("+last+")\n}")
+	if err != nil {
+		t.Fatal(err)
+	}
+	for i, j := 0, len(spec.Types)-1; i < j; i, j = i+1, j-1 {
+		spec.Types[i], spec.Types[j] = spec.Types[j], spec.Types[i]
+	}
+	if _, err = Compile(spec); err == nil {
+		t.Fatal("unbounded composition accepted")
+	}
+}
+
+func TestGenerationConfigMissingAndLegacy(t *testing.T) {
+	dir := filepath.Join(t.TempDir(), "app")
+	if _, err := New(Options{Dir: dir, Module: "example.com/config", FrameworkDir: frameworkRoot(t)}); err != nil {
+		t.Fatal(err)
+	}
+	o := Options{Dir: dir, API: filepath.Join(dir, "api/service.api")}
+	if err := os.Remove(filepath.Join(dir, generatorConfigFile)); err != nil {
+		t.Fatal(err)
+	}
+	before := snapshot(t, dir)
+	if _, err := Generate(o); err == nil || !strings.Contains(err.Error(), "restore") {
+		t.Fatal(err)
+	}
+	if !sameFiles(before, snapshot(t, dir)) {
+		t.Fatal("missing config changed project")
+	}
+	// A genuine old manifest has never tracked a generator config.
+	var old manifest
+	if err := json.Unmarshal([]byte(readFile(t, filepath.Join(dir, manifestPath))), &old); err != nil {
+		t.Fatal(err)
+	}
+	old.GeneratorConfig = false
+	raw, _ := json.Marshal(old)
+	writeFile(t, filepath.Join(dir, manifestPath), string(raw))
+	if _, err := Generate(o); err != nil {
+		t.Fatal(err)
+	}
+	cfg, exists, err := readGeneratorConfig(dir)
+	if err != nil || !exists || cfg.Middleware != "handlers" || cfg.Repository != "none" {
+		t.Fatal(cfg, exists, err)
+	}
+	if !strings.Contains(readFile(t, filepath.Join(dir, "internal/svc/runtimeGen.go")), "middleware.Defaults()") {
+		t.Fatal("legacy registration replaced")
+	}
+}
--- a/cmd/go-omni/apigen/configLoader_test.go
+++ b/cmd/go-omni/apigen/configLoader_test.go
@@ -0,0 +1,113 @@
+package apigen
+
+import (
+	"context"
+	"encoding/json"
+	"os"
+	"os/exec"
+	"path/filepath"
+	"strings"
+	"testing"
+	"time"
+)
+
+func TestGeneratedConfigurationConsumer(t *testing.T) {
+	if os.Getenv("GO_OMNI_SCAFFOLD_INTEGRATION") != "1" {
+		t.Skip("set GO_OMNI_SCAFFOLD_INTEGRATION=1")
+	}
+	dir := filepath.Join(t.TempDir(), "app")
+	api := filepath.Join(t.TempDir(), "service.api")
+	writeFile(t, api, "service configuration {\n@handler ping\nget /ping\n}\n")
+	o := Options{API: api, Dir: dir, Module: "example.com/configuration", FrameworkDir: frameworkRoot(t)}
+	if err := generateManagedTestProject(t, o); err != nil {
+		t.Fatal(err)
+	}
+	main := readFile(t, filepath.Join(dir, "main.go"))
+	// The business only changes fields/defaults/validation, not the loading flow.
+	writeFile(t, filepath.Join(dir, "internal/config/config.go"), `package config
+ import("git.yuntuo.hk/k2safe/go-omni/config";"git.yuntuo.hk/k2safe/go-omni/logx")
+ type Config struct { Server config.Config `+"`json:\"server\"`"+`;Limit int `+"`json:\"limit\" envDefault:\"10\"`"+` }
+ func Default()Config{ c:=config.Default();c.Log.File="./var/log/app.log";c.Log.Rotation=logx.RotationConfig{Enabled:true,MaxSizeMB:10};return Config{Server:c} }
+ func(c Config)Validate()error{if err:=c.Server.Validate();err!=nil{return config.AtField("server",err)};if c.Limit<0{return config.Invalid("limit","must not be negative")};return nil}
+ `)
+	writeFile(t, filepath.Join(dir, "internal/config/loader.go"), `package config
+ import omniConfig "git.yuntuo.hk/k2safe/go-omni/config"
+ func NewLoader()(*omniConfig.Loader,error){return omniConfig.NewLoader(omniConfig.WithDecoder("custom",omniConfig.JSONDecoder{}))}
+ `)
+	svc := filepath.Join(dir, "internal/svc/serviceContext.go")
+	writeFile(t, svc, strings.Replace(readFile(t, svc), "return nil", "panic(\"dependencies must not initialize on invalid config\")", 1))
+	writeFile(t, filepath.Join(dir, "consumer_test.go"), readFile(t, "testdata/configuration/consumer_test.go"))
+	runConsumerGo(t, dir, "mod", "tidy")
+	runConsumerGo(t, dir, "test", "-race", "-count=1", "./...")
+	runConsumerGo(t, dir, "build", ".")
+	o.API = filepath.Join(dir, "api/service.api")
+	before := snapshot(t, dir)
+	for _, mode := range []string{"dry", "generate", "check"} {
+		o.DryRun = mode == "dry"
+		o.Check = mode == "check"
+		if err := generateManagedTestProject(t, o); err != nil {
+			t.Fatal(err)
+		}
+	}
+	if !sameFiles(before, snapshot(t, dir)) {
+		t.Fatal("business files overwritten")
+	}
+	if main != readFile(t, filepath.Join(dir, "main.go")) {
+		t.Fatal("main changed")
+	}
+	load := filepath.Join(dir, "internal/config/loadGen.go")
+	original := readFile(t, load)
+	writeFile(t, load, original+"\n// drift\n")
+	if err := generateManagedTestProject(t, o); err == nil {
+		t.Fatal("loadGen drift accepted")
+	}
+	writeFile(t, load, original)
+	if os.Getenv("GO_OMNI_RELEASE_CLI") != "" {
+		ctx, cancel := context.WithTimeout(context.Background(), 30*time.Second)
+		defer cancel()
+		cmd := exec.CommandContext(ctx, "go", "list", "-m", "-json", frameworkModule)
+		cmd.Dir = dir
+		cmd.Env = append(os.Environ(), "GOWORK=off")
+		data, err := cmd.CombinedOutput()
+		if err != nil {
+			t.Fatal(err, string(data))
+		}
+		var dependency struct {
+			Version, Sum string
+			Replace      any
+		}
+		if err = json.Unmarshal(data, &dependency); err != nil {
+			t.Fatal(err)
+		}
+		if dependency.Version != os.Getenv("GO_OMNI_RELEASE_VERSION") || dependency.Replace != nil || dependency.Sum == "" {
+			t.Fatal("not a remote consumer")
+		}
+		t.Logf("remote framework %s checksum %s; no local replace", dependency.Version, dependency.Sum)
+	}
+}
+func TestConfigLoadMigrationGuard(t *testing.T) {
+	dir := filepath.Join(t.TempDir(), "app")
+	o := Options{Dir: dir, Module: "example.com/upgrade", FrameworkDir: frameworkRoot(t)}
+	if _, err := New(o); err != nil {
+		t.Fatal(err)
+	}
+	o.API = filepath.Join(dir, "api/service.api")
+	matches, err := filepath.Glob(filepath.Join(dir, "api/*.api"))
+	if err != nil || len(matches) != 1 {
+		t.Fatal(matches, err)
+	}
+	o.API = matches[0]
+	writeFile(t, filepath.Join(dir, "internal/config/legacy.go"), "package config\nfunc Load(path string)(Config,error){return Default(),nil}\n")
+	before := snapshot(t, dir)
+	for _, mode := range []string{"dry", "generate", "check"} {
+		o.DryRun = mode == "dry"
+		o.Check = mode == "check"
+		_, err := Generate(o)
+		if err == nil || !strings.Contains(err.Error(), "CONFIG.md") {
+			t.Fatal("missing migration diagnostic", err)
+		}
+		if !sameFiles(before, snapshot(t, dir)) {
+			t.Fatal("migration guard changed files")
+		}
+	}
+}
--- a/cmd/go-omni/apigen/contractMetadata.go
+++ b/cmd/go-omni/apigen/contractMetadata.go
@@ -213,7 +213,7 @@ func decorateDocument(doc map[string]any, spec *Spec, bindings map[string]*contr
 		if len(r.Errors) == 0 && documentRegistry != nil {
 			registry = documentRegistry
 			op["x-omni-error-catalog-scope"] = "app"
-			for key, definition := range registry.Catalog().Definitions {
+			for key, definition := range documentRouteCatalog(spec, r).Definitions {
 				grouped[definition.Status] = append(grouped[definition.Status], ErrorDefinition{Name: key, Code: key, Status: definition.Status, Message: definition.Message, BusinessCode: definition.Code, Params: definition.Params})
 			}
 		}
--- a/cmd/go-omni/apigen/copyConsumer_test.go
+++ b/cmd/go-omni/apigen/copyConsumer_test.go
@@ -0,0 +1,118 @@
+package apigen
+
+import (
+	"context"
+	"encoding/json"
+	"fmt"
+	"os"
+	"os/exec"
+	"path/filepath"
+	"strings"
+	"testing"
+	"time"
+)
+
+func runConsumerGo(t *testing.T, dir string, args ...string) {
+	t.Helper()
+	ctx, cancel := context.WithTimeout(context.Background(), 90*time.Second)
+	defer cancel()
+	cmd := exec.CommandContext(ctx, "go", args...)
+	cmd.Dir = dir
+	cmd.Env = append(os.Environ(), "GOWORK=off")
+	if out, err := cmd.CombinedOutput(); err != nil {
+		t.Fatalf("go %v: %v\n%s", args, err, out)
+	}
+}
+func TestCopyxThreeEndpointConsumer(t *testing.T) {
+	if os.Getenv("GO_OMNI_SCAFFOLD_INTEGRATION") != "1" {
+		t.Skip("set GO_OMNI_SCAFFOLD_INTEGRATION=1")
+	}
+	dir := filepath.Join(t.TempDir(), "app")
+	o := Options{API: filepath.Join(frameworkRoot(t), "cmd/go-omni/apigen/testdata/composition/service.api"), Dir: dir, Module: "example.com/composition", FrameworkDir: frameworkRoot(t)}
+	if err := generateManagedTestProject(t, o); err != nil {
+		t.Fatal(err)
+	}
+	for path, fixture := range map[string]string{
+		"internal/amount/money.go": "amount.go", "internal/domain/employee.go": "domain.go", "internal/convert/fields.go": "converters.go", "internal/convert/copy.go": "copy.go",
+		"internal/middleware/dependencies.go": "dependencies.go", "internal/middleware/accessFactory.go": "accessFactory.go", "internal/svc/client.go": "client.go", "consumer_test.go": "consumer_test.go",
+	} {
+		writeFile(t, filepath.Join(dir, path), readFile(t, "testdata/composition/"+fixture))
+	}
+	svcFile := filepath.Join(dir, "internal/svc/serviceContext.go")
+	source := strings.Replace(readFile(t, svcFile), "type ServiceContext struct {", "type ServiceContext struct {\n client *Client", 1)
+	source = strings.Replace(source, "return nil", "return c.initClient(ctx)", 1)
+	writeFile(t, svcFile, source)
+	configFile := filepath.Join(dir, "internal/config/config.go")
+	writeFile(t, configFile, strings.Replace(readFile(t, configFile), "type Config struct {", "type Config struct {\n FactoryMode string `json:\"factoryMode\"`", 1))
+	for _, group := range []string{"Enterprise", "Tenant", "Admin"} {
+		text := fmt.Sprintf(`package %s
+import("context";"example.com/composition/internal/types";"example.com/composition/internal/convert";"example.com/composition/internal/domain")
+func(s *Logic)Save(ctx context.Context,req *types.%sRequest)(*types.EmployeeResponse,error){
+ input,err:=convert.Employee(*req);if err!=nil{return nil,err}
+ result,err:=convert.Response(domain.Result{Employee:input,ID:9007199254740993});if err!=nil{return nil,err};return &result,nil
+}
+`, strings.ToLower(group), group)
+		writeFile(t, filepath.Join(dir, "internal/logic", strings.ToLower(group), "save.go"), text)
+	}
+	runConsumerGo(t, dir, "mod", "tidy")
+	runConsumerGo(t, dir, "test", "-race", "-count=1", "./...")
+	o.API = filepath.Join(dir, "api/service.api")
+	before := snapshot(t, dir)
+	o.DryRun = true
+	if err := generateManagedTestProject(t, o); err != nil {
+		t.Fatal(err)
+	}
+	o.DryRun = false
+	if err := generateManagedTestProject(t, o); err != nil {
+		t.Fatal(err)
+	}
+	o.Check = true
+	if err := generateManagedTestProject(t, o); err != nil {
+		t.Fatal(err)
+	}
+	if !sameFiles(before, snapshot(t, dir)) {
+		t.Fatal("generation changed business files")
+	}
+	if _, err := os.Stat(filepath.Join(dir, "internal/mapping")); !os.IsNotExist(err) {
+		t.Fatal("mapping directory generated")
+	}
+	// Adding a common field requires one contract edit and one independent
+	// business field. Three endpoint converters need no new rules.
+	contract := readFile(t, o.API)
+	contract = strings.Replace(contract, "type SalaryFields {", "type SalaryFields {\n Note string `json:\"note,optional\"`", 1)
+	writeFile(t, o.API, contract)
+	domainPath := filepath.Join(dir, "internal/domain/employee.go")
+	writeFile(t, domainPath, strings.Replace(readFile(t, domainPath), "type Employee struct {", "type Employee struct {\n Note string", 1))
+	o.Check = false
+	if err := generateManagedTestProject(t, o); err != nil {
+		t.Fatal(err)
+	}
+	o.Check = true
+	if err := generateManagedTestProject(t, o); err != nil {
+		t.Fatal(err)
+	}
+	runConsumerGo(t, dir, "test", "-race", "-count=1", "./...")
+	runConsumerGo(t, dir, "build", ".")
+	if os.Getenv("GO_OMNI_RELEASE_CLI") != "" {
+		ctx, cancel := context.WithTimeout(context.Background(), 30*time.Second)
+		defer cancel()
+		cmd := exec.CommandContext(ctx, "go", "list", "-m", "-json", frameworkModule)
+		cmd.Dir = dir
+		cmd.Env = append(os.Environ(), "GOWORK=off")
+		data, err := cmd.CombinedOutput()
+		if err != nil {
+			t.Fatal(err, string(data))
+		}
+		var dependency struct {
+			Version, Sum string
+			Replace      any
+		}
+		if err = json.Unmarshal(data, &dependency); err != nil {
+			t.Fatal(err)
+		}
+		if dependency.Version != os.Getenv("GO_OMNI_RELEASE_VERSION") || dependency.Replace != nil || dependency.Sum == "" {
+			t.Fatal("not a fixed remote consumer")
+		}
+		t.Logf("remote framework %s checksum %s; no local replace", dependency.Version, dependency.Sum)
+	}
+}
--- a/cmd/go-omni/apigen/documentRefs.go
+++ b/cmd/go-omni/apigen/documentRefs.go
@@ -0,0 +1,86 @@
+package apigen
+
+import "encoding/json"
+
+// compactDocument only replaces standard OpenAPI Reference Object positions.
+// Payloads (including examples containing a literal "$ref") are never walked.
+// Mixed HTTP 200 responses retain both success and error alternatives.
+func compactDocument(doc map[string]any) {
+	type slot struct {
+		parent map[string]any
+		key    string
+	}
+	components := doc["components"].(map[string]any)
+	var responses, schemas, examples []slot
+	for _, path := range doc["paths"].(map[string]any) {
+		for _, value := range path.(map[string]any) {
+			op, ok := value.(map[string]any)
+			if !ok {
+				continue
+			}
+			rs, _ := op["responses"].(map[string]any)
+			for status := range rs {
+				responses = append(responses, slot{rs, status})
+
+			}
+		}
+	}
+	factor := func(kind string, slots []slot) {
+		counts := map[string]int{}
+		for _, s := range slots {
+			raw, _ := json.Marshal(s.parent[s.key])
+			counts[string(raw)]++
+		}
+		shared, _ := components[kind].(map[string]any)
+		if shared == nil {
+			shared = map[string]any{}
+		}
+		for _, s := range slots {
+			raw, _ := json.Marshal(s.parent[s.key])
+			count := counts[string(raw)]
+			if count < 2 {
+				continue
+			}
+			name := "Omni_" + digest(raw)
+			ref := map[string]any{"$ref": "#/components/" + kind + "/" + name}
+			refJSON, _ := json.Marshal(ref)
+			// Keep small objects inline if components would increase size.
+			if (count-1)*len(raw) <= count*len(refJSON)+len(name)+4 {
+				continue
+			}
+			shared[name] = s.parent[s.key]
+			s.parent[s.key] = map[string]any{"$ref": "#/components/" + kind + "/" + name}
+		}
+		if len(shared) > 0 {
+			components[kind] = shared
+		}
+	}
+
+	// Share whole responses before counting inner objects. Otherwise a catalog
+	// copied across 100 routes can create hundreds of unnecessary components
+	// that only one shared response ultimately uses.
+	factor("responses", responses)
+	collectMedia := func(value any) {
+		resp := value.(map[string]any)
+		content, _ := resp["content"].(map[string]any)
+		for _, value := range content {
+			media := value.(map[string]any)
+			if media["schema"] != nil {
+				schemas = append(schemas, slot{media, "schema"})
+			}
+			es, _ := media["examples"].(map[string]any)
+			for name := range es {
+				examples = append(examples, slot{es, name})
+			}
+		}
+	}
+	for _, s := range responses {
+		collectMedia(s.parent[s.key])
+	}
+	sharedResponses, _ := components["responses"].(map[string]any)
+	for _, resp := range sharedResponses {
+		collectMedia(resp)
+	}
+	factor("examples", examples)
+	factor("schemas", schemas)
+}
--- a/cmd/go-omni/apigen/documentRefs_test.go
+++ b/cmd/go-omni/apigen/documentRefs_test.go
@@ -0,0 +1,107 @@
+package apigen
+
+import (
+	"encoding/json"
+	"fmt"
+	apierrors "git.yuntuo.hk/k2safe/go-omni/errors"
+	"strings"
+	"testing"
+)
+
+func TestSharedErrorDocumentReferences(t *testing.T) {
+	source := `@app(defaultResponse: Common)
+response Common(codeType:int32;successCode:0;errorCode:9999;messageField:msg;dataMode:always)
+service demo {
+`
+	for i := 0; i < 16; i++ {
+		kind := "string"
+		if i%2 == 0 {
+			kind = "int64"
+		}
+		source += fmt.Sprintf("@handler list%d\nget /list%d returns ([]%s)\n", i, i, kind)
+	}
+	source += "}\n"
+	spec, err := parseText(t, source)
+	if err != nil {
+		t.Fatal(err)
+	}
+	catalog := apierrors.Catalog{DefaultStatus: 400, Definitions: map[string]apierrors.Definition{}}
+	for i := 0; i < 80; i++ {
+		status := 400
+		if i%2 == 0 {
+			status = 200
+		}
+		catalog.Definitions[fmt.Sprintf("ERROR_%d", i)] = apierrors.Definition{Status: status, Code: 400000 + i, Message: strings.Repeat("说明", 40) + "{label}不能超过{max}个字符", Params: []apierrors.Parameter{{Name: "label", Type: "string", Example: "企业名称"}, {Name: "max", Type: "int", Example: 100}}}
+	}
+	spec.DocumentCatalog = &catalog
+	compiled, err := Compile(spec)
+	if err != nil {
+		t.Fatal(err)
+	}
+	var raw map[string]any
+	if err = json.Unmarshal(compiled.Document, &raw); err != nil {
+		t.Fatal(err)
+	}
+	components := raw["components"].(map[string]any)
+	for _, kind := range []string{"responses", "examples"} {
+		if len(components[kind].(map[string]any)) == 0 {
+			t.Fatal("missing shared", kind)
+		}
+	}
+	expanded := document(t, compiled)
+	for i := 0; i < 16; i++ {
+		responses := operation(t, expanded, fmt.Sprintf("/list%d", i), "get")["responses"].(map[string]any)
+		for _, status := range []string{"200", "400"} {
+			media := responses[status].(map[string]any)["content"].(map[string]any)["application/json"].(map[string]any)
+			if len(media["examples"].(map[string]any)) != 40 {
+				t.Fatal("examples lost")
+			}
+			if status == "200" {
+				choices := media["schema"].(map[string]any)["anyOf"].([]any)
+				if len(choices) != 2 || choices[0].(map[string]any)["properties"].(map[string]any)["data"].(map[string]any)["type"] != "array" {
+					t.Fatal("200 success shape lost")
+				}
+			}
+			for _, example := range media["examples"].(map[string]any) {
+				value := example.(map[string]any)["value"].(map[string]any)
+				if _, ok := value["data"]; !ok || value["data"] != nil || !strings.Contains(value["msg"].(string), "企业名称不能超过100个字符") {
+					t.Fatal(value)
+				}
+			}
+		}
+	}
+	expandedBytes, _ := json.MarshalIndent(expanded, "", "  ")
+	if len(compiled.Document)*5 > len(expandedBytes) {
+		t.Fatalf("poor dedup: %d vs %d", len(compiled.Document), len(expandedBytes))
+	}
+	again, err := Compile(spec)
+	if err != nil || string(again.Document) != string(compiled.Document) {
+		t.Fatal("non-deterministic document", err)
+	}
+	before, _ := json.Marshal(raw)
+	compactDocument(raw)
+	data, _ := json.Marshal(raw)
+	if string(data) != string(before) {
+		t.Fatal("compaction not idempotent")
+	}
+}
+
+func TestSharedSchemasAndLiteralExampleReference(t *testing.T) {
+	doc := map[string]any{"components": map[string]any{}, "paths": map[string]any{}}
+	paths := doc["paths"].(map[string]any)
+	for _, name := range []string{"first", "second", "third"} {
+		schema := map[string]any{"type": "object", "description": strings.Repeat("schema description ", 40)}
+		example := map[string]any{"summary": strings.Repeat("example ", 50), "value": map[string]any{"$ref": "literal business field"}}
+		paths["/"+name] = map[string]any{"get": map[string]any{"responses": map[string]any{"200": map[string]any{"description": name, "content": map[string]any{"application/json": map[string]any{"schema": schema, "examples": map[string]any{"same": example}}}}}}}
+	}
+	compactDocument(doc)
+	components := doc["components"].(map[string]any)
+	if len(components["schemas"].(map[string]any)) != 1 {
+		t.Fatal("schema not shared")
+	}
+	for _, example := range components["examples"].(map[string]any) {
+		if example.(map[string]any)["value"].(map[string]any)["$ref"] != "literal business field" {
+			t.Fatal("payload reference interpreted")
+		}
+	}
+}
--- a/cmd/go-omni/apigen/generate.go
+++ b/cmd/go-omni/apigen/generate.go
@@ -19,11 +19,16 @@ import (
 )

 const frameworkModule = "git.yuntuo.hk/k2safe/go-omni"
-const minimumVersion = "v0.15.0-preview"
+
+// Runtime-only releases need not raise the managed template compatibility floor.
+const minimumVersion = "v0.20.0-preview"
+const currentVersion = "v0.21.0-preview"
 const generatedHeader = "// Code generated by go-omni api. DO NOT EDIT.\n"

 type Options struct {
+	generation                                                             GeneratorConfig
 	lockHeld                                                               bool
+	documentCatalogs                                                       map[string][]byte
 	Database, Storage                                                      string
 	API, Dir, Module, FrameworkDir, FrameworkVersion, LogOutput, LogFormat string
 	Check                                                                  bool
@@ -48,7 +53,7 @@ func Generate(o Options) (Output, error) {
 	if o.API == "" || o.Dir == "" {
 		return Output{}, errors.New("--api and --dir are required")
 	}
-	spec, err := Parse(o.API)
+	spec, err := parseWithCatalogs(o.API, o.documentCatalogs)
 	if err != nil {
 		return Output{}, err
 	}
@@ -96,9 +101,17 @@ func generate(o Options, c *Compiled, starter bool) (Output, error) {
 		return Output{}, err
 	}
 	o.Dir = directory
+	genConfig, hasGenConfig, err := readGeneratorConfig(directory)
+	if err != nil {
+		return Output{}, err
+	}
+	o.generation = genConfig
 	if err = checkRuntimeExtension(directory); err != nil {
 		return Output{}, err
 	}
+	if err = checkConfigLoadExtension(directory); err != nil {
+		return Output{}, err
+	}
 	for _, r := range c.Spec.Routes {
 		if !r.Manual {
 			path := filepath.Join(directory, "internal/handler", r.Group, lower(r.Handler)+"Manual.go")
@@ -145,13 +158,13 @@ func generate(o Options, c *Compiled, starter bool) (Output, error) {
 					if !filepath.IsAbs(path) {
 						path = filepath.Join(directory, path)
 					}
-					if _, err := os.Stat(filepath.Join(path, "lifecycle", "runtime.go")); err == nil {
+					if source, err := os.ReadFile(filepath.Join(path, "config", "loader.go")); err == nil && strings.Contains(string(source), "func NewLoader(") {
 						localCurrent = true
 					}
 				}
 			}
 			if !localCurrent {
-				return Output{}, fmt.Errorf("existing framework dependency predates the generated phased lifecycle support; use %s or a current local replacement", minimumVersion)
+				return Output{}, fmt.Errorf("existing framework dependency predates the generated configuration helpers; use %s or a current local replacement", minimumVersion)
 			}
 		}
 		if o.FrameworkDir != "" {
@@ -191,6 +204,10 @@ func generate(o Options, c *Compiled, starter bool) (Output, error) {
 	for name, data := range base {
 		seeds[name] = data
 	}
+	if !hasGenConfig {
+		raw, _ := json.MarshalIndent(genConfig, "", "  ")
+		seeds[generatorConfigFile] = append(raw, '\n')
+	}
 	// The API source remains developer-owned. A relocated project regenerates
 	// from its own api/ tree, including all imports.
 	entry := "api/" + c.Spec.Entry
@@ -241,8 +258,17 @@ func generate(o Options, c *Compiled, starter bool) (Output, error) {
 			}
 		}
 	}
+	currentConfig, stillExists, err := readGeneratorConfig(directory)
+	if err != nil {
+		return Output{}, err
+	}
+	beforeConfig, _ := json.Marshal(genConfig)
+	afterConfig, _ := json.Marshal(currentConfig)
+	if hasGenConfig != stillExists || genConfig.inputDigest != currentConfig.inputDigest || string(beforeConfig) != string(afterConfig) {
+		return Output{}, errors.New("generation configuration changed during generation; retry")
+	}
 	out, err := apply(directory, o.Module, entry, generated, seeds, o.Check, o.DryRun, o.profile(), snapshotContract(c.Spec), o.lockHeld)
-	expectedVersion := minimumVersion
+	expectedVersion := currentVersion
 	if info, ok := debug.ReadBuildInfo(); ok && info.Main.Path == frameworkModule && info.Main.Sum != "" && semver.IsValid(info.Main.Version) {
 		expectedVersion = info.Main.Version
 	}
@@ -281,7 +307,7 @@ func moduleFile(o Options) ([]byte, error) {
 		if info, ok := debug.ReadBuildInfo(); ok && info.Main.Path == frameworkModule && info.Main.Sum != "" {
 			version = info.Main.Version
 		} else {
-			version = minimumVersion
+			version = currentVersion
 		}
 	}
 	if !semver.IsValid(version) || semver.Major(version) != "v0" && semver.Major(version) != "v1" {
@@ -454,7 +480,7 @@ func renderProject(o Options, c *Compiled, starter bool) (map[string][]byte, map
 				continue
 			}
 			hasAutomatic = true
-			needsTypes = needsTypes || r.Request != "" || responseGoType(r.Response) != ""
+			needsTypes = needsTypes || r.Request != "" || responseNeedsTypes(r.Response)
 			needsBinder = needsBinder || !r.CustomBinding
 		}
 		text += fmt.Sprintf("%q;%q;", frameworkModule+"/httpx", o.Module+"/internal/svc")
@@ -570,7 +596,7 @@ func renderProject(o Options, c *Compiled, starter bool) (map[string][]byte, map
 				}
 			}
 			service := fmt.Sprintf("package %s\nimport(\"context\"; apierrors %q;", packageName, frameworkModule+"/errors")
-			if r.Request != "" || responseGoType(r.Response) != "" {
+			if r.Request != "" || responseNeedsTypes(r.Response) {
 				service += fmt.Sprintf("%q;", o.Module+"/internal/types")
 			}
 			if streamingBody || r.Produces != "" {
@@ -601,7 +627,9 @@ func renderProject(o Options, c *Compiled, starter bool) (map[string][]byte, map
 		}
 		put(generated, "internal/handler/"+group+"/handlersGen.go", generatedHeader+text)
 		put(seeds, "internal/logic/"+group+"/logic.go", fmt.Sprintf("package %s\nimport %q\ntype Logic struct {deps *svc.ServiceContext}\nfunc New(deps *svc.ServiceContext)*Logic{return &Logic{deps:deps}}\n", packageName, o.Module+"/internal/svc"))
-		put(seeds, "internal/repository/"+group+"/repository.go", "// Package "+packageName+" owns persistence contracts for this business group.\n// Define repository interfaces and implementations here; HTTP DTOs do not\n// determine a database schema. This file is never overwritten.\npackage "+packageName+"\n")
+		if o.generation.Repository == "group" {
+			put(seeds, "internal/repository/"+group+"/repository.go", "// Package "+packageName+" owns persistence contracts for this business group.\n// Define repository interfaces and implementations here; HTTP DTOs do not\n// determine a database schema. This file is never overwritten.\npackage "+packageName+"\n")
+		}
 	}
 	put(generated, "internal/handler/routesGen.go", generatedHeader+"package handler\n"+imports+")\n"+routes+"return nil\n}\n")
 	registry := "package middleware\nimport " + strconv.Quote(frameworkModule+"/httpx") + "\nfunc Defaults()map[string]httpx.Middleware{return map[string]httpx.Middleware{\n"
@@ -610,6 +638,9 @@ func renderProject(o Options, c *Compiled, starter bool) (map[string][]byte, map
 		put(seeds, "internal/middleware/"+lower(m)+".go", fmt.Sprintf("package middleware\nimport(%q; apierrors %q)\n// %s is a developer-owned hook. Implement it before enabling this route.\nfunc %s(next httpx.Handler)httpx.Handler{return func(c *httpx.Context)error {return apierrors.New(501,\"MIDDLEWARE_NOT_IMPLEMENTED\",\"middleware is not implemented\")}}\n", frameworkModule+"/httpx", frameworkModule+"/errors", upper(m), upper(m)))
 	}
 	put(generated, "internal/middleware/registryGen.go", generatedHeader+registry+"}}\n")
+	if o.generation.Middleware == "factories" {
+		renderMiddlewareFactories(middlewareNames, generated, seeds)
+	}
 	for name, source := range baseTemplates {
 		content := strings.ReplaceAll(source, "MODULE", o.Module)
 		content = strings.ReplaceAll(content, "LOGFORMAT", o.LogFormat)
@@ -629,6 +660,16 @@ func renderProject(o Options, c *Compiled, starter bool) (map[string][]byte, map
 		return nil, nil, err
 	}
 	for name, data := range infra {
+		if o.generation.Middleware == "factories" && name == "internal/svc/runtimeGen.go" {
+			formatted, err := format.Source(data)
+			if err != nil {
+				return nil, nil, err
+			}
+			source := string(formatted)
+			source = strings.Replace(source, "Middlewares: middleware.Defaults(),", "", 1)
+			source = strings.Replace(source, "return c, nil", "if len(c.Middlewares) != 0 { return nil, errors.New(\"factory middleware is registered automatically; remove manual Middlewares assignments from Init\") }\nc.Middlewares, err = middleware.New(c)\nif err != nil { return nil, err }\nreturn c, nil", 1)
+			data = []byte(source)
+		}
 		if strings.HasSuffix(name, "Gen.go") {
 			generated[name] = append([]byte(generatedHeader), data...)
 		} else {
--- a/cmd/go-omni/apigen/generatorConfig.go
+++ b/cmd/go-omni/apigen/generatorConfig.go
@@ -0,0 +1,110 @@
+package apigen
+
+import (
+	"crypto/sha256"
+	"encoding/json"
+	"errors"
+	"fmt"
+	"io"
+	"os"
+	"path/filepath"
+	"strings"
+
+	apierrors "git.yuntuo.hk/k2safe/go-omni/errors"
+)
+
+const generatorConfigFile = "omni.gen.json"
+
+// GeneratorConfig contains developer-owned scaffolding options only.
+type GeneratorConfig struct {
+	Repository  string `json:"repository,omitempty"`
+	Middleware  string `json:"middleware,omitempty"`
+	inputDigest string
+}
+
+func readGeneratorConfig(root string) (GeneratorConfig, bool, error) {
+	cfg := GeneratorConfig{Repository: "none", Middleware: "factories"}
+	if err := safePath(root, generatorConfigFile); err != nil {
+		return cfg, false, err
+	}
+	stat, err := os.Lstat(filepath.Join(root, generatorConfigFile))
+	if errors.Is(err, os.ErrNotExist) {
+		// Existing projects keep their handwritten middleware signature until they
+		// explicitly select factories; do not rewrite or adopt developer files.
+		if raw, e := os.ReadFile(filepath.Join(root, manifestPath)); e == nil {
+			var previous manifest
+			if err := json.Unmarshal(raw, &previous); err != nil {
+				return cfg, false, err
+			}
+			if previous.GeneratorConfig {
+				return cfg, false, errors.New("omni.gen.json is missing; restore the project-owned generation options before regenerating")
+			}
+			cfg.Middleware = "handlers"
+		} else if !errors.Is(e, os.ErrNotExist) {
+			return cfg, false, e
+		}
+		return cfg, false, nil
+	}
+	if err != nil {
+		return cfg, false, err
+	}
+	if !stat.Mode().IsRegular() || stat.Size() > 1<<20 {
+		return cfg, false, errors.New("omni.gen.json must be a regular file of at most 1 MiB")
+	}
+	raw, err := readGeneratorConfigFile(root, generatorConfigFile)
+	if err != nil {
+		return cfg, false, err
+	}
+	var keys map[string]json.RawMessage
+	if err = apierrors.DecodeCatalogJSON(raw, &keys); err != nil {
+		return cfg, false, fmt.Errorf("omni.gen.json: %w", err)
+	}
+	for _, key := range []string{"mappings", "mappingFiles"} {
+		if _, exists := keys[key]; exists {
+			return cfg, false, errors.New("mapping generation was removed: migrate callers to copyx or ordinary Go, remove mappings/mappingFiles from omni.gen.json, then remove internal/mapping/mappingsGen.go; see COPY.md")
+		}
+	}
+	if err = apierrors.DecodeCatalogJSON(raw, &cfg); err != nil {
+		return cfg, false, fmt.Errorf("omni.gen.json: %w", err)
+	}
+	digest := sha256.Sum256(raw)
+	cfg.inputDigest = fmt.Sprintf("%x", digest)
+	if cfg.Repository != "none" && cfg.Repository != "group" {
+		return cfg, false, errors.New("omni.gen.json: repository must be none or group")
+	}
+	if cfg.Middleware != "factories" && cfg.Middleware != "handlers" {
+		return cfg, false, errors.New("omni.gen.json: middleware must be factories or handlers")
+	}
+	return cfg, true, nil
+}
+
+// Read through a bounded reader as well as checking stat: a growing file cannot
+// make configuration loading unbounded. safePath also rejects symlink escapes.
+func readGeneratorConfigFile(root, name string) ([]byte, error) {
+	if err := safePath(root, name); err != nil {
+		return nil, err
+	}
+	f, err := os.Open(filepath.Join(root, filepath.FromSlash(name)))
+	if err != nil {
+		return nil, fmt.Errorf("%s: %w", name, err)
+	}
+	defer f.Close()
+	stat, err := f.Stat()
+	if err != nil {
+		return nil, err
+	}
+	if !stat.Mode().IsRegular() || stat.Size() > 1<<20 {
+		return nil, fmt.Errorf("%s must be a regular file of at most 1 MiB", name)
+	}
+	raw, err := io.ReadAll(io.LimitReader(f, (1<<20)+1))
+	if err != nil {
+		return nil, err
+	}
+	if len(raw) > 1<<20 {
+		return nil, fmt.Errorf("%s exceeds 1 MiB", name)
+	}
+	if trimmed := strings.TrimSpace(string(raw)); !strings.HasPrefix(trimmed, "{") {
+		return nil, fmt.Errorf("%s must contain a JSON object", name)
+	}
+	return raw, nil
+}
--- a/cmd/go-omni/apigen/generatorConfig_test.go
+++ b/cmd/go-omni/apigen/generatorConfig_test.go
@@ -0,0 +1,96 @@
+package apigen
+
+import (
+	"encoding/json"
+	"io"
+	"os"
+	"path/filepath"
+	"strings"
+	"testing"
+)
+
+func TestWorkspaceRejectsRemovedMappingWithoutWrites(t *testing.T) {
+	root := t.TempDir()
+	for _, name := range []string{"one", "two"} {
+		if _, err := New(Options{Dir: filepath.Join(root, name), Module: "example.com/" + name, FrameworkDir: frameworkRoot(t)}); err != nil {
+			t.Fatal(err)
+		}
+	}
+	firstAPI := filepath.Join(root, "one/api/service.api")
+	writeFile(t, firstAPI, strings.Replace(readFile(t, firstAPI), "Greet a visitor", "Changed description", 1))
+	writeFile(t, filepath.Join(root, "two", generatorConfigFile), `{"mappingFiles":["../../private.json"]}`)
+	workspace := filepath.Join(root, "omni.workspace.json")
+	writeFile(t, workspace, `{"services":[{"dir":"one"},{"dir":"two"}]}`)
+	before := snapshot(t, root)
+	for _, operation := range []string{"generate", "check"} {
+		if err := Workspace(workspace, operation, io.Discard); err == nil || !strings.Contains(err.Error(), "mapping generation was removed") {
+			t.Fatal(operation, err)
+		}
+		if !sameFiles(before, snapshot(t, root)) {
+			t.Fatal("workspace migration failure wrote files")
+		}
+	}
+}
+
+func TestRemovedMappingConfiguration(t *testing.T) {
+	dir := filepath.Join(t.TempDir(), "project")
+	if _, err := New(Options{Dir: dir, Module: "example.com/removed", FrameworkDir: frameworkRoot(t)}); err != nil {
+		t.Fatal(err)
+	}
+	for _, raw := range []string{`{"mappings":[]}`, `{"mappingFiles":[]}`, `{"mappings":null}`, `{"mappingFiles":["../../private.json"]}`} {
+		writeFile(t, filepath.Join(dir, generatorConfigFile), raw)
+		before := snapshot(t, dir)
+		for _, o := range []Options{{Dir: dir}, {Dir: dir, Check: true}, {Dir: dir, DryRun: true}} {
+			o.API = filepath.Join(dir, "api/service.api")
+			if _, err := Generate(o); err == nil || !strings.Contains(err.Error(), "mapping generation was removed") {
+				t.Fatal(err)
+			}
+			if !sameFiles(before, snapshot(t, dir)) {
+				t.Fatal("rejected config wrote project")
+			}
+		}
+	}
+}
+func TestOldMappingFileRequiresExplicitMigration(t *testing.T) {
+	dir := filepath.Join(t.TempDir(), "project")
+	if _, err := New(Options{Dir: dir, Module: "example.com/removed", FrameworkDir: frameworkRoot(t)}); err != nil {
+		t.Fatal(err)
+	}
+	name := "internal/mapping/mappingsGen.go"
+	body := generatedHeader + "package mapping\n"
+	writeFile(t, filepath.Join(dir, name), body)
+	var m manifest
+	if err := json.Unmarshal([]byte(readFile(t, filepath.Join(dir, manifestPath))), &m); err != nil {
+		t.Fatal(err)
+	}
+	m.Generated[name] = digest([]byte(body))
+	raw, _ := json.Marshal(m)
+	writeFile(t, filepath.Join(dir, manifestPath), string(raw))
+	before := snapshot(t, dir)
+	o := Options{Dir: dir, API: filepath.Join(dir, "api/service.api")}
+	for _, mode := range []string{"generate", "check", "dry-run"} {
+		o.Check = mode == "check"
+		o.DryRun = mode == "dry-run"
+		if _, err := Generate(o); err == nil || !strings.Contains(err.Error(), "mapping generation was removed") {
+			t.Fatal(err)
+		}
+		if !sameFiles(before, snapshot(t, dir)) {
+			t.Fatal("legacy file deleted or project changed")
+		}
+	}
+	if err := os.Remove(filepath.Join(dir, name)); err != nil {
+		t.Fatal(err)
+	}
+	o.Check = false
+	o.DryRun = false
+	if _, err := Generate(o); err != nil {
+		t.Fatal(err)
+	}
+	o.Check = true
+	if _, err := Generate(o); err != nil {
+		t.Fatal(err)
+	}
+	if strings.Contains(readFile(t, filepath.Join(dir, manifestPath)), name) {
+		t.Fatal("old ownership retained")
+	}
+}
--- a/cmd/go-omni/apigen/managed_test.go
+++ b/cmd/go-omni/apigen/managed_test.go
@@ -170,12 +170,15 @@ func generateManagedTestProject(t *testing.T, o Options) error {
 		_, err := Generate(o)
 		return err
 	}
-	ctx, cancel := context.WithTimeout(context.Background(), 30*time.Second)
+	ctx, cancel := context.WithTimeout(context.Background(), 90*time.Second)
 	defer cancel()
 	args := []string{"api", "generate", "--api", o.API, "--dir", o.Dir, "--module", o.Module}
 	if o.Check {
 		args = append(args, "--check")
 	}
+	if o.DryRun {
+		args = append(args, "--dry-run")
+	}
 	cmd := exec.CommandContext(ctx, cli, args...)
 	cmd.Dir = filepath.Dir(o.Dir)
 	if data, err := cmd.CombinedOutput(); err != nil {
--- a/cmd/go-omni/apigen/metadata_test.go
+++ b/cmd/go-omni/apigen/metadata_test.go
@@ -74,7 +74,7 @@ func document(t *testing.T, c *Compiled) map[string]any {
 	if err := json.Unmarshal(c.Document, &doc); err != nil {
 		t.Fatal(err)
 	}
-	return doc
+	return expandDocumentRefs(t, doc, doc).(map[string]any)
 }
 func operation(t *testing.T, doc map[string]any, path, method string) map[string]any {
 	t.Helper()
@@ -238,6 +238,7 @@ func TestDeclaredContractConsumer(t *testing.T) {
 	source := filepath.Join(root, "input/service.api")
 	writeFile(t, source, declaredAPI)
 	dir := filepath.Join(root, "project")
+	writeFile(t, filepath.Join(dir, generatorConfigFile), `{"middleware":"handlers"}`)
 	if _, err := Generate(Options{API: source, Dir: dir, Module: "example.com/dx", FrameworkDir: frameworkRoot(t)}); err != nil {
 		t.Fatal(err)
 	}
@@ -303,3 +304,21 @@ func TestAuthMetadataWithParameterNamePrefixes(t *testing.T) {
 		t.Fatal("auth metadata lost")
 	}
 }
+
+// Existing semantic assertions resolve the standard local references emitted
+// by the compiler. documentRefs_test additionally checks the actual references.
+func expandDocumentRefs(t *testing.T, doc map[string]any, v any) any {
+ t.Helper()
+ switch v:=v.(type){
+ case map[string]any:
+  if ref,ok:=v["$ref"].(string);ok && strings.HasPrefix(ref,"#/components/") && len(v)==1 {
+   var target any=doc
+   for _,part:=range strings.Split(strings.TrimPrefix(ref,"#/"),"/"){m,ok:=target.(map[string]any);if !ok{t.Fatal("invalid reference",ref)};target=m[part]}
+   if target==nil{t.Fatal("dangling reference",ref)};return expandDocumentRefs(t,doc,target)
+  }
+  out:=map[string]any{};for k,x:=range v{out[k]=expandDocumentRefs(t,doc,x)};return out
+ case []any:
+  out:=make([]any,len(v));for i,x:=range v{out[i]=expandDocumentRefs(t,doc,x)};return out
+ default:return v
+ }
+}
--- a/cmd/go-omni/apigen/middlewareFactory.go
+++ b/cmd/go-omni/apigen/middlewareFactory.go
@@ -0,0 +1,19 @@
+package apigen
+
+import "fmt"
+
+func renderMiddlewareFactories(names []string, generated, seeds map[string][]byte) {
+	// All project-specific types live behind this project-owned interface. svc
+	// implements it; middleware never imports svc (and cannot form that cycle).
+	seeds["internal/middleware/dependencies.go"] = []byte("package middleware\n// Dependencies is implemented by *svc.ServiceContext. Add typed accessors here\n// and implement them on ServiceContext. Factories borrow dependencies; register\n// their cleanup in ServiceContext.Init, not in a middleware factory.\ntype Dependencies interface {}\n")
+	text := fmt.Sprintf("package middleware\nimport(\"fmt\";%q)\n// New constructs declared middleware after ServiceContext.Init succeeds.\nfunc New(deps Dependencies)(map[string]httpx.Middleware,error){\nresult:=map[string]httpx.Middleware{}\n", frameworkModule+"/httpx")
+	if len(names) == 0 {
+		text = fmt.Sprintf("package middleware\nimport %q\nfunc New(deps Dependencies)(map[string]httpx.Middleware,error){\nresult:=map[string]httpx.Middleware{}\n", frameworkModule+"/httpx")
+	}
+	for i, name := range names {
+		delete(seeds, "internal/middleware/"+lower(name)+".go")
+		text += fmt.Sprintf("m%d,err:=New%s(deps)\nif err!=nil{return nil,fmt.Errorf(%q,err)}\nif m%d==nil{return nil,fmt.Errorf(%q)}\nresult[%q]=m%d\n", i, upper(name), "middleware "+name+": %w", i, "middleware "+name+": factory returned nil", name, i)
+		seeds["internal/middleware/"+lower(name)+"Factory.go"] = []byte(fmt.Sprintf("package middleware\nimport(\"errors\";%q)\n// New%s is project-owned. Implement this factory once; registration is generated.\n// Dependencies have already been initialized. Do not acquire owned resources here.\nfunc New%s(deps Dependencies)(httpx.Middleware,error){\nreturn nil,errors.New(%q)\n}\n", frameworkModule+"/httpx", upper(name), upper(name), "implement "+name+" middleware factory"))
+	}
+	generated["internal/middleware/registryGen.go"] = []byte(generatedHeader + text + "return result,nil\n}\n")
+}
--- a/cmd/go-omni/apigen/parse.go
+++ b/cmd/go-omni/apigen/parse.go
@@ -17,6 +17,7 @@ import (

 type Spec struct {
 	DocumentCatalog                      *apierrors.Catalog
+	DocumentErrors                       *DocumentErrors
 	SharedRoots                          map[string]SharedRoot
 	SourcePaths                          map[string]string
 	RequestPolicy                        contract.RequestPolicy
@@ -38,6 +39,8 @@ type Type struct {
 	Fields   []Field
 	Position string
 }
+
+// An empty Type denotes a named field composition, expanded before compilation.
 type Field struct{ Name, Type, Tag, Description string }
 type Route struct {
 	BoundMultipart                                           bool
@@ -72,7 +75,9 @@ type parser struct {
 	imports []string
 }

-func Parse(path string) (*Spec, error) {
+func Parse(path string) (*Spec, error) { return parseWithCatalogs(path, nil) }
+
+func parseWithCatalogs(path string, catalogs map[string][]byte) (*Spec, error) {
 	entry, err := filepath.Abs(path)
 	if err != nil {
 		return nil, err
@@ -82,11 +87,12 @@ func Parse(path string) (*Spec, error) {
 		return nil, err
 	}
 	root := filepath.Dir(entry)
-	roots, err := readSharedRoots(root)
+	shared, err := readSharedConfig(root)
 	if err != nil {
 		return nil, err
 	}
-	spec := &Spec{Version: "1.0.0", SharedRoots: roots, SourcePaths: map[string]string{}, Sources: map[string][]byte{}, Entry: filepath.Base(entry)}
+	roots := shared.Roots
+	spec := &Spec{Version: "1.0.0", DocumentErrors: shared.Errors, SharedRoots: roots, SourcePaths: map[string]string{}, Sources: map[string][]byte{}, Entry: filepath.Base(entry)}
 	visiting, visited := map[string]bool{}, map[string]bool{}
 	total := 0
 	var visit func(string, string, int) error
@@ -169,7 +175,7 @@ func Parse(path string) (*Spec, error) {
 	if err = visit(entry, "", 0); err != nil {
 		return nil, err
 	}
-	if err = readDocumentCatalog(root, spec); err != nil {
+	if err = readDocumentCatalog(root, spec, catalogs); err != nil {
 		return nil, err
 	}
 	if err = validateSharedPins(spec); err != nil {
@@ -513,7 +519,11 @@ func (p *parser) parseType() error {
 			}
 		}
 		if expression == "" {
-			return p.err("field type required; embedded types are not supported")
+			if p.tokens[p.at].kind == scanner.RawString {
+				return p.err("composed types cannot carry field tags")
+			}
+			typ.Fields = append(typ.Fields, Field{Name: name, Description: description})
+			continue
 		}
 		if p.tokens[p.at].kind != scanner.RawString {
 			return p.err("field source tag required")
--- a/cmd/go-omni/apigen/profile_test.go
+++ b/cmd/go-omni/apigen/profile_test.go
@@ -73,6 +73,8 @@ func TestConfiguration(t *testing.T){
 cfg,err:=Load("../../etc/config.yaml");if err!=nil{t.Fatal(err)}
 if cfg.Server.Log.File==""{t.Fatal("file logger absent")}
 t.Setenv("GO_OMNI_LOG_OUTPUT","stdout");cfg,err=Load("");if err!=nil||cfg.Server.Log.File!=""{t.Fatalf("override: %v",err)}
+ t.Setenv("GO_OMNI_SERVER_LOG_FILE","./explicit.log");cfg,err=Load("");if err!=nil||cfg.Server.Log.File!="./explicit.log"{t.Fatalf("canonical log file: %v",err)}
+ t.Setenv("GO_OMNI_SERVER_LOG_OUTPUT","stderr");cfg,err=Load("");if err!=nil||cfg.Server.Log.Output!="stderr"{t.Fatalf("canonical output: %v",err)}
 _=os.Getenv("unused")
 }`
 				endpoint := ""
--- a/cmd/go-omni/apigen/responseShape.go
+++ b/cmd/go-omni/apigen/responseShape.go
@@ -4,11 +4,12 @@ import (
 	"fmt"
 	"git.yuntuo.hk/k2safe/go-omni/contract"
 	"git.yuntuo.hk/k2safe/go-omni/openapi"
+	"reflect"
 	"strings"
 )

-// Response roots deliberately allow named DTOs, []DTO, *DTO and null. Keeping
-// these four shapes explicit makes nil/empty behavior uniform across encoders.
+// Response roots allow named DTOs, []DTO, []primitive, *DTO and null.
+// A nil root slice is always encoded as an empty JSON array.
 func responseShape(value string) (kind, name string) {
 	if value == "null" {
 		return "null", ""
@@ -27,6 +28,9 @@ func responseGoType(value string) string {
 		return ""
 	}
 	if kind == "array" {
+		if primitiveTypes[name] != nil {
+			return "[]" + name
+		}
 		return "[]types." + name
 	}
 	return "*types." + name
@@ -36,9 +40,25 @@ func responseDataSchema(value string, bindings map[string]*contract.Binder) (*op
 	if kind == "null" {
 		return &openapi.Schema{Type: "object", Nullable: true, Enum: []any{nil}}, nil
 	}
+	if kind == "array" && primitiveTypes[name] != nil {
+		if name == "File" {
+			return nil, fmt.Errorf("File is request-only; use a response DTO")
+		}
+		// Reuse the contract compiler, including integer bounds and byte-slice rules.
+		t := reflect.StructOf([]reflect.StructField{{Name: "Value", Type: reflect.SliceOf(primitiveTypes[name]), Tag: `json:"value"`}})
+		b, err := contract.Describe(t)
+		if err != nil {
+			return nil, err
+		}
+		s, err := b.ResponseSchema()
+		if err != nil {
+			return nil, err
+		}
+		return s.Properties["value"], nil
+	}
 	b, ok := bindings[name]
 	if !ok {
-		return nil, fmt.Errorf("unknown response DTO %q; use Name, []Name, *Name or null", name)
+		return nil, fmt.Errorf("unknown response DTO %q; use Name, []Name, []string/[]int64/[]bool/[]any, *Name or null", name)
 	}
 	s, err := b.ResponseSchema()
 	if err != nil {
@@ -52,3 +72,7 @@ func responseDataSchema(value string, bindings map[string]*contract.Binder) (*op
 	}
 	return s, nil
 }
+
+var primitiveTypes = map[string]reflect.Type{"File": reflect.TypeOf(contract.File{}), "any": reflect.TypeOf((*any)(nil)).Elem(), "string": reflect.TypeOf(""), "bool": reflect.TypeOf(false), "int": reflect.TypeOf(int(0)), "int8": reflect.TypeOf(int8(0)), "int16": reflect.TypeOf(int16(0)), "int32": reflect.TypeOf(int32(0)), "int64": reflect.TypeOf(int64(0)), "uint": reflect.TypeOf(uint(0)), "uint8": reflect.TypeOf(uint8(0)), "uint16": reflect.TypeOf(uint16(0)), "uint32": reflect.TypeOf(uint32(0)), "uint64": reflect.TypeOf(uint64(0)), "float32": reflect.TypeOf(float32(0)), "float64": reflect.TypeOf(float64(0))}
+
+func responseNeedsTypes(value string) bool { return strings.Contains(responseGoType(value), "types.") }
--- a/cmd/go-omni/apigen/response_test.go
+++ b/cmd/go-omni/apigen/response_test.go
@@ -251,6 +251,7 @@ func TestResponseTemplateConsumer(t *testing.T) {
 			t.Fatal(err)
 		}
 	}
+	writeFile(t, filepath.Join(dir, generatorConfigFile), `{"middleware":"handlers"}`)
 	generate(source, true)
 	writeFile(t, filepath.Join(dir, "response_test.go"), responseConsumerTest)
 	for _, method := range []string{"Item", "Callback", "Partner"} {
--- a/cmd/go-omni/apigen/shared.go
+++ b/cmd/go-omni/apigen/shared.go
@@ -23,48 +23,49 @@ type SharedRoot struct {
 	SHA256  string `json:"sha256,omitempty"`
 }
 type sharedConfig struct {
-	Roots map[string]SharedRoot `json:"roots"`
+	Roots  map[string]SharedRoot `json:"roots"`
+	Errors *DocumentErrors       `json:"errors,omitempty"`
 }

-func readSharedRoots(root string) (map[string]SharedRoot, error) {
+func readSharedConfig(root string) (sharedConfig, error) {
 	stat, err := os.Lstat(filepath.Join(root, importsFile))
 	if errors.Is(err, os.ErrNotExist) {
-		return nil, nil
+		return sharedConfig{}, nil
 	}
 	if err != nil {
-		return nil, err
+		return sharedConfig{}, err
 	}
 	if !stat.Mode().IsRegular() {
-		return nil, errors.New("api: shared root configuration must be a regular file")
+		return sharedConfig{}, errors.New("api: shared root configuration must be a regular file")
 	}
 	f, err := os.Open(filepath.Join(root, importsFile))
 	if errors.Is(err, os.ErrNotExist) {
-		return nil, nil
+		return sharedConfig{}, nil
 	}
 	if err != nil {
-		return nil, err
+		return sharedConfig{}, err
 	}
 	defer f.Close()
 	raw, err := io.ReadAll(io.LimitReader(f, 65537))
 	if err != nil {
-		return nil, err
+		return sharedConfig{}, err
 	}
 	if len(raw) > 65536 {
-		return nil, errors.New("api: shared root config too large")
+		return sharedConfig{}, errors.New("api: shared root config too large")
 	}
 	var cfg sharedConfig
 	if err = apierrors.DecodeCatalogJSON(raw, &cfg); err != nil {
-		return nil, err
+		return sharedConfig{}, err
 	}
 	if len(cfg.Roots) > 16 {
-		return nil, errors.New("api: at most 16 shared roots")
+		return sharedConfig{}, errors.New("api: at most 16 shared roots")
 	}
 	for name, r := range cfg.Roots {
 		if !lowerName.MatchString(name) || r.Path == "" || len(r.Version) > 128 {
-			return nil, errors.New("api: invalid shared root")
+			return sharedConfig{}, errors.New("api: invalid shared root")
 		}
 		if r.SHA256 != "" && (len(r.SHA256) != 64 || strings.Trim(r.SHA256, "0123456789abcdef") != "") {
-			return nil, errors.New("api: shared sha256 must be 64 lowercase hex characters")
+			return sharedConfig{}, errors.New("api: shared sha256 must be 64 lowercase hex characters")
 		}
 		path := r.Path
 		if !filepath.IsAbs(path) {
@@ -72,22 +73,22 @@ func readSharedRoots(root string) (map[string]SharedRoot, error) {
 		}
 		r.Path, err = filepath.EvalSymlinks(path)
 		if err != nil {
-			return nil, err
+			return sharedConfig{}, err
 		}
 		r.Path, err = filepath.Abs(r.Path)
 		if err != nil {
-			return nil, err
+			return sharedConfig{}, err
 		}
 		stat, err := os.Stat(r.Path)
 		if err != nil {
-			return nil, err
+			return sharedConfig{}, err
 		}
 		if !stat.IsDir() {
-			return nil, errors.New("api: shared root must be a directory")
+			return sharedConfig{}, errors.New("api: shared root must be a directory")
 		}
 		cfg.Roots[name] = r
 	}
-	return cfg.Roots, nil
+	return cfg, nil
 }
 func sourceWithin(root, name string) (string, error) {
 	real, err := filepath.EvalSymlinks(name)
@@ -122,7 +123,7 @@ func sourceMetadata(spec *Spec) map[string]any {
 	return map[string]any{"files": hashes, "shared": shared}
 }
 func sharedSeeds(spec *Spec, directory string) ([]byte, error) {
-	cfg := sharedConfig{Roots: map[string]SharedRoot{}}
+	cfg := sharedConfig{Roots: map[string]SharedRoot{}, Errors: spec.DocumentErrors}
 	for name, r := range spec.SharedRoots {
 		rel, err := filepath.Rel(filepath.Join(directory, "api"), r.Path)
 		if err != nil {
--- a/cmd/go-omni/apigen/templates.go
+++ b/cmd/go-omni/apigen/templates.go
@@ -51,6 +51,19 @@ This project is generated from an editable API contract. Business code uses
 standard context.Context; generated HTTP handlers use Omni's transport-neutral httpx.
 main.go and HTTP composition are continuously generator-owned.

+omni.gen.json selects repository: none (default) or group, and middleware:
+factories for new projects. Named middleware factories run after svc.Init;
+implement Dependencies accessors on ServiceContext and New<Name>(deps) once.
+Unimplemented/nil factories fail startup and clean registered dependencies.
+Existing projects retain middleware: handlers until explicitly migrated.
+Ordinary Logic uses the generated Request/Response types directly. Where an
+independent business type is needed, use ordinary Go or the optional copyx package.
+Configuration loading is generator-managed in internal/config/loadGen.go. Extend fields/defaults/Validate in config.go; additional decoders belong in loader.go/NewLoader. JSON/YAML/XML use one pipeline. See the framework CONFIG.md.
+
+There are no mappings/mappingFiles settings or generated mapping files in v0.19.
+See COPY.md in the framework repository for copy policies and migration steps,
+and GENERATION.md for field composition and middleware factories.
+
 ## Run

 `+"```sh"+`
@@ -133,8 +146,9 @@ internal/svc/runtimeGen.go    # GENERATED lifecycle and infrastructure startup
 internal/apierrors/errorsGen.go # generated fresh error constructors, when declared
 internal/handler/<group>/     # generated binding and Logic adapters
 internal/logic/<group>/      # developer-owned business operations
-internal/repository/<group>/  # developer-owned persistence contracts
-internal/middleware/         # named hooks and generated registry
+internal/repository/<group>/  # optional; repository: group creates editable seeds
+internal/middleware/         # typed dependency interface, factories and registry
+omni.gen.json                # developer-owned repository/middleware options
 docs/openapi.json             # generated OpenAPI 3.0.3
 .goOmni/apiManifest.json      # ownership and content hashes
 `+"```"+`
--- a/cmd/go-omni/apigen/testdata/arrays/consumer_test.go
+++ b/cmd/go-omni/apigen/testdata/arrays/consumer_test.go
@@ -0,0 +1,54 @@
+package main
+
+import (
+	"context"
+	"encoding/json"
+	"example.com/arrays/internal/config"
+	"example.com/arrays/internal/handler"
+	"example.com/arrays/internal/svc"
+	"git.yuntuo.hk/k2safe/go-omni/logx"
+	"io"
+	"net/http/httptest"
+	"strings"
+	"testing"
+)
+
+func TestArrayWire(t *testing.T) {
+	cfg := config.Default()
+	cfg.Server.Log.Writer = io.Discard
+	logger, err := logx.New(cfg.Server.Log)
+	if err != nil {
+		t.Fatal(err)
+	}
+	defer logger.Close()
+	deps, err := svc.New(context.Background(), logger, cfg)
+	if err != nil {
+		t.Fatal(err)
+	}
+	defer deps.Close()
+	app, err := handler.NewApp(deps)
+	if err != nil {
+		t.Fatal(err)
+	}
+	defer app.Close()
+	for path, want := range map[string]string{
+		"/strings": `["企业","备注"]`, "/integers": `[9223372036854775807,-3]`, "/dynamic": `["text",7,true,null,{"name":"企业"},[false,2]]`, "/empty": `[]`, "/raw": `[true,false]`,
+	} {
+		w := httptest.NewRecorder()
+		app.ServeHTTP(w, httptest.NewRequest("GET", path, nil))
+		got := strings.TrimSpace(w.Body.String())
+		if w.Code != 200 {
+			t.Fatal(got)
+		}
+		if path != "/raw" {
+			var obj map[string]json.RawMessage
+			if err := json.Unmarshal(w.Body.Bytes(), &obj); err != nil {
+				t.Fatal(err)
+			}
+			got = string(obj["data"])
+		}
+		if got != want {
+			t.Fatalf("%s got %s want %s", path, got, want)
+		}
+	}
+}
--- a/cmd/go-omni/apigen/testdata/arrays/values.go
+++ b/cmd/go-omni/apigen/testdata/arrays/values.go
@@ -0,0 +1,13 @@
+package arrays
+
+import "context"
+
+func (s *Logic) Strings(context.Context) ([]string, error) { return []string{"企业", "备注"}, nil }
+func (s *Logic) Integers(context.Context) ([]int64, error) {
+	return []int64{9223372036854775807, -3}, nil
+}
+func (s *Logic) Dynamic(context.Context) ([]any, error) {
+	return []any{"text", 7, true, nil, map[string]any{"name": "企业"}, []any{false, 2}}, nil
+}
+func (s *Logic) Empty(context.Context) ([]any, error) { return nil, nil }
+func (s *Logic) Raw(context.Context) ([]bool, error)  { return []bool{true, false}, nil }
--- a/cmd/go-omni/apigen/testdata/composition/accessFactory.go
+++ b/cmd/go-omni/apigen/testdata/composition/accessFactory.go
@@ -0,0 +1,30 @@
+package middleware
+
+import (
+	"errors"
+	"git.yuntuo.hk/k2safe/go-omni/httpx"
+)
+
+var ErrFactory = errors.New("factory fault")
+
+func NewAccess(deps Dependencies) (httpx.Middleware, error) {
+	if deps.Access() == nil {
+		return nil, errors.New("dependencies not initialized")
+	}
+	switch deps.FactoryMode() {
+	case "fail":
+		return nil, ErrFactory
+	case "nil":
+		return nil, nil
+	case "panic":
+		panic(ErrFactory)
+	}
+	return func(next httpx.Handler) httpx.Handler {
+		return func(c *httpx.Context) error {
+			if err := deps.Access().Check(c.Context()); err != nil {
+				return err
+			}
+			return next(c)
+		}
+	}, nil
+}
--- a/cmd/go-omni/apigen/testdata/composition/amount.go
+++ b/cmd/go-omni/apigen/testdata/composition/amount.go
@@ -0,0 +1,52 @@
+package amount
+
+import (
+	"encoding/json"
+	"errors"
+	"fmt"
+	"math/big"
+	"regexp"
+)
+
+// This fixture's business policy is exact decimal HALF_UP. The framework does
+// not choose its precision, rounding mode or currency.
+type Money string
+
+var decimalPattern = regexp.MustCompile(`^-?[0-9]+(\.[0-9]+)?$`)
+
+func (m Money) String() string {
+	if m == "" {
+		return "0.00"
+	}
+	return string(m)
+}
+func (m Money) MarshalJSON() ([]byte, error) { return json.Marshal(m.String()) }
+func (m *Money) UnmarshalJSON(data []byte) error {
+	var text string
+	if err := json.Unmarshal(data, &text); err != nil {
+		return err
+	}
+	if !decimalPattern.MatchString(text) {
+		return errors.New("invalid decimal")
+	}
+	value, ok := new(big.Rat).SetString(text)
+	if !ok {
+		return errors.New("invalid decimal")
+	}
+	value.Mul(value, big.NewRat(100, 1))
+	sign := value.Sign()
+	value.Abs(value)
+	cents, rem := new(big.Int), new(big.Int)
+	cents.QuoRem(value.Num(), value.Denom(), rem)
+	if rem.Mul(rem, big.NewInt(2)).Cmp(value.Denom()) >= 0 {
+		cents.Add(cents, big.NewInt(1))
+	}
+	whole, fraction := new(big.Int), new(big.Int)
+	whole.QuoRem(cents, big.NewInt(100), fraction)
+	prefix := ""
+	if sign < 0 && cents.Sign() != 0 {
+		prefix = "-"
+	}
+	*m = Money(fmt.Sprintf("%s%s.%02d", prefix, whole.String(), fraction.Int64()))
+	return nil
+}
--- a/cmd/go-omni/apigen/testdata/composition/client.go
+++ b/cmd/go-omni/apigen/testdata/composition/client.go
@@ -0,0 +1,36 @@
+package svc
+
+import (
+	"context"
+	"errors"
+	"example.com/composition/internal/middleware"
+	"sync/atomic"
+)
+
+var Closes atomic.Int64
+var ErrInit = errors.New("init fault")
+
+type Client struct{ closed atomic.Bool }
+
+func (c *Client) Check(ctx context.Context) error {
+	if c.closed.Load() {
+		return errors.New("client closed before HTTP drained")
+	}
+	return ctx.Err()
+}
+func (c *ServiceContext) initClient(ctx context.Context) error {
+	c.client = &Client{}
+	c.OnClose(func() error {
+		if !c.client.closed.CompareAndSwap(false, true) {
+			return errors.New("double close")
+		}
+		Closes.Add(1)
+		return nil
+	})
+	if c.Config.FactoryMode == "initFail" {
+		return ErrInit
+	}
+	return nil
+}
+func (c *ServiceContext) Access() middleware.AccessChecker { return c.client }
+func (c *ServiceContext) FactoryMode() string              { return c.Config.FactoryMode }
--- a/cmd/go-omni/apigen/testdata/composition/consumer_test.go
+++ b/cmd/go-omni/apigen/testdata/composition/consumer_test.go
@@ -0,0 +1,217 @@
+package main
+
+import (
+	"context"
+	"encoding/json"
+	"errors"
+	"io"
+	"net"
+	"net/http/httptest"
+	"os"
+	"path/filepath"
+	"strings"
+	"sync"
+	"testing"
+
+	"example.com/composition/internal/amount"
+	"example.com/composition/internal/config"
+	"example.com/composition/internal/convert"
+	"example.com/composition/internal/domain"
+	"example.com/composition/internal/handler"
+	"example.com/composition/internal/middleware"
+	"example.com/composition/internal/svc"
+	"example.com/composition/internal/types"
+	"git.yuntuo.hk/k2safe/go-omni/logx"
+)
+
+func logger(t *testing.T) *logx.Logger {
+	t.Helper()
+	cfg := logx.Default()
+	cfg.Writer = io.Discard
+	l, e := logx.New(cfg)
+	if e != nil {
+		t.Fatal(e)
+	}
+	t.Cleanup(func() { _ = l.Close() })
+	return l
+}
+func TestHTTPComposition(t *testing.T) {
+	deps, e := svc.New(context.Background(), logger(t))
+	if e != nil {
+		t.Fatal(e)
+	}
+	defer deps.Close()
+	app, e := handler.NewApp(deps)
+	if e != nil {
+		t.Fatal(e)
+	}
+	defer app.Close()
+	for _, path := range []string{"/enterprise", "/tenant/123", "/admin/123"} {
+		for _, tc := range []struct {
+			name, body        string
+			status            int
+			salary, nameValue string
+			employer          any
+		}{
+			{"exact", `{"name":"employee","salary":"90071992547409.91","employer":null,"enabled":false}`, 200, "90071992547409.91", "employee", nil},
+			{"round", `{"salary":"1.005","employer":"0"}`, 200, "1.01", "", "0.00"},
+			{"missing", `{}`, 200, "0.00", "", nil},
+			{"null", `{"name":null,"salary":null,"employer":null,"enabled":null}`, 200, "0.00", "", nil},
+			{"zero", `{"salary":"0","enabled":false}`, 200, "0.00", "", nil},
+			{"invalid", `{"salary":"abc"}`, 400, "", "", nil},
+			{"empty", `{"salary":""}`, 400, "", "", nil},
+			{"numeric", `{"salary":100}`, 400, "", "", nil},
+			{"flat", `{"SalaryFields":{"salary":"1"}}`, 400, "", "", nil},
+			{"validation", `{"name":"` + strings.Repeat("x", 81) + `"}`, 400, "", "", nil},
+		} {
+			t.Run(path+tc.name, func(t *testing.T) {
+				req := httptest.NewRequest("POST", path, strings.NewReader(tc.body))
+				req.Header.Set("Content-Type", "application/json")
+				w := httptest.NewRecorder()
+				app.Engine().ServeHTTP(w, req)
+				if w.Code != tc.status {
+					t.Fatalf("status=%d body=%s", w.Code, w.Body.String())
+				}
+				if w.Code == 200 {
+					var out map[string]any
+					if e := json.Unmarshal(w.Body.Bytes(), &out); e != nil {
+						t.Fatal(e)
+					}
+					if out["salary"] != tc.salary || out["employeeName"] != tc.nameValue || out["employer"] != tc.employer || out["id"] != "9007199254740993" {
+						t.Fatal(out)
+					}
+				}
+			})
+		}
+	}
+}
+func TestFullFormAndCopySemantics(t *testing.T) {
+	name := "employee"
+	money := amount.Money("2.00")
+	yes := true
+	req := types.EnterpriseRequest{Name: &name, Salary: &money, Enabled: &yes, Labels: []string{"one"}}
+	first, e := convert.Employee(req)
+	if e != nil {
+		t.Fatal(e)
+	}
+	second, e := convert.Employee(types.EnterpriseRequest{})
+	if e != nil {
+		t.Fatal(e)
+	}
+	if first.EmployeeName != "employee" || !first.Enabled || second.EmployeeName != "" || second.Enabled || second.Salary.String() != "0.00" || second.Employer != nil {
+		t.Fatal("full-form update became patch behavior")
+	}
+	// Direct assignments retain standard Go aliasing, including scalar pointers.
+	first.Labels[0] = "shared"
+	if req.Labels[0] != "shared" {
+		t.Fatal("unexpected implicit deep copy")
+	}
+	req.Employer = &money
+	first, e = convert.Employee(req)
+	if e != nil || first.Employer != req.Employer {
+		t.Fatal("nullable pointer changed", e)
+	}
+	bad := "reject"
+	failed, e := convert.Employee(types.EnterpriseRequest{Name: &bad})
+	if !errors.Is(e, convert.ErrName) || failed.EmployeeName != "" || !strings.Contains(e.Error(), "EmployeeName") {
+		t.Fatal("converter cause/zero result lost", e)
+	}
+	empty, e := convert.ToBatch(domain.Batch{})
+	if e != nil || empty.Rows != nil {
+		t.Fatal("nil slice changed", e)
+	}
+	src := domain.Batch{Rows: []domain.Row{}, Fixed: [2]domain.Row{{Value: "a"}, {Value: "b"}}, Optional: &name}
+	out, e := convert.ToBatch(src)
+	if e != nil || out.Rows == nil || len(out.Rows) != 0 || out.Fixed[1].Value != "b" || out.Optional != src.Optional {
+		t.Fatal(out, e)
+	}
+	src.Rows = []domain.Row{{Value: "one"}}
+	out, e = convert.ToBatch(src)
+	if e != nil || out.Rows[0].Value != "one" {
+		t.Fatal(out, e)
+	}
+	out.Rows[0].Value = "changed"
+	if src.Rows[0].Value != "one" {
+		t.Fatal("element mapping reused input slice")
+	}
+	var wg sync.WaitGroup
+	for i := 0; i < 32; i++ {
+		wg.Add(1)
+		go func() {
+			defer wg.Done()
+			result, err := convert.Employee(types.EnterpriseRequest{Name: &name, Salary: &money})
+			if err != nil || result.EmployeeName != name || result.Salary != money {
+				t.Error(result, err)
+			}
+		}()
+	}
+	wg.Wait()
+}
+func TestFactoryLifecycle(t *testing.T) {
+	for _, mode := range []string{"fail", "nil", "initFail", "panic"} {
+		t.Run(mode, func(t *testing.T) {
+			before := svc.Closes.Load()
+			cfg := config.Default()
+			cfg.FactoryMode = mode
+			if mode == "panic" {
+				func() {
+					defer func() {
+						if recover() != middleware.ErrFactory {
+							t.Error("panic cause changed")
+						}
+					}()
+					_, _ = svc.New(context.Background(), logger(t), cfg)
+				}()
+			} else {
+				deps, err := svc.New(context.Background(), logger(t), cfg)
+				if deps != nil || err == nil {
+					t.Fatal("factory did not fail closed")
+				}
+				if mode == "fail" && !errors.Is(err, middleware.ErrFactory) {
+					t.Fatal("factory cause lost", err)
+				}
+				if mode == "initFail" && !errors.Is(err, svc.ErrInit) {
+					t.Fatal("init cause lost", err)
+				}
+			}
+			if svc.Closes.Load() != before+1 {
+				t.Fatal("dependency not closed exactly once")
+			}
+		})
+	}
+	deps, e := svc.New(context.Background(), logger(t))
+	if e != nil {
+		t.Fatal(e)
+	}
+	if e = deps.Access().Check(context.Background()); e != nil {
+		t.Fatal(e)
+	}
+	before := svc.Closes.Load()
+	if e = deps.Close(); e != nil {
+		t.Fatal(e)
+	}
+	if e = deps.Close(); e != nil {
+		t.Fatal(e)
+	}
+	if svc.Closes.Load() != before+1 {
+		t.Fatal("normal close repeated")
+	}
+}
+func TestGeneratedEntryListenFailure(t *testing.T) {
+	listener, err := net.Listen("tcp", "127.0.0.1:0")
+	if err != nil {
+		t.Fatal(err)
+	}
+	defer listener.Close()
+	path := filepath.Join(t.TempDir(), "config.yaml")
+	if err = os.WriteFile(path, []byte("server:\n  address: "+listener.Addr().String()+"\n"), 0600); err != nil {
+		t.Fatal(err)
+	}
+	before := svc.Closes.Load()
+	if err = run(context.Background(), path); err == nil {
+		t.Fatal("listen should fail")
+	}
+	if svc.Closes.Load() != before+1 {
+		t.Fatal("listen failure did not close dependencies")
+	}
+}
--- a/cmd/go-omni/apigen/testdata/composition/converters.go
+++ b/cmd/go-omni/apigen/testdata/composition/converters.go
@@ -0,0 +1,21 @@
+package convert
+
+import (
+	"errors"
+	"strconv"
+)
+
+var ErrName = errors.New("rejected name")
+
+// Explicit project rules: full-form omission clears strings/bools and uses zero
+// for required money. Nullable employer amounts remain nil by direct assignment.
+func Name(value *string) (string, error) {
+	if value == nil {
+		return "", nil
+	}
+	if *value == "reject" {
+		return "", ErrName
+	}
+	return *value, nil
+}
+func ID(value int64) string { return strconv.FormatInt(value, 10) }
--- a/cmd/go-omni/apigen/testdata/composition/copy.go
+++ b/cmd/go-omni/apigen/testdata/composition/copy.go
@@ -0,0 +1,29 @@
+package convert
+
+import (
+	"example.com/composition/internal/domain"
+	"example.com/composition/internal/types"
+	"git.yuntuo.hk/k2safe/go-omni/copyx"
+)
+
+// The three endpoints reuse one ordinary Go helper and their existing scalar.
+// There is no field list or package/type name JSON to keep in sync.
+func Employee[S any](source S) (domain.Employee, error) {
+	var target domain.Employee
+	err := copyx.Copy(&target, source,
+		copyx.WithFieldNames[S, domain.Employee](map[string]string{"Name": "EmployeeName"}),
+		copyx.WithNilPolicy(copyx.NilZero),
+		copyx.WithConverter(Name),
+	)
+	return target, err
+}
+func Response(source domain.Result) (types.EmployeeResponse, error) {
+	var target types.EmployeeResponse
+	err := copyx.Copy(&target, source, copyx.WithConverter(func(v int64) (string, error) { return ID(v), nil }))
+	return target, err
+}
+func ToBatch(source domain.Batch) (domain.BatchDTO, error) {
+	var target domain.BatchDTO
+	err := copyx.Copy(&target, source)
+	return target, err
+}
--- a/cmd/go-omni/apigen/testdata/composition/dependencies.go
+++ b/cmd/go-omni/apigen/testdata/composition/dependencies.go
@@ -0,0 +1,9 @@
+package middleware
+
+import "context"
+
+type AccessChecker interface{ Check(context.Context) error }
+type Dependencies interface {
+	Access() AccessChecker
+	FactoryMode() string
+}
--- a/cmd/go-omni/apigen/testdata/composition/domain.go
+++ b/cmd/go-omni/apigen/testdata/composition/domain.go
@@ -0,0 +1,29 @@
+package domain
+
+import "example.com/composition/internal/amount"
+
+type Employee struct {
+	EmployeeName string
+	Salary       amount.Money
+	Employer     *amount.Money
+	Enabled      bool
+	Labels       []string
+}
+type Result struct {
+	Employee
+	ID int64
+}
+
+// Distinct container item types exercise explicit Go collection copying.
+type Row struct{ Value string }
+type RowDTO struct{ Value string }
+type Batch struct {
+	Rows     []Row
+	Fixed    [2]Row
+	Optional *string
+}
+type BatchDTO struct {
+	Rows     []RowDTO
+	Fixed    [2]RowDTO
+	Optional *string
+}
--- a/cmd/go-omni/apigen/testdata/composition/service.api
+++ b/cmd/go-omni/apigen/testdata/composition/service.api
@@ -0,0 +1,63 @@
+scalar Money (
+    goImport: "example.com/composition/internal/amount"
+    goType: Money
+    jsonInput: string
+    jsonOutput: string
+)
+
+type SalaryFields {
+    // Employee display name.
+    Name *string `json:"name,optional" binding:"max=80"`
+    Salary *Money `json:"salary,optional"`
+    Employer *Money `json:"employer,optional"`
+    Enabled *bool `json:"enabled,optional"`
+    Labels []string `json:"labels,optional"`
+}
+
+type EnterpriseRequest {
+    SalaryFields
+}
+type TenantRequest {
+    SalaryFields
+    CompanyID string `path:"companyId"`
+}
+type AdminRequest {
+    SalaryFields
+    CompanyID string `path:"companyId"`
+}
+type EmployeeResponse {
+    ID string `json:"id"`
+    EmployeeName string `json:"employeeName"`
+    Salary Money `json:"salary"`
+    Employer *Money `json:"employer"`
+    Enabled bool `json:"enabled"`
+    Labels []string `json:"labels"`
+}
+
+@server (
+    group: enterprise
+    middleware: Access
+    response: raw
+)
+service composition {
+    @handler save
+    post /enterprise (EnterpriseRequest) returns (EmployeeResponse)
+}
+@server (
+    group: tenant
+    middleware: Access
+    response: raw
+)
+service composition {
+    @handler save
+    post /tenant/:companyId (TenantRequest) returns (EmployeeResponse)
+}
+@server (
+    group: admin
+    middleware: Access
+    response: raw
+)
+service composition {
+    @handler save
+    post /admin/:companyId (AdminRequest) returns (EmployeeResponse)
+}
--- a/cmd/go-omni/apigen/testdata/configuration/consumer_test.go
+++ b/cmd/go-omni/apigen/testdata/configuration/consumer_test.go
@@ -0,0 +1,59 @@
+package main
+
+import (
+	"context"
+	"errors"
+	"example.com/configuration/internal/config"
+	omniConfig "git.yuntuo.hk/k2safe/go-omni/config"
+	"os"
+	"path/filepath"
+	"strings"
+	"testing"
+)
+
+func TestGeneratedConfiguration(t *testing.T) {
+	for ext, source := range map[string]string{
+		"json": `{"limit":7}`, "yaml": "limit: 7\n", "xml": "<config><limit>7</limit></config>", "custom": `{"limit":7}`,
+	} {
+		t.Run(ext, func(t *testing.T) {
+			path := filepath.Join(t.TempDir(), "app."+ext)
+			if err := os.WriteFile(path, []byte(source), 0600); err != nil {
+				t.Fatal(err)
+			}
+			cfg, err := config.Load(path)
+			if err != nil {
+				t.Fatal(err)
+			}
+			if cfg.Limit != 7 {
+				t.Fatal(cfg.Limit)
+			}
+			t.Setenv("GO_OMNI_LIMIT", "0")
+			cfg, err = config.Load(path)
+			if err != nil || cfg.Limit != 0 {
+				t.Fatal(cfg.Limit, err)
+			}
+		})
+	}
+	t.Setenv("GO_OMNI_LOG_OUTPUT", "stderr")
+	cfg, err := config.Load("")
+	if err != nil {
+		t.Fatal(err)
+	}
+	if cfg.Limit != 10 || cfg.Server.Log.File != "" || cfg.Server.Log.Rotation.Enabled {
+		t.Fatal("defaults/log normalization", cfg, err)
+	}
+	path := filepath.Join(t.TempDir(), "bad.yaml")
+	os.WriteFile(path, []byte("limit: -1\n"), 0600)
+	// Validation must run before svc.Initialize; the project initializer panics
+	// below if reached, so this also detects accidentally starting dependencies.
+	err = run(context.Background(), path)
+	var diagnostic *omniConfig.Error
+	if !errors.As(err, &diagnostic) || diagnostic.Field != "limit" || diagnostic.File != path || diagnostic.Line != 1 {
+		t.Fatal(err)
+	}
+	t.Setenv("GO_OMNI_LIMIT", "private-not-a-number")
+	_, err = config.Load(path)
+	if !errors.As(err, &diagnostic) || diagnostic.Env != "GO_OMNI_LIMIT" || strings.Contains(err.Error(), "private-not-a-number") {
+		t.Fatal(err)
+	}
+}
--- a/cmd/go-omni/apigen/upgrade.go
+++ b/cmd/go-omni/apigen/upgrade.go
@@ -30,6 +30,39 @@ type UpgradePlan struct {
 	Module, Entry string
 }

+// Handwritten old loaders must be migrated explicitly, never silently replaced
+// or left competing with the generated entry point.
+func checkConfigLoadExtension(root string) error {
+	dir := filepath.Join(root, "internal/config")
+	entries, err := os.ReadDir(dir)
+	if errors.Is(err, os.ErrNotExist) {
+		return nil
+	}
+	if err != nil {
+		return err
+	}
+	for _, entry := range entries {
+		name := entry.Name()
+		if entry.IsDir() || !strings.HasSuffix(name, ".go") || strings.HasSuffix(name, "_test.go") || name == "loadGen.go" {
+			continue
+		}
+		rel := "internal/config/" + name
+		if err := safePath(root, rel); err != nil {
+			return err
+		}
+		f, err := goparser.ParseFile(gotoken.NewFileSet(), filepath.Join(root, rel), nil, 0)
+		if err != nil {
+			return fmt.Errorf("parse %s: %w", rel, err)
+		}
+		for _, decl := range f.Decls {
+			if fn, ok := decl.(*ast.FuncDecl); ok && fn.Recv == nil && fn.Name.Name == "Load" {
+				return fmt.Errorf("%s: migrate the project-owned Load function before generating internal/config/loadGen.go; retain Config/Default/Validate and move decoder options to NewLoader; see CONFIG.md", rel)
+			}
+		}
+	}
+	return nil
+}
+
 // PlanUpgrade compares infrastructure against the exact previous release seeds.
 // A custom file is never classified as safe to replace. Logic, middleware,
 // options and repositories outside the changed templates are left untouched.
--- a/cmd/go-omni/apigen/upgrade_test.go
+++ b/cmd/go-omni/apigen/upgrade_test.go
@@ -39,7 +39,7 @@ func oldInfrastructureProject(t *testing.T) string {
 	raw, _ := json.Marshal(m)
 	writeFile(t, filepath.Join(dir, manifestPath), string(raw))
 	path := filepath.Join(dir, "go.mod")
-	writeFile(t, path, strings.ReplaceAll(readFile(t, path), minimumVersion, "v0.13.0-preview"))
+	writeFile(t, path, strings.ReplaceAll(readFile(t, path), currentVersion, "v0.13.0-preview"))
 	return dir
 }

@@ -74,7 +74,7 @@ func TestUpgradeV014PreservesExtensions(t *testing.T) {
 	raw, _ := json.Marshal(m)
 	writeFile(t, filepath.Join(dir, manifestPath), string(raw))
 	mod := filepath.Join(dir, "go.mod")
-	writeFile(t, mod, strings.ReplaceAll(readFile(t, mod), minimumVersion, "v0.14.1-preview"))
+	writeFile(t, mod, strings.ReplaceAll(readFile(t, mod), currentVersion, "v0.14.1-preview"))
 	owned := map[string]string{}
 	for _, name := range []string{"internal/svc/serviceContext.go", "internal/config/config.go", "etc/config.yaml"} {
 		path := filepath.Join(dir, name)
--- a/cmd/go-omni/apigen/workspace.go
+++ b/cmd/go-omni/apigen/workspace.go
@@ -16,7 +16,8 @@ type WorkspaceService struct {
 	Module string `json:"module,omitempty"`
 }
 type WorkspaceConfig struct {
-	Services []WorkspaceService `json:"services"`
+	Services      []WorkspaceService `json:"services"`
+	ErrorCatalogs []WorkspaceCatalog `json:"errorCatalogs,omitempty"`
 }

 // Workspace operates independent Go modules listed in an explicit local file.
@@ -83,6 +84,16 @@ func Workspace(path, command string, w io.Writer) error {
 		}
 		options = append(options, Options{API: entry, Dir: dir, Module: service.Module, DryRun: true})
 	}
+	var catalogs map[string][]byte
+	if command != "format" {
+		catalogs, err = prepareWorkspaceCatalogs(root, cfg.ErrorCatalogs, command == "check")
+		if err != nil {
+			return err
+		}
+		for i := range options {
+			options[i].documentCatalogs = catalogs
+		}
+	}
 	var failures error
 	for _, o := range options {
 		if command == "format" {
@@ -101,6 +112,13 @@ func Workspace(path, command string, w io.Writer) error {
 	if failures != nil {
 		return failures
 	}
+	if command == "generate" {
+		for path, data := range catalogs {
+			if err = writeWorkspaceCatalog(path, data); err != nil {
+				return err
+			}
+		}
+	}
 	for _, o := range options {
 		switch command {
 		case "format":
--- a/cmd/go-omni/apigen/workspaceCatalog.go
+++ b/cmd/go-omni/apigen/workspaceCatalog.go
@@ -0,0 +1,217 @@
+package apigen
+
+import (
+	"bytes"
+	"context"
+	"encoding/json"
+	"errors"
+	"fmt"
+	gotoken "go/token"
+	"io"
+	"os"
+	"os/exec"
+	"path/filepath"
+	"strings"
+	"time"
+
+	apierrors "git.yuntuo.hk/k2safe/go-omni/errors"
+	"golang.org/x/mod/modfile"
+	"golang.org/x/mod/module"
+)
+
+// WorkspaceCatalog is an explicitly trusted Go provider: func() errors.Catalog.
+// Only workspace generate/check execute providers. Parsing an .api never does.
+type WorkspaceCatalog struct {
+	Dir      string `json:"dir"`
+	Package  string `json:"package"`
+	Function string `json:"function"`
+	Output   string `json:"output"`
+}
+
+type limitedCatalogBuffer struct {
+	bytes.Buffer
+	limit int
+}
+
+func (b *limitedCatalogBuffer) Write(p []byte) (int, error) {
+	if len(p) > b.limit-b.Len() {
+		return 0, errors.New("catalog provider output exceeds limit")
+	}
+	return b.Buffer.Write(p)
+}
+
+func exportWorkspaceCatalog(root string, cfg WorkspaceCatalog) ([]byte, error) {
+	if cfg.Dir == "" || cfg.Output == "" || !gotoken.IsIdentifier(cfg.Function) || !gotoken.IsExported(cfg.Function) || module.CheckImportPath(cfg.Package) != nil {
+		return nil, errors.New("workspace catalog requires dir, an importable package, an exported function and output")
+	}
+	if err := safePath(root, filepath.ToSlash(filepath.Join(cfg.Dir, ".goOmniExportCheck"))); err != nil {
+		return nil, err
+	}
+	if err := safePath(root, cfg.Output); err != nil {
+		return nil, err
+	}
+	if filepath.Ext(cfg.Output) != ".json" {
+		return nil, errors.New("workspace catalog output must be .json")
+	}
+	dir := filepath.Join(root, filepath.FromSlash(cfg.Dir))
+	if stat, err := os.Stat(filepath.Join(dir, "go.mod")); err != nil || !stat.Mode().IsRegular() {
+		return nil, errors.New("workspace catalog dir must contain go.mod")
+	}
+	temp, err := os.MkdirTemp("", "go-omni-catalog-*")
+	if err != nil {
+		return nil, err
+	}
+	defer os.RemoveAll(temp)
+	// Overlay a virtual Go file under the provider module. This allows internal
+	// packages without creating files or changing go.mod/go.sum in that module.
+	virtual := filepath.Join(dir, ".goOmniCatalogExport", "main.go")
+	if _, err := os.Lstat(filepath.Dir(virtual)); !errors.Is(err, os.ErrNotExist) {
+		return nil, errors.New("reserved catalog export path already exists")
+	}
+	source := fmt.Sprintf("package main\nimport (\"os\"; provider %q; omnierrors %q)\nfunc main(){if err:=omnierrors.ExportCatalog(os.Stdout,provider.%s());err!=nil{os.Exit(1)}}\n", cfg.Package, frameworkModule+"/errors", cfg.Function)
+	backing := filepath.Join(temp, "main.go")
+	if err = os.WriteFile(backing, []byte(source), 0600); err != nil {
+		return nil, err
+	}
+	overlay, _ := json.Marshal(map[string]any{"Replace": map[string]string{virtual: backing}})
+	overlayPath := filepath.Join(temp, "overlay.json")
+	if err = os.WriteFile(overlayPath, overlay, 0600); err != nil {
+		return nil, err
+	}
+	// Keep all module metadata writes in the temporary directory as well.
+	// -mod=readonly alone must not be relied on to protect every go.sum update.
+	moduleData, err := os.ReadFile(filepath.Join(dir, "go.mod"))
+	if err != nil {
+		return nil, err
+	}
+	mf, err := modfile.Parse("go.mod", moduleData, nil)
+	if err != nil {
+		return nil, errors.New("workspace catalog has invalid go.mod")
+	}
+	replacements := append([]*modfile.Replace(nil), mf.Replace...)
+	for _, r := range replacements {
+		if r.New.Version == "" && !filepath.IsAbs(r.New.Path) {
+			if err = mf.AddReplace(r.Old.Path, r.Old.Version, filepath.Join(dir, r.New.Path), ""); err != nil {
+				return nil, err
+			}
+		}
+	}
+	moduleData, err = mf.Format()
+	if err != nil {
+		return nil, err
+	}
+	modPath := filepath.Join(temp, "go.mod")
+	if err = os.WriteFile(modPath, moduleData, 0600); err != nil {
+		return nil, err
+	}
+	if sums, e := os.ReadFile(filepath.Join(dir, "go.sum")); e == nil {
+		if err = os.WriteFile(filepath.Join(temp, "go.sum"), sums, 0600); err != nil {
+			return nil, err
+		}
+	} else if !errors.Is(e, os.ErrNotExist) {
+		return nil, e
+	}
+	ctx, cancel := context.WithTimeout(context.Background(), 90*time.Second)
+	defer cancel()
+
+	executable := filepath.Join(temp, "catalogExport")
+	// Build first, then execute the binary directly: cancellation kills the
+	// provider itself instead of only terminating a go-run wrapper process.
+	build := exec.CommandContext(ctx, "go", "build", "-mod=readonly", "-modfile", modPath, "-overlay", overlayPath, "-o", executable, virtual)
+	build.Dir = dir
+	build.Env = append(os.Environ(), "GOWORK=off")
+	build.WaitDelay = 2 * time.Second
+	build.Stdout = &limitedCatalogBuffer{limit: 64 << 10}
+	build.Stderr = &limitedCatalogBuffer{limit: 64 << 10}
+	if err = build.Run(); err != nil {
+		return nil, fmt.Errorf("workspace catalog %s.%s: build failed (%v); check module dependencies and func() errors.Catalog signature", cfg.Package, cfg.Function, err)
+	}
+	cmd := exec.CommandContext(ctx, executable)
+	cmd.Dir = dir
+	cmd.Env = append(os.Environ(), "GOWORK=off")
+	cmd.WaitDelay = 2 * time.Second
+	stdout := &limitedCatalogBuffer{limit: 1 << 20}
+	stderr := &limitedCatalogBuffer{limit: 64 << 10}
+	cmd.Stdout = stdout
+	cmd.Stderr = stderr
+	if err = cmd.Run(); err != nil {
+		if ctx.Err() != nil {
+			return nil, fmt.Errorf("workspace catalog %s: %w", cfg.Package, ctx.Err())
+		}
+		// Provider output can contain arbitrary application data. Do not echo it.
+		return nil, fmt.Errorf("workspace catalog %s.%s: execution failed (%v); provider must return errors.Catalog without writing stdout", cfg.Package, cfg.Function, err)
+	}
+	var catalog apierrors.Catalog
+	if err = apierrors.DecodeCatalogJSON(stdout.Bytes(), &catalog); err != nil {
+		return nil, errors.New("workspace catalog provider did not emit a valid catalog")
+	}
+	var normalized bytes.Buffer
+	if err = apierrors.ExportCatalog(&normalized, catalog); err != nil {
+		return nil, err
+	}
+	return normalized.Bytes(), nil
+}
+
+func prepareWorkspaceCatalogs(root string, configs []WorkspaceCatalog, check bool) (map[string][]byte, error) {
+	if len(configs) > 16 {
+		return nil, errors.New("workspace supports at most 16 catalog providers")
+	}
+	result := map[string][]byte{}
+	for _, cfg := range configs {
+		if err := safePath(root, cfg.Output); err != nil {
+			return nil, err
+		}
+		path := filepath.Join(root, filepath.FromSlash(cfg.Output))
+		for prior := range result {
+			if strings.EqualFold(prior, path) {
+				return nil, errors.New("workspace catalog outputs overlap")
+			}
+		}
+		data, err := exportWorkspaceCatalog(root, cfg)
+		if err != nil {
+			return nil, err
+		}
+		if check {
+			old, err := os.ReadFile(path)
+			if err != nil || !bytes.Equal(old, data) {
+				return nil, fmt.Errorf("workspace catalog drift: %s; run workspace generate", cfg.Output)
+			}
+		}
+		result[path] = data
+	}
+	return result, nil
+}
+
+func writeWorkspaceCatalog(path string, data []byte) error {
+	mode := os.FileMode(0644)
+	if stat, err := os.Lstat(path); err == nil {
+		if !stat.Mode().IsRegular() {
+			return errors.New("workspace catalog output must be a regular file")
+		}
+		mode = stat.Mode().Perm()
+	} else if !errors.Is(err, os.ErrNotExist) {
+		return err
+	}
+	old, err := os.ReadFile(path)
+	if err == nil && bytes.Equal(old, data) {
+		return nil
+	}
+	if err != nil && !errors.Is(err, os.ErrNotExist) {
+		return err
+	}
+	f, err := os.CreateTemp(filepath.Dir(path), ".omni-catalog-*")
+	if err != nil {
+		return err
+	}
+	defer os.Remove(f.Name())
+	if err = f.Chmod(mode); err != nil {
+		_ = f.Close()
+		return err
+	}
+	_, writeErr := io.Copy(f, bytes.NewReader(data))
+	err = errors.Join(writeErr, f.Close())
+	if err != nil {
+		return err
+	}
+	return os.Rename(f.Name(), path)
+}
--- a/cmd/go-omni/apigen/workspaceCatalog_test.go
+++ b/cmd/go-omni/apigen/workspaceCatalog_test.go
@@ -0,0 +1,168 @@
+package apigen
+
+import (
+	"bytes"
+	"encoding/json"
+	"fmt"
+	"io"
+	"os"
+	"path/filepath"
+	"strings"
+	"testing"
+)
+
+func TestWorkspaceSharedGoCatalog(t *testing.T) {
+	root := t.TempDir()
+	writeFile(t, filepath.Join(root, "go.mod"), fmt.Sprintf("module example.com/catalogs\n\ngo 1.24.0\nrequire %s v0.15.0-preview\nreplace %s => %s\n", frameworkModule, frameworkModule, strconvQuote(frameworkRoot(t))))
+	writeFile(t, filepath.Join(root, "internal/apierrors/catalog.go"), `package apierrors
+import errors "git.yuntuo.hk/k2safe/go-omni/errors"
+func Catalog() errors.Catalog {return errors.Catalog{DefaultStatus:400,Definitions:map[string]errors.Definition{
+"INVALID":{Code:"INVALID",Message:"invalid input"},"MISSING":{Status:404,Code:"MISSING",Message:"missing"},
+}}}
+`)
+	if err := os.MkdirAll(filepath.Join(root, "contracts"), 0755); err != nil {
+		t.Fatal(err)
+	}
+	for _, name := range []string{"api", "id"} {
+		dir := filepath.Join(root, "services", name)
+		if _, err := New(Options{Dir: dir, Module: "example.com/" + name, FrameworkDir: frameworkRoot(t)}); err != nil {
+			t.Fatal(err)
+		}
+		writeFile(t, filepath.Join(dir, "api/omni.imports.json"), `{"roots":{"common":{"path":"../../../contracts"}},"errors":{"source":"@common/errors.json","include":["INVALID"],"routes":{"GET /api/greet/:name":["MISSING"]}}}`)
+	}
+	workspace := filepath.Join(root, "omni.workspace.json")
+	writeFile(t, workspace, `{"errorCatalogs":[{"dir":".","package":"example.com/catalogs/internal/apierrors","function":"Catalog","output":"contracts/errors.json"}],"services":[{"dir":"services/api"},{"dir":"services/id"}]}`)
+	if err := Workspace(workspace, "generate", io.Discard); err != nil {
+		t.Fatal(err)
+	}
+	if err := Workspace(workspace, "format", io.Discard); err != nil {
+		t.Fatal(err)
+	}
+	if err := Workspace(workspace, "generate", io.Discard); err != nil {
+		t.Fatal(err)
+	}
+	before := snapshot(t, root)
+	if err := Workspace(workspace, "check", io.Discard); err != nil {
+		t.Fatal(err)
+	}
+	if !sameFiles(before, snapshot(t, root)) {
+		t.Fatal("check wrote project files")
+	}
+	for _, name := range []string{"api", "id"} {
+		entry := filepath.Join(root, "services", name, "api/service.api")
+		spec, err := Parse(entry)
+		if err != nil {
+			t.Fatal(err)
+		}
+		c, err := Compile(spec)
+		if err != nil {
+			t.Fatal(err)
+		}
+		op := operation(t, document(t, c), "/api/greet/{name}", "get")
+		if op["responses"].(map[string]any)["404"] == nil || len(spec.Errors) != 0 || len(spec.Routes[0].Errors) != 0 {
+			t.Fatal("selection changed runtime catalog")
+		}
+		if _, err = os.Stat(filepath.Join(filepath.Dir(entry), catalogDocumentFile)); !os.IsNotExist(err) {
+			t.Fatal("shared catalog was copied")
+		}
+	}
+	shared := filepath.Join(root, "contracts/errors.json")
+	data := readFile(t, shared)
+	writeFile(t, shared, strings.Replace(data, "invalid input", "stale", 1))
+	before = snapshot(t, root)
+	if err := Workspace(workspace, "check", io.Discard); err == nil || !strings.Contains(err.Error(), "catalog drift") {
+		t.Fatal(err)
+	}
+	if !sameFiles(before, snapshot(t, root)) {
+		t.Fatal("drift check wrote files")
+	}
+	if err := Workspace(workspace, "generate", io.Discard); err != nil {
+		t.Fatal(err)
+	}
+	if got := readFile(t, shared); got != data {
+		t.Fatal("catalog not refreshed")
+	}
+	// Failed provider/preflight may not update even the shared metadata.
+	source := filepath.Join(root, "internal/apierrors/catalog.go")
+	writeFile(t, source, readFile(t, source)+"\ninvalid go source")
+	before = snapshot(t, root)
+	if err := Workspace(workspace, "generate", io.Discard); err == nil {
+		t.Fatal("provider failure ignored")
+	}
+	if !sameFiles(before, snapshot(t, root)) {
+		t.Fatal("provider failure mutated project")
+	}
+}
+
+func TestDocumentSelectionBoundaries(t *testing.T) {
+	root := t.TempDir()
+	local := filepath.Join(root, "api")
+	shared := filepath.Join(root, "shared")
+	entry := filepath.Join(local, "service.api")
+	writeFile(t, entry, "service demo {\n@handler list\nget /list returns ([]string)\n}\n")
+	writeFile(t, filepath.Join(shared, "errors.json"), `{"defaultStatus":400,"definitions":{"INVALID":{"code":400002,"message":"invalid"}}}`)
+	for _, cfg := range []string{
+		`{"source":"@common/errors.json","include":["UNKNOWN"]}`,
+		`{"source":"@common/errors.json","routes":{"GET /absent":["INVALID"]}}`,
+		`{"source":"@common/../api/service.api"}`,
+		`{"source":"../shared/errors.json"}`,
+	} {
+		writeFile(t, filepath.Join(local, importsFile), `{"roots":{"common":{"path":"../shared"}},"errors":`+cfg+`}`)
+		if _, err := Parse(entry); err == nil {
+			t.Fatal("bad selection accepted", cfg)
+		}
+	}
+	writeFile(t, filepath.Join(local, importsFile), `{"roots":{"common":{"path":"../shared"}},"errors":{"source":"@common/errors.json","include":[]}}`)
+	spec, err := Parse(entry)
+	if err != nil {
+		t.Fatal(err)
+	}
+	if len(documentRouteCatalog(spec, spec.Routes[0]).Definitions) != 0 {
+		t.Fatal("empty include ignored")
+	}
+	seeded, err := sharedSeeds(spec, filepath.Join(root, "generated"))
+	if err != nil {
+		t.Fatal(err)
+	}
+	var cfg sharedConfig
+	if err = json.Unmarshal(seeded, &cfg); err != nil {
+		t.Fatal(err)
+	}
+	if cfg.Errors.Include == nil || !bytes.Contains(seeded, []byte(`"include": []`)) {
+		t.Fatal("empty selection lost during relocation")
+	}
+}
+
+func TestWorkspaceCatalogPathsAndProviderValidation(t *testing.T) {
+	root := t.TempDir()
+	writeFile(t, filepath.Join(root, "go.mod"), "module example.com/test\ngo 1.24.0\n")
+	good := WorkspaceCatalog{Dir: ".", Package: "example.com/test/internal/errors", Function: "Catalog", Output: "errors.json"}
+	cases := []WorkspaceCatalog{}
+	for _, change := range []func(*WorkspaceCatalog){
+		func(c *WorkspaceCatalog) { c.Dir = "../outside" },
+		func(c *WorkspaceCatalog) { c.Output = "../outside.json" },
+		func(c *WorkspaceCatalog) { c.Package = "example.com/pkg;bad" },
+		func(c *WorkspaceCatalog) { c.Function = "Catalog()" },
+		func(c *WorkspaceCatalog) { c.Output = "go.mod" },
+	} {
+		c := good
+		change(&c)
+		cases = append(cases, c)
+	}
+	for _, c := range cases {
+		if _, err := exportWorkspaceCatalog(root, c); err == nil {
+			t.Fatal("bad provider accepted", c)
+		}
+	}
+	outside := filepath.Join(t.TempDir(), "errors.json")
+	writeFile(t, outside, `{}`)
+	if err := os.Symlink(outside, filepath.Join(root, "errors.json")); err != nil {
+		t.Fatal(err)
+	}
+	if _, err := prepareWorkspaceCatalogs(root, []WorkspaceCatalog{good}, false); err == nil {
+		t.Fatal("symlink output accepted")
+	}
+	if readFile(t, outside) != `{}` {
+		t.Fatal("outside file modified")
+	}
+}
--- a/cmd/go-omni/apigen/write.go
+++ b/cmd/go-omni/apigen/write.go
@@ -16,6 +16,7 @@ import (
 const manifestPath = ".goOmni/apiManifest.json"

 type manifest struct {
+	GeneratorConfig bool              `json:"generatorConfig,omitempty"`
 	TemplateVersion string            `json:"templateVersion,omitempty"`
 	Profile         *projectProfile   `json:"profile,omitempty"`
 	Version         int               `json:"version"`
@@ -109,13 +110,24 @@ func apply(root, module, entry string, generated, seeds map[string][]byte, check
 			return result, err
 		}
 	}
-	next := manifest{TemplateVersion: minimumVersion, Profile: &profile, Version: 2, Module: module, Entry: entry, Generated: map[string]string{}, Contract: contract}
+	next := manifest{GeneratorConfig: true, TemplateVersion: minimumVersion, Profile: &profile, Version: 2, Module: module, Entry: entry, Generated: map[string]string{}, Contract: contract}
 	for name, data := range generated {
 		next.Generated[name] = digest(data)
 	}
 	var changes []change
 	// Check ALL previous outputs, even stale ones, before writing any new file.
 	for name, hash := range old.Generated {
+		// Migration guard only; old mappings are never regenerated or silently
+		// deleted. Once the project removes them, forget the stale ownership.
+		if name == "internal/mapping/mappingsGen.go" {
+			if err = safePath(root, name); err != nil {
+				return result, err
+			}
+			if _, e := os.Lstat(filepath.Join(root, name)); !errors.Is(e, os.ErrNotExist) {
+				return result, errors.New("mapping generation was removed: migrate callers to copyx or ordinary Go and remove internal/mapping/mappingsGen.go before generating; see COPY.md")
+			}
+			continue
+		}
 		if !ownedPath(name) {
 			return result, fmt.Errorf("api: invalid owned path %q", name)
 		}
@@ -272,6 +284,9 @@ func apply(root, module, entry string, generated, seeds map[string][]byte, check
 }
 func digest(data []byte) string { sum := sha256.Sum256(data); return hex.EncodeToString(sum[:]) }
 func ownedPath(name string) bool {
+	if name == "internal/config/loadGen.go" {
+		return true
+	}
 	if strings.HasPrefix(name, "internal/types/dto") && strings.HasSuffix(name, "Gen.go") && goName.MatchString(strings.TrimSuffix(filepath.Base(name), ".go")) {
 		return true
 	}
--- a/cmd/go-omni/main_test.go
+++ b/cmd/go-omni/main_test.go
@@ -8,7 +8,7 @@ import (
 )

 func TestNewWithRemoteFrameworkVersion(t *testing.T) {
-	for _, flag := range [][]string{{"--framework-version", "v0.15.0-preview"}, {"--framework-version=v0.15.0-preview"}} {
+	for _, flag := range [][]string{{"--framework-version", "v0.21.0-preview"}, {"--framework-version=v0.21.0-preview"}} {
 		project := filepath.Join(t.TempDir(), "billing")
 		args := append([]string{"--module", "example.com/billing"}, flag...)
 		if err := runNew(append(args, project)); err != nil {
@@ -18,7 +18,7 @@ func TestNewWithRemoteFrameworkVersion(t *testing.T) {
 		if err != nil {
 			t.Fatal(err)
 		}
-		if !strings.Contains(string(content), "go-omni v0.15.0-preview") || strings.Contains(string(content), "replace ") {
+		if !strings.Contains(string(content), "go-omni v0.21.0-preview") || strings.Contains(string(content), "replace ") {
 			t.Fatalf("CLI did not pin remote dependency: %s", content)
 		}
 	}
--- a/cmd/go-omni/scaffold/apiInfrastructure.go
+++ b/cmd/go-omni/scaffold/apiInfrastructure.go
@@ -21,6 +21,8 @@ func apiInfrastructure(module, database, storage, logOutput, logFormat string, l
 		"internal/svc/runtimeGen.go":     "templates/api-runtime.go.tmpl",
 		"internal/svc/options.go":        "templates/api-options.go.tmpl",
 		"internal/config/config.go":      "templates/api-config.go.tmpl",
+		"internal/config/loadGen.go":     "templates/api-load.go.tmpl",
+		"internal/config/loader.go":      "templates/api-loader.go.tmpl",
 		"etc/config.yaml":                "templates/modules-config.yaml.tmpl",
 		"internal/svc/serviceContext.go": "templates/api-context.go.tmpl",
 	}
@@ -31,6 +33,8 @@ func apiInfrastructure(module, database, storage, logOutput, logFormat string, l
 		files["internal/svc/storage.go"] = "templates/modules-storage.go.tmpl"
 	}
 	if legacy {
+		delete(files, "internal/config/loadGen.go")
+		delete(files, "internal/config/loader.go")
 		delete(files, "internal/svc/runtimeGen.go")
 		delete(files, "internal/svc/databaseOptions.go")
 		files["internal/svc/close.go"] = "templates/api-close.go.tmpl"
--- a/cmd/go-omni/scaffold/templates/api-config.go.tmpl
+++ b/cmd/go-omni/scaffold/templates/api-config.go.tmpl
@@ -1,10 +1,9 @@
 package settings
 import (
- "os"
- "strings"
+ {{if and (not .API) (ne .Storage "none")}}"strings"{{end}}
 "time"
 "git.yuntuo.hk/k2safe/go-omni/config"
- "git.yuntuo.hk/k2safe/go-omni/logx"
+ {{if eq .LogOutput "file"}}"git.yuntuo.hk/k2safe/go-omni/logx"{{end}}
 {{if eq .Database "mysql"}}mysqladapter "git.yuntuo.hk/k2safe/go-omni/database/mysql"{{end}}
 {{if ne .Storage "none"}}"errors"
 {{if ne .Storage "r2"}}"net/url"{{else}}"regexp"{{end}}
@@ -35,22 +34,10 @@ func Default() Config {
 }{{end}}}
 }

-// Load applies defaults -> file -> typed environment -> validation.
-// New fields automatically use GO_OMNI_<JSON_PATH>, or an explicit env tag.
-func Load(path string)(Config,error){
- cfg:=Default();var err error
- cfg,err=config.ApplyDefaults(cfg);if err!=nil{return Config{},err}
- if path!="" {cfg,err=config.DecodeFile(path,cfg);if err!=nil{return Config{},err}}
- cfg,err=config.OverlayEnv(cfg,config.EnvOptions{Prefix:"GO_OMNI_"});if err!=nil{return Config{},err}
- // Preserve the documented framework aliases (HTTP_ADDR, LOG_LEVEL, etc).
- cfg.Server,err=config.ApplyEnv(cfg.Server,"");if err!=nil{return Config{},err}
- if output:=strings.TrimSpace(os.Getenv("GO_OMNI_LOG_OUTPUT"));output!="" && strings.TrimSpace(os.Getenv("GO_OMNI_LOG_FILE"))=="" {cfg.Server.Log.File="";cfg.Server.Log.Rotation=logx.RotationConfig{}}
- return cfg,cfg.Validate()
-}
 func(c Config)Validate()error{
- if err:=c.Server.Validate();err!=nil{return err}
- {{if eq .Database "mysql"}}if err:=c.Database.Validate();err!=nil{return err}{{end}}
- {{if ne .Storage "none"}}if err:=c.Storage.Validate();err!=nil{return err}{{end}}
+ if err:=c.Server.Validate();err!=nil{return config.AtField("server",err)}
+ {{if eq .Database "mysql"}}if err:=c.Database.Validate();err!=nil{return config.AtField("database",err)}{{end}}
+ {{if ne .Storage "none"}}if err:=c.Storage.Validate();err!=nil{return config.AtField("storage",err)}{{end}}
 return nil
 }
 {{if ne .Storage "none"}}
--- a/cmd/go-omni/scaffold/templates/api-load.go.tmpl
+++ b/cmd/go-omni/scaffold/templates/api-load.go.tmpl
@@ -0,0 +1,13 @@
+package config
+
+import omniConfig "git.yuntuo.hk/k2safe/go-omni/config"
+
+// Load is maintained by the generator. Extend Config/Default/Validate in
+// config.go, or NewLoader in loader.go; do not duplicate the loading pipeline.
+func Load(path string) (Config, error) {
+ loader,err:=NewLoader()
+ if err!=nil{return Config{},err}
+ return omniConfig.LoadProject(path,Default(),omniConfig.EnvOptions{
+  Prefix:"GO_OMNI_",Empty:"ignore",Aliases:omniConfig.ServerEnvAliases("GO_OMNI_","server"),
+ },loader)
+}
--- a/cmd/go-omni/scaffold/templates/api-loader.go.tmpl
+++ b/cmd/go-omni/scaffold/templates/api-loader.go.tmpl
@@ -0,0 +1,7 @@
+package config
+
+import omniConfig "git.yuntuo.hk/k2safe/go-omni/config"
+
+// NewLoader is project-owned. JSON/YAML/XML work without changes. Register
+// additional format decoders here only when the project needs them.
+func NewLoader() (*omniConfig.Loader,error) { return omniConfig.NewLoader() }
--- a/cmd/go-omni/scaffold/version.go
+++ b/cmd/go-omni/scaffold/version.go
@@ -10,7 +10,7 @@ const frameworkModule = "git.yuntuo.hk/k2safe/go-omni"
 // Source builds can carry an unpublished VCS version (including +dirty).
 // Keep this fallback in sync with the next release; installed CLIs use their
 // downloaded module version, which also has a module checksum.
-const defaultFrameworkVersion = "v0.15.0-preview"
+const defaultFrameworkVersion = "v0.21.0-preview"

 // This target is not a claim that the release already exists. Source users
 // select a local framework checkout until the module templates are published.
--- a/config/aliases_test.go
+++ b/config/aliases_test.go
@@ -0,0 +1,66 @@
+package config
+
+import (
+	"strings"
+	"testing"
+	"time"
+)
+
+func TestUnifiedEnvAliases(t *testing.T) {
+	type project struct {
+		Server Config `json:"server"`
+		Label  string `json:"label"`
+	}
+	base := project{Server: Default(), Label: "base"}
+	for _, policy := range []string{"allow", "ignore", "reject"} {
+		t.Run(policy, func(t *testing.T) {
+			env := map[string]string{"TEST_HTTP_ADDR": "127.0.0.1:8099", "TEST_LOG_SERVICE": "", "TEST_SERVICE": "", "TEST_LABEL": ""}
+			opts := EnvOptions{Prefix: "TEST_", Empty: policy, Aliases: ServerEnvAliases("TEST_", "server"), Lookup: func(k string) (string, bool) { v, ok := env[k]; return v, ok }}
+			got, err := OverlayEnv(base, opts)
+			if policy == "reject" {
+				if err == nil || !strings.Contains(err.Error(), "empty") {
+					t.Fatal(err)
+				}
+				return
+			}
+			if err != nil {
+				t.Fatal(err)
+			}
+			if got.Server.Address != "127.0.0.1:8099" {
+				t.Fatal("alias ignored")
+			}
+			if policy == "allow" && got.Label != "" || policy == "ignore" && got.Label != "base" {
+				t.Fatal("empty policy differs")
+			}
+			env["TEST_SERVER_ADDRESS"] = "127.0.0.1:9001"
+			env["TEST_HTTP_READ_TIMEOUT"] = "3s"
+			env["TEST_ENABLE_LOGGER"] = "false"
+			env["TEST_TRUSTED_PROXIES"] = `["127.0.0.1"]`
+			got, err = OverlayEnv(base, opts)
+			if err != nil || got.Server.Address != "127.0.0.1:9001" || got.Server.HTTP.ReadTimeout != 3*time.Second || got.Server.EnableLogger || len(got.Server.TrustedProxies) != 1 {
+				t.Fatal(got, err)
+			}
+			env["TEST_SERVER_ADDRESS"] = ""
+			got, err = OverlayEnv(base, opts)
+			if err != nil {
+				t.Fatal(err)
+			}
+			expected := ""
+			if policy == "ignore" {
+				expected = base.Server.Address
+			}
+			if got.Server.Address != expected {
+				t.Fatal("empty canonical unexpectedly fell through to alias")
+			}
+		})
+	}
+	if base.Server.Address != ":8080" || base.Label != "base" {
+		t.Fatal("defaults mutated")
+	}
+}
+func TestAliasTypeErrorsDoNotExposeValue(t *testing.T) {
+	opts := EnvOptions{Prefix: "X_", Empty: "reject", Aliases: ServerEnvAliases("X_", ""), Lookup: func(k string) (string, bool) { return "private-invalid", k == "X_HTTP_READ_TIMEOUT" }}
+	if _, err := OverlayEnv(Default(), opts); err == nil || strings.Contains(err.Error(), "private-invalid") {
+		t.Fatal(err)
+	}
+}
--- a/config/bind.go
+++ b/config/bind.go
@@ -0,0 +1,320 @@
+package config
+
+import (
+	"encoding/json"
+	"fmt"
+	"reflect"
+	"sort"
+	"strings"
+)
+
+var jsonUnmarshalerType = reflect.TypeOf((*json.Unmarshaler)(nil)).Elem()
+
+type documentBinder struct {
+	doc   Document
+	nodes int
+}
+
+func (b *documentBinder) step(path string, depth int) error {
+	b.nodes++
+	if depth > maxConfigDepth || b.nodes > maxConfigNodes {
+		return b.doc.diagnostic(path, "configuration nesting or node limit exceeded", nil)
+	}
+	return nil
+}
+
+func bindDocument[T any](doc Document, defaults T) (T, error) {
+	var zero T
+	base := reflect.ValueOf(&defaults).Elem()
+	if base.Kind() != reflect.Struct && (base.Kind() != reflect.Pointer || base.Type().Elem().Kind() != reflect.Struct) {
+		return zero, &Error{Reason: "project configuration must be a struct"}
+	}
+	result, err := cloneConfiguration(base, 0)
+	if err != nil {
+		return zero, &Error{Reason: "cannot clone configuration defaults", cause: err}
+	}
+	b := documentBinder{doc: doc}
+	if err = b.bind(doc.Value, result, "", 0, false); err != nil {
+		return zero, err
+	}
+	return result.Interface().(T), nil
+}
+
+func (b *documentBinder) decode(v any, dst reflect.Value, path string) (err error) {
+	defer func() {
+		if recover() != nil {
+			err = b.doc.diagnostic(path, "custom value decoder panicked", nil)
+		}
+	}()
+	raw, err := json.Marshal(v)
+	if err != nil {
+		return b.doc.diagnostic(path, "unsupported configuration value", err)
+	}
+	if err = json.Unmarshal(raw, dst.Addr().Interface()); err != nil {
+		return b.doc.diagnostic(path, "expected a valid "+dst.Type().String(), err)
+	}
+	return nil
+}
+func (b *documentBinder) bind(v any, dst reflect.Value, path string, depth int, quoted bool) error {
+	if err := b.step(path, depth); err != nil {
+		return err
+	}
+	if v == nil {
+		return b.decode(nil, dst, path)
+	} // Preserve encoding/json null semantics.
+	if dst.Kind() == reflect.Pointer {
+		if dst.IsNil() {
+			dst.Set(reflect.New(dst.Type().Elem()))
+		}
+		return b.bind(v, dst.Elem(), path, depth+1, quoted)
+	}
+	if dst.Type() == durationType {
+		var raw string
+		switch x := v.(type) {
+		case string:
+			raw = x
+		case Text:
+			raw = string(x)
+		default:
+			return b.decode(v, dst, path)
+		}
+		if err := parseEnvValue(dst, strings.TrimSpace(raw)); err != nil {
+			return b.doc.diagnostic(path, "expected a duration such as 5s", err)
+		}
+		return nil
+	}
+	if dst.CanAddr() && dst.Addr().Type().Implements(jsonUnmarshalerType) {
+		normalized, err := b.dynamic(v, path, depth+1)
+		if err != nil {
+			return err
+		}
+		return b.decode(normalized, dst, path)
+	}
+	if dst.CanAddr() && dst.Addr().Type().Implements(textType) {
+		if text, ok := v.(Text); ok {
+			v = string(text)
+		}
+		return b.decode(v, dst, path)
+	}
+	if text, ok := v.(Text); ok {
+		if dst.Kind() == reflect.String || dst.Kind() == reflect.Interface || (dst.Kind() == reflect.Slice && dst.Type().Elem().Kind() == reflect.Uint8) {
+			return b.decode(string(text), dst, path)
+		}
+		switch dst.Kind() {
+		case reflect.Bool, reflect.Int, reflect.Int8, reflect.Int16, reflect.Int32, reflect.Int64, reflect.Uint, reflect.Uint8, reflect.Uint16, reflect.Uint32, reflect.Uint64, reflect.Float32, reflect.Float64:
+			if err := parseEnvValue(dst, strings.TrimSpace(string(text))); err != nil {
+				return b.doc.diagnostic(path, "expected a valid "+dst.Type().String(), err)
+			}
+			return nil
+		default:
+			return b.doc.diagnostic(path, "expected an object or array, not scalar text", nil)
+		}
+	}
+	if quoted {
+		s, ok := v.(string)
+		if !ok {
+			return b.doc.diagnostic(path, "expected a JSON-encoded string", nil)
+		}
+		if err := json.Unmarshal([]byte(s), dst.Addr().Interface()); err != nil {
+			return b.doc.diagnostic(path, "invalid string-encoded value", err)
+		}
+		return nil
+	}
+	switch dst.Kind() {
+	case reflect.Struct:
+		m, ok := v.(map[string]any)
+		if !ok {
+			return b.doc.diagnostic(path, "expected an object", nil)
+		}
+		fields := configurationFields(dst.Type())
+		used := map[string]bool{}
+		for _, name := range sortedKeys(m) {
+			child := joinField(path, name)
+			f, ok := fields[name]
+			canonical := name
+			if !ok {
+				for n, field := range fields {
+					if strings.EqualFold(n, name) {
+						if ok {
+							return b.doc.diagnostic(child, "ambiguous field name", nil)
+						}
+						f, ok, canonical = field, true, n
+					}
+				}
+			}
+			if !ok {
+				return b.doc.diagnostic(child, "unknown field", nil)
+			}
+			if used[canonical] {
+				return b.doc.diagnostic(child, "duplicate field binding", nil)
+			}
+			used[canonical] = true
+			target := dst
+			for _, index := range f.Index {
+				if target.Kind() == reflect.Pointer {
+					if target.IsNil() {
+						if !target.CanSet() {
+							return b.doc.diagnostic(child, "field cannot be assigned", nil)
+						}
+						target.Set(reflect.New(target.Type().Elem()))
+					}
+					target = target.Elem()
+				}
+				target = target.Field(index)
+			}
+			if !target.CanSet() {
+				return b.doc.diagnostic(child, "field cannot be assigned", nil)
+			}
+			if err := b.bind(m[name], target, child, depth+1, strings.Contains(","+f.Tag.Get("json")+",", ",string,")); err != nil {
+				return err
+			}
+		}
+		return nil
+	case reflect.Map:
+		m, ok := v.(map[string]any)
+		if !ok || dst.Type().Key().Kind() != reflect.String {
+			return b.doc.diagnostic(path, "expected an object with string keys", nil)
+		}
+		if dst.IsNil() {
+			dst.Set(reflect.MakeMap(dst.Type()))
+		}
+		for _, key := range sortedKeys(m) {
+			value := reflect.New(dst.Type().Elem()).Elem()
+			if err := b.bind(m[key], value, joinField(path, key), depth+1, false); err != nil {
+				return err
+			}
+			k := reflect.New(dst.Type().Key()).Elem()
+			k.SetString(key)
+			dst.SetMapIndex(k, value)
+		}
+		return nil
+	case reflect.Slice, reflect.Array:
+		if _, ok := v.(string); ok && dst.Kind() == reflect.Slice && dst.Type().Elem().Kind() == reflect.Uint8 {
+			return b.decode(v, dst, path)
+		}
+		items, ok := v.([]any)
+		if !ok {
+			return b.doc.diagnostic(path, "expected an array", nil)
+		}
+		if dst.Kind() == reflect.Array && len(items) != dst.Len() {
+			return b.doc.diagnostic(path, "array length does not match its declared type", nil)
+		}
+		if dst.Kind() == reflect.Slice {
+			dst.Set(reflect.MakeSlice(dst.Type(), len(items), len(items)))
+		}
+		for i, value := range items {
+			if err := b.bind(value, dst.Index(i), fmt.Sprintf("%s[%d]", path, i), depth+1, false); err != nil {
+				return err
+			}
+		}
+		return nil
+	case reflect.Interface:
+		v, err := b.dynamic(v, path, depth+1)
+		if err != nil {
+			return err
+		}
+		if dst.Type().NumMethod() == 0 {
+			dst.Set(reflect.ValueOf(v))
+			return nil
+		}
+		return b.decode(v, dst, path)
+	default:
+		return b.decode(v, dst, path)
+	}
+}
+func sortedKeys(m map[string]any) []string {
+	keys := make([]string, 0, len(m))
+	for k := range m {
+		keys = append(keys, k)
+	}
+	sort.Strings(keys)
+	return keys
+}
+func (b *documentBinder) dynamic(v any, path string, depth int) (any, error) {
+	if err := b.step(path, depth); err != nil {
+		return nil, err
+	}
+	switch x := v.(type) {
+	case Text:
+		return string(x), nil
+	case map[string]any:
+		out := make(map[string]any, len(x))
+		for _, k := range sortedKeys(x) {
+			c, err := b.dynamic(x[k], joinField(path, k), depth+1)
+			if err != nil {
+				return nil, err
+			}
+			out[k] = c
+		}
+		return out, nil
+	case []any:
+		out := make([]any, len(x))
+		for i, v := range x {
+			c, err := b.dynamic(v, fmt.Sprintf("%s[%d]", path, i), depth+1)
+			if err != nil {
+				return nil, err
+			}
+			out[i] = c
+		}
+		return out, nil
+	default:
+		return v, nil
+	}
+}
+
+// Match encoding/json's field promotion: the shallowest declaration wins;
+// explicit tags win ties, and ambiguous fields remain unavailable.
+func configurationFields(t reflect.Type) map[string]reflect.StructField {
+	type candidate struct {
+		field  reflect.StructField
+		tagged bool
+	}
+	candidates := map[string][]candidate{}
+	var visit func(reflect.Type, []int, map[reflect.Type]bool)
+	visit = func(current reflect.Type, prefix []int, visiting map[reflect.Type]bool) {
+		if visiting[current] {
+			return
+		}
+		visiting[current] = true
+		defer delete(visiting, current)
+		for i := 0; i < current.NumField(); i++ {
+			f := current.Field(i)
+			name := strings.Split(f.Tag.Get("json"), ",")[0]
+			if name == "-" {
+				continue
+			}
+			child := f.Type
+			if child.Kind() == reflect.Pointer {
+				child = child.Elem()
+			}
+			if f.PkgPath != "" && (!f.Anonymous || child.Kind() != reflect.Struct) {
+				continue
+			}
+			f.Index = append(append([]int(nil), prefix...), i)
+			if name == "" && f.Anonymous && child.Kind() == reflect.Struct {
+				visit(child, f.Index, visiting)
+				continue
+			}
+			tagged := name != ""
+			if name == "" {
+				name = f.Name
+			}
+			candidates[name] = append(candidates[name], candidate{f, tagged})
+		}
+	}
+	visit(t, nil, map[reflect.Type]bool{})
+	fields := map[string]reflect.StructField{}
+	for name, list := range candidates {
+		sort.Slice(list, func(i, j int) bool {
+			if len(list[i].field.Index) != len(list[j].field.Index) {
+				return len(list[i].field.Index) < len(list[j].field.Index)
+			}
+			return list[i].tagged && !list[j].tagged
+		})
+		if len(list) > 1 && len(list[0].field.Index) == len(list[1].field.Index) && list[0].tagged == list[1].tagged {
+			continue
+		}
+		fields[name] = list[0].field
+	}
+	return fields
+}
--- a/config/config.go
+++ b/config/config.go
@@ -62,19 +62,19 @@ func Default() Config {
 // Validate checks configuration values before an application starts.
 func (c Config) Validate() error {
 	if err := c.Lifecycle.Validate(); err != nil {
-		return err
+		return AtField("lifecycle", err)
 	}
 	if err := c.Request.Validate(); err != nil {
-		return err
+		return AtField("request", err)
 	}
 	if err := c.Log.Validate(); err != nil {
-		return err
+		return AtField("log", err)
 	}
 	if err := c.Endpoints.Validate(); err != nil {
 		return err
 	}
 	if err := c.Errors.Validate(); err != nil {
-		return err
+		return AtField("errors", err)
 	}
 	encoder := c.ResponseEncoder
 	if encoder == nil {
@@ -90,7 +90,7 @@ func (c Config) Validate() error {
 		return err
 	}
 	if err := c.Response.Validate(); err != nil {
-		return err
+		return AtField("response", err)
 	}
 	if c.SlowRequestThreshold < 0 {
 		return &ConfigError{Field: "slowRequestThreshold", Message: "must be nonnegative"}
@@ -99,13 +99,13 @@ func (c Config) Validate() error {
 		return &ConfigError{Field: "address", Message: "is required"}
 	}
 	if strings.TrimSpace(c.RequestIDHeader) == "" {
-		return &ConfigError{Field: "request_id_header", Message: "is required"}
+		return &ConfigError{Field: "requestIdHeader", Message: "is required"}
 	}
 	if c.ShutdownTimeout <= 0 {
-		return &ConfigError{Field: "shutdown_timeout", Message: "must be positive"}
+		return &ConfigError{Field: "shutdownTimeout", Message: "must be positive"}
 	}
 	if _, err := httpx.NewClientIPResolver(c.TrustedProxies...); err != nil {
-		return &ConfigError{Field: "trusted_proxies", Message: err.Error()}
+		return &Error{Field: "trustedProxies", Reason: "expected IP addresses or CIDRs", cause: err}
 	}
 	return c.ValidateTransport()
 }
--- a/config/config_test.go
+++ b/config/config_test.go
@@ -112,7 +112,7 @@ func TestLoadFromEnvRejectsInvalidValues(t *testing.T) {

 	t.Setenv("GO_OMNI_SHUTDOWN_TIMEOUT", "1s")
 	t.Setenv("GO_OMNI_TRUSTED_PROXIES", "proxy.example.com")
-	if _, err := LoadFromEnv(""); err == nil || !strings.Contains(err.Error(), "trusted_proxies") {
+	if _, err := LoadFromEnv(""); err == nil || !strings.Contains(err.Error(), "trustedProxies") {
 		t.Fatalf("expected invalid trusted proxy error, got %v", err)
 	}
 	t.Setenv("GO_OMNI_TRUSTED_PROXIES", "")
@@ -123,7 +123,7 @@ func TestLoadFromEnvRejectsInvalidValues(t *testing.T) {
 	}
 	cfg = Default()
 	cfg.RequestIDHeader = " "
-	if err := cfg.Validate(); err == nil || !strings.Contains(err.Error(), "request_id_header") {
+	if err := cfg.Validate(); err == nil || !strings.Contains(err.Error(), "requestIdHeader") {
 		t.Fatalf("expected invalid request header error, got %v", err)
 	}
 }
--- a/config/decoders.go
+++ b/config/decoders.go
@@ -0,0 +1,398 @@
+package config
+
+import (
+	"bytes"
+	"encoding/json"
+	"encoding/xml"
+	"errors"
+	"fmt"
+	"io"
+	"regexp"
+	"sort"
+	"strconv"
+	"strings"
+	"unicode/utf8"
+
+	"gopkg.in/yaml.v3"
+)
+
+type JSONDecoder struct{}
+type YAMLDecoder struct{}
+type XMLDecoder struct{}
+
+type parseState struct {
+	doc   Document
+	nodes int
+}
+
+func newParseState() *parseState { return &parseState{doc: Document{Positions: map[string]Position{}}} }
+func (p *parseState) enter(path string, pos Position, depth int) error {
+	p.nodes++
+	p.doc.Positions[path] = pos
+	if depth > maxConfigDepth || p.nodes > maxConfigNodes {
+		return p.doc.diagnostic(path, "configuration nesting or node limit exceeded", nil)
+	}
+	return nil
+}
+
+type sourcePositions struct{ starts []int }
+
+func newSourcePositions(data []byte) sourcePositions {
+	p := sourcePositions{starts: []int{0}}
+	for i, c := range data {
+		if c == '\n' {
+			p.starts = append(p.starts, i+1)
+		}
+	}
+	return p
+}
+func (p sourcePositions) at(offset int64) Position {
+	if offset < 0 {
+		offset = 0
+	}
+	i := sort.Search(len(p.starts), func(i int) bool { return int64(p.starts[i]) > offset }) - 1
+	return Position{Line: i + 1, Column: int(offset) - p.starts[i] + 1}
+}
+
+var yamlLine = regexp.MustCompile(`line ([0-9]+)`)
+
+func yamlSyntax(err error) *Error {
+	d := &Error{Reason: "invalid YAML syntax", cause: err}
+	if m := yamlLine.FindStringSubmatch(err.Error()); len(m) == 2 {
+		d.Line, _ = strconv.Atoi(m[1])
+		d.Column = 1
+	}
+	return d
+}
+func (JSONDecoder) Decode(data []byte) (Document, error) {
+	p := newParseState()
+	if len(data) > maxConfigBytes {
+		return p.doc, &Error{Reason: "file exceeds 1 MiB"}
+	}
+	if !utf8.Valid(data) {
+		return p.doc, &Error{Reason: "configuration must be UTF-8"}
+	}
+	positions := newSourcePositions(data)
+	d := json.NewDecoder(bytes.NewReader(data))
+	d.UseNumber()
+	var parse func(string, int) (any, error)
+	parse = func(path string, depth int) (any, error) {
+		offset := d.InputOffset()
+		for offset < int64(len(data)) && strings.ContainsRune(" \t\r\n:,", rune(data[offset])) {
+			offset++
+		}
+		if err := p.enter(path, positions.at(offset), depth); err != nil {
+			return nil, err
+		}
+		token, err := d.Token()
+		if err != nil {
+			pos := positions.at(d.InputOffset())
+			var syntax *json.SyntaxError
+			if errors.As(err, &syntax) {
+				pos = positions.at(syntax.Offset - 1)
+			}
+			return nil, &Error{Field: path, Line: pos.Line, Column: pos.Column, Reason: "invalid JSON syntax", cause: err}
+		}
+		if delim, ok := token.(json.Delim); ok {
+			switch delim {
+			case '{':
+				out := map[string]any{}
+				for d.More() {
+					k, e := d.Token()
+					if e != nil {
+						return nil, p.doc.diagnostic(path, "invalid object key", e)
+					}
+					key, ok := k.(string)
+					if !ok {
+						return nil, p.doc.diagnostic(path, "object key must be a string", nil)
+					}
+					child := joinField(path, key)
+					if _, exists := out[key]; exists {
+						return nil, p.doc.diagnostic(child, "duplicate field", nil)
+					}
+					out[key], e = parse(child, depth+1)
+					if e != nil {
+						return nil, e
+					}
+				}
+				if _, err = d.Token(); err != nil {
+					return nil, p.doc.diagnostic(path, "unterminated object", err)
+				}
+				return out, nil
+			case '[':
+				out := []any{}
+				for d.More() {
+					v, e := parse(fmt.Sprintf("%s[%d]", path, len(out)), depth+1)
+					if e != nil {
+						return nil, e
+					}
+					out = append(out, v)
+				}
+				if _, err = d.Token(); err != nil {
+					return nil, p.doc.diagnostic(path, "unterminated array", err)
+				}
+				return out, nil
+			default:
+				return nil, p.doc.diagnostic(path, "unexpected JSON delimiter", nil)
+			}
+		}
+		return token, nil
+	}
+	var err error
+	p.doc.Value, err = parse("", 0)
+	if err == nil {
+		if _, e := d.Token(); e != io.EOF {
+			err = p.doc.diagnostic("", "exactly one JSON document required", e)
+		}
+	}
+	return p.doc, err
+}
+
+func (YAMLDecoder) Decode(data []byte) (Document, error) {
+	p := newParseState()
+	if len(data) > maxConfigBytes {
+		return p.doc, &Error{Reason: "file exceeds 1 MiB"}
+	}
+	if !utf8.Valid(data) {
+		return p.doc, &Error{Reason: "configuration must be UTF-8"}
+	}
+	d := yaml.NewDecoder(bytes.NewReader(data))
+	var root yaml.Node
+	if err := d.Decode(&root); err != nil {
+		return p.doc, yamlSyntax(err)
+	}
+	var extra yaml.Node
+	if err := d.Decode(&extra); err != io.EOF {
+		return p.doc, &Error{Reason: "exactly one YAML document required", cause: err}
+	}
+	var walk func(*yaml.Node, string, int) (any, error)
+	walk = func(n *yaml.Node, path string, depth int) (any, error) {
+		if err := p.enter(path, Position{n.Line, n.Column}, depth); err != nil {
+			return nil, err
+		}
+		switch n.Kind {
+		case yaml.MappingNode:
+			out := map[string]any{}
+			for i := 0; i < len(n.Content); i += 2 {
+				k, v := n.Content[i], n.Content[i+1]
+				if k.Tag != "!!str" {
+					return nil, p.doc.diagnostic(path, "mapping keys must be strings; merge keys are not supported", nil)
+				}
+				child := joinField(path, k.Value)
+				if _, ok := out[k.Value]; ok {
+					return nil, &Error{Field: child, Line: k.Line, Column: k.Column, Reason: "duplicate field"}
+				}
+				x, err := walk(v, child, depth+1)
+				if err != nil {
+					return nil, err
+				}
+				out[k.Value] = x
+			}
+			return out, nil
+		case yaml.SequenceNode:
+			out := make([]any, len(n.Content))
+			for i, c := range n.Content {
+				var err error
+				out[i], err = walk(c, fmt.Sprintf("%s[%d]", path, i), depth+1)
+				if err != nil {
+					return nil, err
+				}
+			}
+			return out, nil
+		case yaml.AliasNode:
+			return nil, p.doc.diagnostic(path, "YAML aliases are not supported", nil)
+		case yaml.ScalarNode:
+			switch n.Tag {
+			case "!!str", "!!timestamp":
+				return n.Value, nil
+			case "!!null":
+				return nil, nil
+			case "!!bool", "!!int", "!!float":
+				var v any
+				if err := n.Decode(&v); err != nil {
+					return nil, p.doc.diagnostic(path, "invalid YAML scalar", err)
+				}
+				raw, err := json.Marshal(v)
+				if err != nil {
+					return nil, p.doc.diagnostic(path, "number must be finite", err)
+				}
+				var out any
+				dec := json.NewDecoder(bytes.NewReader(raw))
+				dec.UseNumber()
+				if err = dec.Decode(&out); err != nil {
+					return nil, p.doc.diagnostic(path, "invalid YAML scalar", err)
+				}
+				return out, nil
+			default:
+				return nil, p.doc.diagnostic(path, "unsupported YAML tag", nil)
+			}
+		}
+		return nil, p.doc.diagnostic(path, "unsupported YAML node", nil)
+	}
+	if len(root.Content) != 1 {
+		return p.doc, &Error{Reason: "one nonempty YAML document required"}
+	}
+	var err error
+	p.doc.Value, err = walk(root.Content[0], "", 0)
+	return p.doc, err
+}
+
+// XML uses a config root, element field names, type="array" with item children,
+// type="object" for empty objects, and type="null" for explicit null. Scalar
+// text is bound using the destination type; optional number/bool/string types
+// let dynamic any values preserve their intended JSON type.
+func (XMLDecoder) Decode(data []byte) (Document, error) {
+	p := newParseState()
+	if len(data) > maxConfigBytes {
+		return p.doc, &Error{Reason: "file exceeds 1 MiB"}
+	}
+	if !utf8.Valid(data) {
+		return p.doc, &Error{Reason: "configuration must be UTF-8"}
+	}
+	d := xml.NewDecoder(bytes.NewReader(data))
+	var parse func(xml.StartElement, string, int, Position) (any, error)
+	parse = func(start xml.StartElement, path string, depth int, pos Position) (any, error) {
+		if err := p.enter(path, pos, depth); err != nil {
+			return nil, err
+		}
+		if start.Name.Space != "" {
+			return nil, p.doc.diagnostic(path, "XML namespaces are not supported", nil)
+		}
+		kind := ""
+		attrSeen := false
+		for _, a := range start.Attr {
+			if a.Name.Space != "" || a.Name.Local != "type" || attrSeen {
+				return nil, p.doc.diagnostic(path, "only one XML type attribute is supported", nil)
+			}
+			kind = a.Value
+			attrSeen = true
+		}
+		if depth == 0 && kind == "" {
+			kind = "object"
+		}
+		switch kind {
+		case "", "object", "array", "null", "string", "number", "bool":
+		default:
+			return nil, p.doc.diagnostic(path, "unsupported XML type", nil)
+		}
+		children := map[string]any{}
+		array := []any{}
+		var text strings.Builder
+		for {
+			line, column := d.InputPos()
+			token, err := d.Token()
+			if err != nil {
+				return nil, &Error{Field: path, Line: line, Column: column, Reason: "invalid XML syntax", cause: err}
+			}
+			switch x := token.(type) {
+			case xml.StartElement:
+				if kind != "" && kind != "object" && kind != "array" {
+					return nil, p.doc.diagnostic(path, "scalar XML element cannot contain children", nil)
+				}
+				child := joinField(path, x.Name.Local)
+				if kind == "array" {
+					if x.Name.Local != "item" {
+						return nil, p.doc.diagnostic(path, "XML array children must be item elements", nil)
+					}
+					child = fmt.Sprintf("%s[%d]", path, len(array))
+				} else if _, ok := children[x.Name.Local]; ok {
+					return nil, p.doc.diagnostic(child, "duplicate field; use type=\"array\" for lists", nil)
+				}
+				v, e := parse(x, child, depth+1, Position{line, column})
+				if e != nil {
+					return nil, e
+				}
+				if kind == "array" {
+					array = append(array, v)
+				} else {
+					children[x.Name.Local] = v
+				}
+			case xml.CharData:
+				text.Write([]byte(x))
+			case xml.Comment:
+			case xml.EndElement:
+				raw := text.String()
+				if len(children) > 0 || kind == "array" || kind == "object" {
+					if strings.TrimSpace(raw) != "" {
+						return nil, p.doc.diagnostic(path, "mixed XML text and elements are not supported", nil)
+					}
+					if kind == "array" {
+						return array, nil
+					}
+					return children, nil
+				}
+				switch kind {
+				case "null":
+					if strings.TrimSpace(raw) != "" {
+						return nil, p.doc.diagnostic(path, "null element must be empty", nil)
+					}
+					return nil, nil
+				case "string":
+					return raw, nil
+				case "number":
+					var n any
+					dec := json.NewDecoder(strings.NewReader(strings.TrimSpace(raw)))
+					dec.UseNumber()
+					if err := dec.Decode(&n); err != nil {
+						return nil, p.doc.diagnostic(path, "invalid number", err)
+					}
+					if _, ok := n.(json.Number); !ok {
+						return nil, p.doc.diagnostic(path, "expected number", nil)
+					}
+					if _, e := dec.Token(); e != io.EOF {
+						return nil, p.doc.diagnostic(path, "invalid number", e)
+					}
+					return n, nil
+				case "bool":
+					b, e := strconv.ParseBool(strings.TrimSpace(raw))
+					if e != nil {
+						return nil, p.doc.diagnostic(path, "expected boolean", e)
+					}
+					return b, nil
+				}
+				return Text(raw), nil
+			default:
+				return nil, p.doc.diagnostic(path, "XML directives and processing instructions are not supported", nil)
+			}
+		}
+	}
+	found := false
+	prolog := false
+	for {
+		line, column := d.InputPos()
+		token, err := d.Token()
+		if err == io.EOF {
+			break
+		}
+		if err != nil {
+			return p.doc, &Error{Line: line, Column: column, Reason: "invalid XML syntax", cause: err}
+		}
+		switch x := token.(type) {
+		case xml.StartElement:
+			if found || x.Name.Local != "config" {
+				return p.doc, &Error{Line: line, Column: column, Reason: "exactly one config root required"}
+			}
+			found = true
+			p.doc.Value, err = parse(x, "", 0, Position{line, column})
+			if err != nil {
+				return p.doc, err
+			}
+		case xml.CharData:
+			if strings.TrimSpace(string(x)) != "" {
+				return p.doc, &Error{Reason: "unexpected text outside XML root"}
+			}
+		case xml.Comment:
+		case xml.ProcInst:
+			if found || prolog || x.Target != "xml" {
+				return p.doc, &Error{Reason: "XML processing instructions are not supported"}
+			}
+			prolog = true
+		default:
+			return p.doc, &Error{Reason: "XML directives are not supported"}
+		}
+	}
+	if !found {
+		return p.doc, &Error{Reason: "config root required"}
+	}
+	return p.doc, nil
+}
--- a/config/diagnostic.go
+++ b/config/diagnostic.go
@@ -0,0 +1,94 @@
+package config
+
+import (
+	"errors"
+	"fmt"
+	"strings"
+)
+
+// Error is a value-free diagnostic. Cause may contain private parser details;
+// errors.Is/As remain available, but Error never formats Cause automatically.
+type Error struct {
+	File, Field, Env, Reason string
+	Line, Column             int
+	cause                    error
+}
+
+func (e *Error) Error() string {
+	where := "config"
+	if e.File != "" {
+		where = fmt.Sprintf("config %q", e.File)
+	}
+	if e.Line > 0 {
+		where += fmt.Sprintf(":%d:%d", e.Line, e.Column)
+	}
+	if e.Env != "" {
+		where += fmt.Sprintf(" env %q", e.Env)
+	}
+	if e.Field != "" {
+		where += fmt.Sprintf(" field %q", e.Field)
+	}
+	return where + ": " + e.Reason
+}
+func (e *Error) Unwrap() error { return e.cause }
+
+// DecodeError is retained for callers of errors.As from earlier releases.
+type DecodeError = Error
+
+// Invalid reports a public, value-free validation reason for a configuration field.
+func Invalid(field, reason string) error { return &ConfigError{Field: field, Message: reason} }
+
+// AtField prefixes a nested validation error without losing its original cause.
+// Unstructured validation errors are deliberately not echoed; use Invalid when
+// a custom validator needs a public reason rather than a private error message.
+func AtField(field string, err error) error {
+	if err == nil {
+		return nil
+	}
+	d := validationError(err)
+	d.Field = joinField(field, d.Field)
+	return d
+}
+func validationError(err error) *Error {
+	var d *Error
+	if errors.As(err, &d) {
+		out := *d
+		out.cause = err
+		return &out
+	}
+	var c *ConfigError
+	if errors.As(err, &c) {
+		return &Error{Field: c.Field, Reason: c.Message, cause: err}
+	}
+	return &Error{Reason: "validation failed", cause: err}
+}
+func joinField(parent, child string) string {
+	if parent == "" {
+		return child
+	}
+	if child == "" {
+		return parent
+	}
+	if strings.HasPrefix(child, "[") {
+		return parent + child
+	}
+	return parent + "." + child
+}
+
+// Position uses one-based source line/column numbers. Zero means unavailable.
+type Position struct{ Line, Column int }
+
+// Document is the common decoder result. Values use JSON-compatible data:
+// string, bool, json.Number, nil, []any, map[string]any. Text is available for
+// formats such as XML whose scalar tokens have no inherent JSON type.
+type Document struct {
+	Value     any
+	Positions map[string]Position
+}
+
+type Text string
+
+func (d Document) diagnostic(field, reason string, cause error) *Error {
+	p := d.Positions[field]
+	return &Error{Field: field, Reason: reason, Line: p.Line, Column: p.Column, cause: cause}
+}
--- a/config/env.go
+++ b/config/env.go
@@ -1,138 +1,83 @@
 package config

 import (
-	"fmt"
+	"encoding/json"
 	"os"
-	"strconv"
 	"strings"
-	"time"
 )

 const defaultEnvPrefix = "GO_OMNI_"

-// LoadFromEnv loads application settings from GO_OMNI_* variables. The
-// database settings remain owned by database.ConfigFromEnv.
-func LoadFromEnv(prefix string) (Config, error) {
-	return applyEnv(Default(), prefix)
+// ServerEnvAliases returns the documented short names for Config fields.
+// field is the JSON path of Config in a project (usually "server"), or ""
+// for Config itself. Canonical names win over aliases. Both use the same
+// EnvOptions.Empty/Lookup and typed parser; collections use JSON syntax.
+func ServerEnvAliases(prefix, field string) map[string][]string {
+	root := prefix
+	if field != "" {
+		for _, part := range strings.Split(field, ".") {
+			root += envName(part) + "_"
+		}
+	}
+	names := map[string]string{
+		"ADDRESS": "HTTP_ADDR", "TRANSPORT": "TRANSPORT", "TLS_CERT_FILE": "TLS_CERT_FILE", "TLS_KEY_FILE": "TLS_KEY_FILE",
+		"REQUEST_ID_HEADER": "REQUEST_ID_HEADER", "ENABLE_LOGGER": "ENABLE_LOGGER", "SLOW_REQUEST_THRESHOLD": "SLOW_REQUEST_THRESHOLD",
+		"TRUSTED_PROXIES": "TRUSTED_PROXIES", "SHUTDOWN_TIMEOUT": "SHUTDOWN_TIMEOUT",
+		"LOG_LEVEL": "LOG_LEVEL", "LOG_FORMAT": "LOG_FORMAT", "LOG_OUTPUT": "LOG_OUTPUT", "LOG_FILE": "LOG_FILE", "LOG_SERVICE": "SERVICE", "LOG_ENVIRONMENT": "ENVIRONMENT", "LOG_ADD_SOURCE": "LOG_ADD_SOURCE",
+		"HTTP_READ_HEADER_TIMEOUT": "HTTP_READ_HEADER_TIMEOUT", "HTTP_READ_TIMEOUT": "HTTP_READ_TIMEOUT", "HTTP_WRITE_TIMEOUT": "HTTP_WRITE_TIMEOUT", "HTTP_IDLE_TIMEOUT": "HTTP_IDLE_TIMEOUT", "HTTP_MAX_HEADER_BYTES": "HTTP_MAX_HEADER_BYTES",
+		"LIFECYCLE_STOP_TIMEOUT": "LIFECYCLE_STOP_TIMEOUT", "LIFECYCLE_DRAIN_TIMEOUT": "LIFECYCLE_DRAIN_TIMEOUT", "LIFECYCLE_CANCEL_TIMEOUT": "LIFECYCLE_CANCEL_TIMEOUT",
+	}
+	for _, endpoint := range []string{"LIVENESS", "READINESS", "OPENAPI"} {
+		for _, part := range []string{"ENABLED", "PATH", "RESPONSE_MODE"} {
+			if endpoint == "OPENAPI" && part == "RESPONSE_MODE" {
+				continue
+			}
+			name := "ENDPOINTS_" + endpoint + "_" + part
+			names[name] = name
+		}
+	}
+	aliases := map[string][]string{}
+	for key, alias := range names {
+		if root+key != prefix+alias {
+			aliases[root+key] = []string{prefix + alias}
+		}
+	}
+	return aliases
 }

-// ApplyEnv overlays nonempty environment values on a caller's defaults or file
-// settings, then validates the result. Caller-owned slices are not retained.
+// LoadFromEnv loads defaults using the legacy short-name conventions.
+func LoadFromEnv(prefix string) (Config, error) { return ApplyEnv(Default(), prefix) }
+
+// ApplyEnv retains legacy whitespace trimming, ignored empty variables and
+// comma-separated TRUSTED_PROXIES. New projects should use OverlayEnv with
+// ServerEnvAliases for one explicit empty-value policy across the whole config.
 func ApplyEnv(defaults Config, prefix string) (Config, error) {
-	defaults.Errors = defaults.Errors.Clone()
-	defaults.TrustedProxies = append([]string(nil), defaults.TrustedProxies...)
-	defaults.Log.RedactKeys = append([]string(nil), defaults.Log.RedactKeys...)
-	return applyEnv(defaults, prefix)
-}
-
-func applyEnv(cfg Config, prefix string) (Config, error) {
 	prefix = strings.TrimSpace(prefix)
 	if prefix == "" {
 		prefix = defaultEnvPrefix
 	}
-	cfg.Address = envString(prefix+"HTTP_ADDR", cfg.Address)
-	cfg.Transport = envString(prefix+"TRANSPORT", cfg.Transport)
-	cfg.TLS.CertFile = envString(prefix+"TLS_CERT_FILE", cfg.TLS.CertFile)
-	cfg.TLS.KeyFile = envString(prefix+"TLS_KEY_FILE", cfg.TLS.KeyFile)
-	cfg.RequestIDHeader = envString(prefix+"REQUEST_ID_HEADER", cfg.RequestIDHeader)
-	if value := strings.TrimSpace(os.Getenv(prefix + "TRUSTED_PROXIES")); value != "" {
-		cfg.TrustedProxies = strings.Split(value, ",")
-		for i := range cfg.TrustedProxies {
-			cfg.TrustedProxies[i] = strings.TrimSpace(cfg.TrustedProxies[i])
-		}
-	}
-	cfg.Log.Level = envString(prefix+"LOG_LEVEL", cfg.Log.Level)
-	cfg.Log.Format = envString(prefix+"LOG_FORMAT", cfg.Log.Format)
-	cfg.Log.Output = envString(prefix+"LOG_OUTPUT", cfg.Log.Output)
-	cfg.Log.File = envString(prefix+"LOG_FILE", cfg.Log.File)
-	cfg.Log.Service = envString(prefix+"SERVICE", cfg.Log.Service)
-	cfg.Log.Environment = envString(prefix+"ENVIRONMENT", cfg.Log.Environment)
-
-	var err error
-	for _, endpoint := range []struct {
-		name    string
-		enabled *bool
-		path    *string
-		mode    *string
-	}{
-		{"LIVENESS", &cfg.Endpoints.Liveness.Enabled, &cfg.Endpoints.Liveness.Path, &cfg.Endpoints.Liveness.ResponseMode},
-		{"READINESS", &cfg.Endpoints.Readiness.Enabled, &cfg.Endpoints.Readiness.Path, &cfg.Endpoints.Readiness.ResponseMode},
-		{"OPENAPI", &cfg.Endpoints.OpenAPI.Enabled, &cfg.Endpoints.OpenAPI.Path, nil},
-	} {
-		key := prefix + "ENDPOINTS_" + endpoint.name
-		*endpoint.enabled, err = envBool(key+"_ENABLED", *endpoint.enabled)
-		if err != nil {
-			return Config{}, err
-		}
-		*endpoint.path = envString(key+"_PATH", *endpoint.path)
-		if endpoint.mode != nil {
-			*endpoint.mode = envString(key+"_RESPONSE_MODE", *endpoint.mode)
-		}
-	}
-	for _, field := range []struct {
-		name  string
-		value *time.Duration
-	}{
-		{"HTTP_READ_HEADER_TIMEOUT", &cfg.HTTP.ReadHeaderTimeout},
-		{"HTTP_READ_TIMEOUT", &cfg.HTTP.ReadTimeout},
-		{"HTTP_WRITE_TIMEOUT", &cfg.HTTP.WriteTimeout},
-		{"HTTP_IDLE_TIMEOUT", &cfg.HTTP.IdleTimeout},
-		{"LIFECYCLE_STOP_TIMEOUT", &cfg.Lifecycle.StopTimeout},
-		{"LIFECYCLE_DRAIN_TIMEOUT", &cfg.Lifecycle.DrainTimeout},
-		{"LIFECYCLE_CANCEL_TIMEOUT", &cfg.Lifecycle.CancelTimeout},
-	} {
-		if value := strings.TrimSpace(os.Getenv(prefix + field.name)); value != "" {
-			*field.value, err = time.ParseDuration(value)
-			if err != nil {
-				return Config{}, fmt.Errorf("%s%s must be a duration: %w", prefix, field.name, err)
+	lookup := func(key string) (string, bool) {
+		raw, ok := os.LookupEnv(key)
+		raw = strings.TrimSpace(raw)
+		if ok && raw != "" && key == prefix+"TRUSTED_PROXIES" && !strings.HasPrefix(raw, "[") {
+			values := strings.Split(raw, ",")
+			for i := range values {
+				values[i] = strings.TrimSpace(values[i])
 			}
+			data, _ := json.Marshal(values)
+			raw = string(data)
 		}
+		return raw, ok
 	}
-	if value := strings.TrimSpace(os.Getenv(prefix + "HTTP_MAX_HEADER_BYTES")); value != "" {
-		cfg.HTTP.MaxHeaderBytes, err = strconv.Atoi(value)
-		if err != nil {
-			return Config{}, fmt.Errorf("%sHTTP_MAX_HEADER_BYTES must be an integer: %w", prefix, err)
-		}
-	}
-	if cfg.EnableLogger, err = envBool(prefix+"ENABLE_LOGGER", cfg.EnableLogger); err != nil {
+	defaults.Errors = defaults.Errors.Clone()
+	defaults.TrustedProxies = append([]string(nil), defaults.TrustedProxies...)
+	defaults.Log.RedactKeys = append([]string(nil), defaults.Log.RedactKeys...)
+	cfg, err := OverlayEnv(defaults, EnvOptions{Prefix: prefix, Empty: "ignore", Lookup: lookup, Aliases: ServerEnvAliases(prefix, "")})
+	if err != nil {
 		return Config{}, err
 	}
-	if cfg.Log.AddSource, err = envBool(prefix+"LOG_ADD_SOURCE", cfg.Log.AddSource); err != nil {
-		return Config{}, err
-	}
-	if value := strings.TrimSpace(os.Getenv(prefix + "SLOW_REQUEST_THRESHOLD")); value != "" {
-		cfg.SlowRequestThreshold, err = time.ParseDuration(value)
-		if err != nil {
-			return Config{}, fmt.Errorf("%sSLOW_REQUEST_THRESHOLD must be a duration: %w", prefix, err)
-		}
-	}
-	if value := strings.TrimSpace(os.Getenv(prefix + "SHUTDOWN_TIMEOUT")); value != "" {
-		cfg.ShutdownTimeout, err = time.ParseDuration(value)
-		if err != nil {
-			return Config{}, fmt.Errorf("%sSHUTDOWN_TIMEOUT must be a duration: %w", prefix, err)
-		}
-	}
-	if err := cfg.Validate(); err != nil {
+	if err = cfg.Validate(); err != nil {
 		return Config{}, err
 	}
 	return cfg, nil
 }
-
-func envString(key, fallback string) string {
-	if value := strings.TrimSpace(os.Getenv(key)); value != "" {
-		return value
-	}
-	return fallback
-}
-
-func envBool(key string, fallback bool) (bool, error) {
-	value := strings.TrimSpace(os.Getenv(key))
-	if value == "" {
-		return fallback, nil
-	}
-	parsed, err := strconv.ParseBool(value)
-	if err != nil {
-		return false, fmt.Errorf("%s must be a boolean: %w", key, err)
-	}
-	return parsed, nil
-}
--- a/config/file.go
+++ b/config/file.go
@@ -1,100 +1,16 @@
 package config

 import (
-	"bytes"
 	"context"
-	"encoding/json"
 	"errors"
-	"io"
-	"os"
-	"path/filepath"
 	"reflect"
 	"strings"
 	"sync"
 	"time"

-	apierrors "git.yuntuo.hk/k2safe/go-omni/errors"
 	"git.yuntuo.hk/k2safe/go-omni/logx"
-	"gopkg.in/yaml.v3"
 )

-// DecodeFile merges a bounded JSON/YAML document into defaults. It uses JSON
-// field names for both formats, rejects unknown fields and accepts durations
-// such as "3s". Application-specific validation remains with the caller.
-func DecodeFile[T any](path string, defaults T) (T, error) {
-	result, err := decodeFile(path, defaults)
-	if err != nil {
-		var zero T
-		return zero, &DecodeError{cause: err}
-	}
-	return result, nil
-}
-
-// DecodeError keeps input values out of public diagnostics while preserving
-// errors.Is/As for explicitly handled underlying I/O and syntax errors.
-type DecodeError struct{ cause error }
-
-func (e *DecodeError) Error() string {
-	return "config: cannot decode file; check its path, format, field names and value types"
-}
-func (e *DecodeError) Unwrap() error { return e.cause }
-func decodeFile[T any](path string, defaults T) (T, error) {
-	var zero T
-	f, err := os.Open(path)
-	if err != nil {
-		return zero, err
-	}
-	defer f.Close()
-	data, err := io.ReadAll(io.LimitReader(f, (1<<20)+1))
-	if err != nil {
-		return zero, err
-	}
-	if len(data) > 1<<20 {
-		return zero, errors.New("config: file exceeds 1 MiB")
-	}
-	var value any
-	switch strings.ToLower(filepath.Ext(path)) {
-	case ".yaml", ".yml":
-		dec := yaml.NewDecoder(bytes.NewReader(data))
-		if err := dec.Decode(&value); err != nil {
-			return zero, err
-		}
-		var extra any
-		if err := dec.Decode(&extra); err != io.EOF {
-			return zero, errors.New("config: one YAML document required")
-		}
-	case ".json":
-		if err := apierrors.DecodeCatalogJSON(data, &value); err != nil {
-			return zero, err
-		}
-	default:
-		return zero, errors.New("config: expected .json, .yaml or .yml")
-	}
-	if _, ok := value.(map[string]any); !ok {
-		return zero, errors.New("config: root must be an object")
-	}
-	value, err = durations(value, reflect.TypeOf(defaults))
-	if err != nil {
-		return zero, err
-	}
-	encoded, err := json.Marshal(value)
-	if err != nil {
-		return zero, err
-	}
-	// Clone configuration without serializing borrowed json:"-" capabilities.
-	var result T
-	original, err := cloneConfiguration(reflect.ValueOf(&defaults).Elem(), 0)
-	if err != nil {
-		return zero, err
-	}
-	reflect.ValueOf(&result).Elem().Set(original)
-	dec := json.NewDecoder(bytes.NewReader(encoded))
-	dec.DisallowUnknownFields()
-	if err = dec.Decode(&result); err != nil {
-		return zero, err
-	}
-	return result, nil
-}
 func durations(v any, t reflect.Type) (any, error) {
 	if t == nil {
 		return v, nil
@@ -159,7 +75,7 @@ func LoadFile(path, prefix string) (Config, error) {
 	if err != nil {
 		return Config{}, err
 	}
-	return applyEnv(cfg, prefix)
+	return ApplyEnv(cfg, prefix)
 }

 // Reloader only accepts log.level changes. Static changes and invalid files
--- a/config/loader.go
+++ b/config/loader.go
@@ -0,0 +1,175 @@
+package config
+
+import (
+	"errors"
+	"io"
+	"os"
+	"path/filepath"
+	"reflect"
+	"strings"
+)
+
+const maxConfigBytes = 1 << 20
+const maxConfigDepth = 64
+const maxConfigNodes = 100000
+
+// Decoder must not retain or mutate input and must support concurrent calls
+// when its Loader is shared. It is trusted application code, not a sandbox.
+type Decoder interface {
+	Decode([]byte) (Document, error)
+}
+type DecoderFunc func([]byte) (Document, error)
+
+func (f DecoderFunc) Decode(data []byte) (Document, error) { return f(data) }
+
+// Loader owns an immutable per-instance decoder registry. No global registration.
+type Loader struct {
+	decoders map[string]Decoder
+	sealed   bool
+}
+type LoaderOption func(*Loader) error
+
+// WithDecoder adds a new extension; builtin/duplicate extensions cannot be replaced.
+func WithDecoder(extension string, decoder Decoder) LoaderOption {
+	return func(l *Loader) error {
+		if l == nil || l.decoders == nil || l.sealed {
+			return errors.New("config: decoder registry cannot be changed after construction")
+		}
+		ext := strings.ToLower(strings.TrimPrefix(extension, "."))
+		if ext == "" || strings.ContainsAny(ext, "./\\ \t\r\n") {
+			return errors.New("config: invalid decoder extension")
+		}
+		if decoder == nil {
+			return errors.New("config: nil decoder")
+		}
+		v := reflect.ValueOf(decoder)
+		if (v.Kind() == reflect.Pointer || v.Kind() == reflect.Func || v.Kind() == reflect.Map || v.Kind() == reflect.Slice || v.Kind() == reflect.Interface) && v.IsNil() {
+			return errors.New("config: nil decoder")
+		}
+		if _, exists := l.decoders[ext]; exists {
+			return errors.New("config: decoder extension already registered")
+		}
+		l.decoders[ext] = decoder
+		return nil
+	}
+}
+
+func NewLoader(options ...LoaderOption) (*Loader, error) {
+	l := &Loader{decoders: map[string]Decoder{"json": JSONDecoder{}, "yaml": YAMLDecoder{}, "yml": YAMLDecoder{}, "xml": XMLDecoder{}}}
+	for _, o := range options {
+		if o == nil {
+			return nil, errors.New("config: nil loader option")
+		}
+		if err := o(l); err != nil {
+			return nil, err
+		}
+	}
+	l.sealed = true
+	return l, nil
+}
+
+var defaultLoader, _ = NewLoader()
+
+func selectLoader(loaders []*Loader) (*Loader, error) {
+	if len(loaders) == 0 {
+		return defaultLoader, nil
+	}
+	if len(loaders) != 1 || loaders[0] == nil {
+		return nil, errors.New("config: expected one non-nil loader")
+	}
+	return loaders[0], nil
+}
+func (l *Loader) read(path string) (doc Document, err error) {
+	defer func() {
+		if err != nil {
+			var d *Error
+			if errors.As(err, &d) {
+				c := *d
+				c.File = path
+				err = &c
+			} else {
+				reason := "cannot read configuration file"
+				if errors.Is(err, os.ErrNotExist) {
+					reason = "configuration file does not exist"
+				} else if errors.Is(err, os.ErrPermission) {
+					reason = "permission denied reading configuration file"
+				}
+				err = &Error{File: path, Reason: reason, cause: err}
+			}
+		}
+	}()
+	decoder := l.decoders[strings.TrimPrefix(strings.ToLower(filepath.Ext(path)), ".")]
+	if decoder == nil {
+		return doc, &Error{Reason: "unsupported configuration format"}
+	}
+	info, e := os.Stat(path)
+	if e != nil {
+		return doc, e
+	}
+	if !info.Mode().IsRegular() {
+		return doc, &Error{Reason: "configuration must be a regular file"}
+	}
+	f, e := os.Open(path)
+	if e != nil {
+		return doc, e
+	}
+	defer f.Close()
+	info, e = f.Stat()
+	if e != nil {
+		return doc, e
+	}
+	if !info.Mode().IsRegular() {
+		return doc, &Error{Reason: "configuration must be a regular file"}
+	}
+	data, e := io.ReadAll(io.LimitReader(f, maxConfigBytes+1))
+	if e != nil {
+		return doc, e
+	}
+	if len(data) > maxConfigBytes {
+		return doc, &Error{Reason: "file exceeds 1 MiB"}
+	}
+	doc, err = decodeSafely(decoder, data)
+	if err != nil {
+		return doc, err
+	}
+	if _, ok := doc.Value.(map[string]any); !ok {
+		return doc, doc.diagnostic("", "root must be an object", nil)
+	}
+	return doc, nil
+}
+func decodeSafely(decoder Decoder, data []byte) (doc Document, err error) {
+	defer func() {
+		if recover() != nil {
+			err = &Error{Reason: "decoder panicked"}
+		}
+	}()
+	doc, err = decoder.Decode(data)
+	if err != nil {
+		var d *Error
+		if !errors.As(err, &d) {
+			err = &Error{Reason: "invalid configuration syntax", cause: err}
+		}
+	}
+	return
+}
+
+// DecodeFile overlays a bounded document onto independent defaults. With no
+// loader argument it accepts JSON/YAML/XML. It never opens dependencies.
+func DecodeFile[T any](path string, defaults T, loaders ...*Loader) (T, error) {
+	var zero T
+	l, err := selectLoader(loaders)
+	if err != nil {
+		return zero, err
+	}
+	doc, err := l.read(path)
+	if err != nil {
+		return zero, err
+	}
+	result, err := bindDocument(doc, defaults)
+	if err != nil {
+		d := validationError(err)
+		d.File = path
+		return zero, d
+	}
+	return result, nil
+}
--- a/config/loader_test.go
+++ b/config/loader_test.go
@@ -0,0 +1,397 @@
+package config
+
+import (
+	"encoding/json"
+	"errors"
+	"fmt"
+	"os"
+	"path/filepath"
+	"reflect"
+	"strings"
+	"sync"
+	"testing"
+	"time"
+)
+
+type loaderExample struct {
+	Server Config `json:"server"`
+	Upload struct {
+		MaxBytes int64 `json:"maxBytes" envDefault:"1024"`
+	} `json:"upload"`
+	Values   []int64 `json:"values"`
+	Optional *string `json:"optional"`
+	Enabled  bool    `json:"enabled"`
+	Dynamic  any     `json:"dynamic"`
+}
+
+func (c loaderExample) Validate() error {
+	if err := c.Server.Validate(); err != nil {
+		return AtField("server", err)
+	}
+	if c.Upload.MaxBytes < 0 {
+		return Invalid("upload.maxBytes", "must be nonnegative")
+	}
+	return nil
+}
+func noEnvironment(string) (string, bool) { return "", false }
+func configFile(t *testing.T, ext, raw string) string {
+	t.Helper()
+	path := filepath.Join(t.TempDir(), "service."+ext)
+	if err := os.WriteFile(path, []byte(raw), 0600); err != nil {
+		t.Fatal(err)
+	}
+	return path
+}
+
+func TestUnifiedFormatAndPrecedence(t *testing.T) {
+	formats := map[string]string{
+		"json": `{"server":{"http":{"readTimeout":"2s"}},"upload":{"maxBytes":7},"values":[9007199254740993],"optional":null,"enabled":true,"dynamic":{"id":9007199254740993}}`,
+		"yaml": "server:\n  http:\n    readTimeout: 2s\nupload:\n  maxBytes: 7\nvalues: [9007199254740993]\noptional: null\nenabled: true\ndynamic:\n  id: 9007199254740993\n",
+		"xml":  `<config><server><http><readTimeout>2s</readTimeout></http></server><upload><maxBytes>7</maxBytes></upload><values type="array"><item>9007199254740993</item></values><optional type="null"/><enabled>true</enabled><dynamic><id type="number">9007199254740993</id></dynamic></config>`,
+	}
+	var reference loaderExample
+	for _, ext := range []string{"json", "yaml", "xml"} {
+		t.Run(ext, func(t *testing.T) {
+			old := "old"
+			base := loaderExample{Server: Default(), Optional: &old}
+			cfg, err := LoadProject(configFile(t, ext, formats[ext]), base, EnvOptions{Prefix: "APP_", Lookup: func(key string) (string, bool) {
+				v, ok := map[string]string{"APP_UPLOAD_MAX_BYTES": "0", "APP_ENABLED": "false"}[key]
+				return v, ok
+			}})
+			if err != nil {
+				t.Fatal(err)
+			}
+			if cfg.Upload.MaxBytes != 0 || cfg.Enabled || cfg.Optional != nil || cfg.Values[0] != 9007199254740993 || cfg.Server.HTTP.ReadTimeout != 2*time.Second {
+				t.Fatal("values changed", cfg)
+			}
+			if cfg.Dynamic.(map[string]any)["id"] != json.Number("9007199254740993") {
+				t.Fatal("dynamic integer precision lost")
+			}
+			if ext == "json" {
+				reference = cfg
+			} else if !reflect.DeepEqual(reference, cfg) {
+				t.Fatal("format-dependent semantics")
+			}
+			if base.Optional == nil || *base.Optional != "old" {
+				t.Fatal("defaults mutated")
+			}
+		})
+	}
+	cfg, err := LoadProject("", loaderExample{Server: Default()}, EnvOptions{Lookup: noEnvironment})
+	if err != nil || cfg.Upload.MaxBytes != 1024 {
+		t.Fatal(cfg, err)
+	}
+}
+
+func TestConfigDiagnosticsAndCauses(t *testing.T) {
+	for _, tc := range []struct {
+		ext, body, field string
+		line             bool
+	}{
+		{"json", "{\n\"upload\": {\"maxBytes\":\"private-value\"}}", "upload.maxBytes", true},
+		{"yaml", "server:\n  http:\n    readTimeout: private-value", "server.http.readTimeout", true},
+		{"xml", "<config>\n<upload><maxBytes>private-value</maxBytes></upload></config>", "upload.maxBytes", true},
+		{"json", `{"upload":{"maxBytes":-1}}`, "upload.maxBytes", true},
+		{"yaml", "server:\n  http:\n    readTimeout: -1s", "server.http.readTimeout", true},
+		{"json", `{"upload":{"typo":3}}`, "upload.typo", true},
+	} {
+		t.Run(tc.ext+tc.field, func(t *testing.T) {
+			path := configFile(t, tc.ext, tc.body)
+			_, err := LoadProject(path, loaderExample{Server: Default()}, EnvOptions{Lookup: noEnvironment})
+			var d *Error
+			if !errors.As(err, &d) || d.File != path || d.Field != tc.field || d.Reason == "" || tc.line && d.Line < 1 {
+				t.Fatalf("missing location: %#v %v", d, err)
+			}
+			if strings.Contains(err.Error(), "private-value") {
+				t.Fatal("secret leaked", err)
+			}
+		})
+	}
+	path := filepath.Join(t.TempDir(), "missing.json")
+	_, err := LoadProject(path, loaderExample{}, EnvOptions{})
+	if !errors.Is(err, os.ErrNotExist) {
+		t.Fatal("I/O cause discarded", err)
+	}
+	_, err = DecodeFile(configFile(t, "json", `{"count":"private-value"}`), struct {
+		Count int `json:"count"`
+	}{})
+	var typed *json.UnmarshalTypeError
+	if !errors.As(err, &typed) {
+		t.Fatal("type cause discarded", err)
+	}
+	_, err = LoadProject(configFile(t, "yaml", "upload:\n  maxBytes: 7"), loaderExample{Server: Default()}, EnvOptions{Prefix: "APP_", Lookup: func(k string) (string, bool) { return "-1", k == "APP_UPLOAD_MAX_BYTES" }})
+	var d *Error
+	if !errors.As(err, &d) || d.Env != "APP_UPLOAD_MAX_BYTES" || d.Field != "upload.maxBytes" || d.File != "" || d.Line != 0 {
+		t.Fatal("environment validation wrongly blamed file", err)
+	}
+}
+
+func TestMalformedFormatsAndLimits(t *testing.T) {
+	for ext, bodies := range map[string][]string{
+		"json": {`{"enabled":true,"enabled":false}`, `{} {}`, `{"upload":`, `{"enabled":true,"Enabled":false}`, strings.Repeat(`{"a":`, 70) + `0` + strings.Repeat(`}`, 70)},
+		"yaml": {"enabled: true\nenabled: false", "---\n{}\n---\n{}", "a: &x [1]\nb: *x", "a:\n  <<: {}", "upload: [\n"},
+		"xml":  {`<!DOCTYPE config><config/>`, `<config>&private-value;</config>`, `<config/><config/>`, `<config xmlns="x"/>`, `<config type="" type=""/>`, `<config><enabled>true</enabled><enabled>false</enabled></config>`, `<config>text<enabled>true</enabled></config>`, `<config><values type="array"><bad>1</bad></values></config>`},
+	} {
+		for i, raw := range bodies {
+			t.Run(fmt.Sprintf("%s%d", ext, i), func(t *testing.T) {
+				_, err := LoadProject(configFile(t, ext, raw), loaderExample{Server: Default()}, EnvOptions{Lookup: noEnvironment})
+				if err == nil || strings.Contains(err.Error(), "private-value") {
+					t.Fatal(err)
+				}
+			})
+		}
+	}
+	if _, err := DecodeFile(configFile(t, "json", strings.Repeat(" ", maxConfigBytes+1)), loaderExample{}); err == nil {
+		t.Fatal("unbounded file")
+	}
+	if _, err := DecodeFile(configFile(t, "json", string([]byte{'{', '"', 0xff, '"', ':', '0', '}'})), loaderExample{}); err == nil {
+		t.Fatal("invalid UTF-8")
+	}
+}
+
+func TestDecoderRegistryAndConcurrentUse(t *testing.T) {
+	decoder := DecoderFunc(func([]byte) (Document, error) {
+		return Document{Value: map[string]any{"upload": map[string]any{"maxBytes": json.Number("42")}}}, nil
+	})
+	l, err := NewLoader(WithDecoder("custom", decoder))
+	if err != nil {
+		t.Fatal(err)
+	}
+	path := configFile(t, "custom", "ignored")
+	var wg sync.WaitGroup
+	for i := 0; i < 24; i++ {
+		wg.Add(1)
+		go func() {
+			defer wg.Done()
+			cfg, e := LoadProject(path, loaderExample{Server: Default()}, EnvOptions{Lookup: noEnvironment}, l)
+			if e != nil || cfg.Upload.MaxBytes != 42 {
+				t.Error(e)
+			}
+		}()
+	}
+	wg.Wait()
+	if _, err := DecodeFile(path, loaderExample{}); err == nil {
+		t.Fatal("decoder registration leaked globally")
+	}
+	for _, options := range [][]LoaderOption{{WithDecoder("json", decoder)}, {WithDecoder("x", decoder), WithDecoder("x", decoder)}, {WithDecoder("x", DecoderFunc(nil))}} {
+		if _, err = NewLoader(options...); err == nil {
+			t.Fatal("invalid registration")
+		}
+	}
+	l, _ = NewLoader(WithDecoder("panic", DecoderFunc(func([]byte) (Document, error) { panic("private-value") })))
+	_, err = DecodeFile(configFile(t, "panic", ""), loaderExample{}, l)
+	if err == nil || strings.Contains(err.Error(), "private-value") {
+		t.Fatal(err)
+	}
+	cycle := map[string]any{}
+	cycle["self"] = cycle
+	l, _ = NewLoader(WithDecoder("cycle", DecoderFunc(func([]byte) (Document, error) { return Document{Value: map[string]any{"dynamic": cycle}}, nil })))
+	if _, err = DecodeFile(configFile(t, "cycle", ""), loaderExample{}, l); err == nil {
+		t.Fatal("decoder bypassed traversal limit")
+	}
+}
+
+func TestUnifiedLoggerNormalization(t *testing.T) {
+	type project struct {
+		Server Config `json:"server"`
+	}
+	base := project{Server: Default()}
+	base.Server.Log.File = "old.log"
+	base.Server.Log.Rotation.Enabled = true
+	for _, full := range []bool{false, true} {
+		name := "GO_OMNI_LOG_OUTPUT"
+		if full {
+			name = "GO_OMNI_SERVER_LOG_OUTPUT"
+		}
+		cfg, err := LoadProject("", base, EnvOptions{Prefix: "GO_OMNI_", Empty: "ignore", Aliases: ServerEnvAliases("GO_OMNI_", "server"), Lookup: func(k string) (string, bool) { return "stdout", k == name }})
+		if err != nil || cfg.Server.Log.File != "" || cfg.Server.Log.Rotation.Enabled || base.Server.Log.File != "old.log" {
+			t.Fatal(cfg, err)
+		}
+	}
+}
+
+func FuzzConfigurationDecoders(f *testing.F) {
+	f.Add(uint8(0), []byte(`{"count":1}`))
+	f.Add(uint8(1), []byte("count: 1"))
+	f.Add(uint8(2), []byte("<config><count>1</count></config>"))
+	f.Fuzz(func(t *testing.T, format uint8, data []byte) {
+		if len(data) > 8192 {
+			data = data[:8192]
+		}
+		ds := []Decoder{JSONDecoder{}, YAMLDecoder{}, XMLDecoder{}}
+		doc, err := ds[int(format)%len(ds)].Decode(data)
+		if err == nil {
+			_, _ = bindDocument(doc, struct {
+				Count int `json:"count"`
+			}{})
+		}
+	})
+}
+
+func BenchmarkConfiguration(b *testing.B) {
+	for name, tc := range map[string]struct {
+		d   Decoder
+		raw string
+	}{"json": {JSONDecoder{}, `{"count":9007199254740993,"timeout":"5s","values":[1,2,3]}`}, "yaml": {YAMLDecoder{}, "count: 9007199254740993\ntimeout: 5s\nvalues: [1,2,3]"}, "xml": {XMLDecoder{}, `<config><count>9007199254740993</count><timeout>5s</timeout><values type="array"><item>1</item><item>2</item><item>3</item></values></config>`}} {
+		b.Run(name, func(b *testing.B) {
+			b.ReportAllocs()
+			raw := []byte(tc.raw)
+			for i := 0; i < b.N; i++ {
+				doc, err := tc.d.Decode(raw)
+				if err != nil {
+					b.Fatal(err)
+				}
+				_, err = bindDocument(doc, struct {
+					Count   int64         `json:"count"`
+					Timeout time.Duration `json:"timeout"`
+					Values  []int         `json:"values"`
+				}{})
+				if err != nil {
+					b.Fatal(err)
+				}
+			}
+		})
+	}
+}
+
+// Text-only scalars and embedded config fields use the same behavior in each format.
+type testText struct{ Value string }
+
+func (v *testText) UnmarshalText(data []byte) error { v.Value = string(data); return nil }
+func TestConfigScalarAndEmbedding(t *testing.T) {
+	type Fields struct {
+		Name string `json:"name"`
+	}
+	type C struct {
+		Fields
+		Nested Fields   `json:"nested"`
+		Scalar testText `json:"scalar"`
+		Bytes  []byte   `json:"bytes"`
+	}
+	cases := map[string]string{
+		"json": `{"name":"outer","nested":{"name":"inner"},"scalar":"text","bytes":"aGk="}`,
+		"yaml": "name: outer\nnested:\n  name: inner\nscalar: text\nbytes: aGk=\n",
+		"xml":  `<config><name>outer</name><nested><name>inner</name></nested><scalar>text</scalar><bytes>aGk=</bytes></config>`,
+	}
+	for ext, data := range cases {
+		t.Run(ext, func(t *testing.T) {
+			path := filepath.Join(t.TempDir(), "config."+ext)
+			os.WriteFile(path, []byte(data), 0600)
+			got, err := DecodeFile(path, &C{})
+			if err != nil {
+				t.Fatal(err)
+			}
+			if got.Name != "outer" || got.Nested.Name != "inner" || got.Scalar.Value != "text" || string(got.Bytes) != "hi" {
+				t.Fatal(got)
+			}
+		})
+	}
+	type Tagged struct {
+		Fields `json:"nested"`
+	}
+	doc, _ := (JSONDecoder{}).Decode([]byte(`{"name":"wrong"}`))
+	if _, err := bindDocument(doc, Tagged{}); err == nil {
+		t.Fatal("tagged embed incorrectly flattened")
+	}
+}
+func TestConfigDefaultsIsolationAndEmptyValues(t *testing.T) {
+	type Child struct {
+		Name string `json:"name"`
+	}
+	type C struct {
+		Child   *Child            `json:"child"`
+		Items   []int             `json:"items"`
+		Labels  map[string]string `json:"labels"`
+		Enabled bool              `json:"enabled"`
+	}
+	base := C{Child: &Child{Name: "old"}, Items: []int{1}, Labels: map[string]string{"old": "yes"}, Enabled: true}
+	doc, _ := (JSONDecoder{}).Decode([]byte(`{"child":{"name":"new"},"labels":{"new":"yes"},"items":[],"enabled":false}`))
+	got, err := bindDocument(doc, base)
+	if err != nil {
+		t.Fatal(err)
+	}
+	if got.Child.Name != "new" || got.Items == nil || len(got.Items) != 0 || got.Enabled {
+		t.Fatal(got)
+	}
+	if base.Child.Name != "old" || len(base.Items) != 1 || len(base.Labels) != 1 {
+		t.Fatal("mutated defaults")
+	}
+	bad, _ := (JSONDecoder{}).Decode([]byte(`{"child":{"name":"changed"},"items":"bad"}`))
+	if _, err := bindDocument(bad, base); err == nil {
+		t.Fatal("invalid input accepted")
+	}
+	if base.Child.Name != "old" {
+		t.Fatal("failed load changed default pointer")
+	}
+	null, _ := (JSONDecoder{}).Decode([]byte(`{"child":null,"items":null,"labels":null,"enabled":null}`))
+	got, err = bindDocument(null, base)
+	if err != nil || got.Child != nil || got.Items != nil || got.Labels != nil || !got.Enabled {
+		t.Fatal(got, err)
+	}
+}
+func TestDefaultStageDoesNotReadEnvironment(t *testing.T) {
+	reads := 0
+	type C struct {
+		Value int `json:"value" envDefault:"3"`
+	}
+	got, err := LoadProject("", C{}, EnvOptions{Lookup: func(string) (string, bool) { reads++; return "", false }})
+	if err != nil || got.Value != 3 || reads != 1 {
+		t.Fatal(got, err, reads)
+	}
+	d := locateError(Invalid("servers[0].timeout", "must be positive"), "a.json", Document{}, map[string]string{"servers": "APP_SERVERS"})
+	if d.Env != "APP_SERVERS" || d.File != "" {
+		t.Fatal(d)
+	}
+}
+
+func TestDecoderRegistryFrozen(t *testing.T) {
+	l, err := NewLoader()
+	if err != nil {
+		t.Fatal(err)
+	}
+	if err = WithDecoder("extra", JSONDecoder{})(l); err == nil {
+		t.Fatal("mutable registry")
+	}
+}
+func BenchmarkConfigurationStartup(b *testing.B) {
+	path := filepath.Join(b.TempDir(), "app.json")
+	if err := os.WriteFile(path, []byte(`{"server":{"http":{"readTimeout":"2s"}},"upload":{"maxBytes":4096}}`), 0600); err != nil {
+		b.Fatal(err)
+	}
+	options := EnvOptions{Prefix: "BENCH_", Lookup: func(name string) (string, bool) {
+		if name == "BENCH_UPLOAD_MAX_BYTES" {
+			return "8192", true
+		}
+		return "", false
+	}}
+	defaults := loaderExample{Server: Default()}
+	b.ReportAllocs()
+	b.ResetTimer()
+	for i := 0; i < b.N; i++ {
+		if _, err := LoadProject(path, defaults, options); err != nil {
+			b.Fatal(err)
+		}
+	}
+}
+func BenchmarkConfigurationLarge(b *testing.B) {
+	type Entry struct {
+		Timeout time.Duration `json:"timeout"`
+		Count   int           `json:"count"`
+	}
+	type Large struct {
+		Entries []Entry `json:"entries"`
+	}
+	raw := []byte(`{"entries":[` + strings.TrimSuffix(strings.Repeat(`{"timeout":"3s","count":10},`, 1000), ",") + `]}`)
+	b.SetBytes(int64(len(raw)))
+	b.ReportAllocs()
+	b.ResetTimer()
+	for i := 0; i < b.N; i++ {
+		doc, err := (JSONDecoder{}).Decode(raw)
+		if err != nil {
+			b.Fatal(err)
+		}
+		if _, err = bindDocument(doc, Large{}); err != nil {
+			b.Fatal(err)
+		}
+	}
+}
--- a/config/project.go
+++ b/config/project.go
@@ -7,6 +7,7 @@ import (
 	"errors"
 	"fmt"
 	apierrors "git.yuntuo.hk/k2safe/go-omni/errors"
+	"git.yuntuo.hk/k2safe/go-omni/logx"
 	"math"
 	"os"
 	"reflect"
@@ -23,6 +24,9 @@ type EnvOptions struct {
 	Prefix string
 	Empty  string
 	Lookup func(string) (string, bool)
+	// Aliases maps canonical absolute environment names to ordered fallback names.
+	// A present canonical value wins, including an explicit empty value.
+	Aliases map[string][]string
 }

 // ApplyDefaults applies envDefault tags to zero fields before file overlays.
@@ -31,30 +35,114 @@ func ApplyDefaults[T any](base T) (T, error) { return projectOverlay(base, EnvOp
 // LoadProject applies code/tag defaults, a strict optional file, environment,
 // then the project's Validate method, before any logger or dependency is opened.
 // envDefault is only applied to zero-valued defaults before reading the file.
-func LoadProject[T any](path string, defaults T, options EnvOptions) (T, error) {
+func LoadProject[T any](path string, defaults T, options EnvOptions, loaders ...*Loader) (T, error) {
 	var zero T
+	loader, err := selectLoader(loaders)
+	if err != nil {
+		return zero, err
+	}
 	cfg, err := projectOverlay(defaults, options, true)
 	if err != nil {
 		return zero, err
 	}
+	var doc Document
 	if path != "" {
-		cfg, err = DecodeFile(path, cfg)
+		doc, err = loader.read(path)
 		if err != nil {
-			return zero, errors.New("config: cannot decode file; check its path, format, field names and value types")
+			return zero, err
 		}
+		cfg, err = bindDocument(doc, cfg)
+		if err != nil {
+			return zero, locateError(err, path, doc, nil)
+		}
+	} else {
+		value, e := cloneConfiguration(reflect.ValueOf(&cfg).Elem(), 0)
+		if e != nil {
+			return zero, &Error{Reason: "cannot clone defaults", cause: e}
+		}
+		cfg = value.Interface().(T)
 	}
-	cfg, err = OverlayEnv(cfg, options)
+	origins := map[string]string{}
+	cfg, err = projectOverlay(cfg, options, false, origins)
 	if err != nil {
 		return zero, err
 	}
+	normalizeProject(reflect.ValueOf(&cfg).Elem(), "", origins, 0)
 	if valid, ok := any(&cfg).(interface{ Validate() error }); ok {
 		if err = valid.Validate(); err != nil {
-			return zero, err
+			return zero, locateError(err, path, doc, origins)
 		}
 	}
 	return cfg, nil
 }

+func locateError(err error, path string, doc Document, origins map[string]string) *Error {
+	d := validationError(err)
+	field := d.Field
+	for field != "" && origins[field] == "" {
+		index := strings.LastIndexAny(field, ".[")
+		if index < 0 {
+			field = ""
+		} else {
+			field = field[:index]
+		}
+	}
+	if env := origins[field]; env != "" {
+		d.Env = env
+		d.File = ""
+		d.Line = 0
+		d.Column = 0
+		return d
+	}
+	d.File = path
+	if d.Line == 0 {
+		p := doc.Positions[d.Field]
+		d.Line = p.Line
+		d.Column = p.Column
+	}
+	return d
+}
+
+// Framework-owned normalization stays inside the common pipeline. Explicit
+// environment stream selection clears a file profile unless a file override
+// was also provided; project code never needs to repeat this rule.
+func normalizeProject(v reflect.Value, path string, origins map[string]string, depth int) {
+	if depth > 32 {
+		return
+	}
+	if v.Kind() == reflect.Pointer {
+		if v.IsNil() {
+			return
+		}
+		v = v.Elem()
+	}
+	if v.Kind() != reflect.Struct {
+		return
+	}
+	if v.Type() == reflect.TypeOf(Config{}) && v.CanAddr() {
+		c := v.Addr().Interface().(*Config)
+		if origins[joinField(path, "log.output")] != "" && c.Log.Output != "" && (origins[joinField(path, "log.file")] == "" || c.Log.File == "") {
+			c.Log.File = ""
+			c.Log.Rotation = logx.RotationConfig{}
+		}
+		return
+	}
+	for i := 0; i < v.NumField(); i++ {
+		f := v.Type().Field(i)
+		if f.PkgPath != "" {
+			continue
+		}
+		name := strings.Split(f.Tag.Get("json"), ",")[0]
+		if name == "-" {
+			continue
+		}
+		if name == "" {
+			name = f.Name
+		}
+		normalizeProject(v.Field(i), joinField(path, name), origins, depth+1)
+	}
+}
+
 // OverlayEnv overlays the entire project struct without mutating the input.
 // Tags: env:"CUSTOM_NAME,required,secret,empty=reject"; env:"-" excludes a
 // subtree. required means nonempty string/non-nil pointer or collection; false
@@ -67,7 +155,7 @@ func OverlayEnv[T any](base T, options EnvOptions) (T, error) {
 var textType = reflect.TypeOf((*encoding.TextUnmarshaler)(nil)).Elem()
 var durationType = reflect.TypeOf(time.Duration(0))

-func projectOverlay[T any](base T, options EnvOptions, defaults bool) (T, error) {
+func projectOverlay[T any](base T, options EnvOptions, defaults bool, sourceMaps ...map[string]string) (T, error) {
 	var zero T
 	if options.Lookup == nil {
 		options.Lookup = os.LookupEnv
@@ -85,8 +173,8 @@ func projectOverlay[T any](base T, options EnvOptions, defaults bool) (T, error)
 	result := reflect.New(v.Type()).Elem()
 	result.Set(v)
 	seen := map[string]bool{}
-	var walk func(reflect.Value, string, int) error
-	walk = func(value reflect.Value, prefix string, depth int) error {
+	var walk func(reflect.Value, string, string, int) error
+	walk = func(value reflect.Value, prefix, path string, depth int) error {
 		if depth > 32 {
 			return errors.New("config: nesting exceeds 32")
 		}
@@ -107,6 +195,7 @@ func projectOverlay[T any](base T, options EnvOptions, defaults bool) (T, error)
 			if jsonName == "" {
 				jsonName = field.Name
 			}
+			fieldPath := joinField(path, jsonName)
 			key := prefix + envName(jsonName)
 			if tag[0] != "" {
 				key = tag[0]
@@ -128,7 +217,7 @@ func projectOverlay[T any](base T, options EnvOptions, defaults bool) (T, error)
 				}
 			}
 			if dst.Kind() == reflect.Struct && !dst.Addr().Type().Implements(textType) {
-				if err := walk(dst, key+"_", depth+1); err != nil {
+				if err := walk(dst, key+"_", fieldPath, depth+1); err != nil {
 					return err
 				}
 				continue
@@ -139,14 +228,14 @@ func projectOverlay[T any](base T, options EnvOptions, defaults bool) (T, error)
 				if !dst.IsNil() {
 					child.Elem().Set(dst.Elem())
 				}
-				if err := walk(child.Elem(), key+"_", depth+1); err != nil {
+				if err := walk(child.Elem(), key+"_", fieldPath, depth+1); err != nil {
 					return err
 				}
 				if !dst.IsNil() || !child.Elem().IsZero() {
 					dst.Set(child)
 				}
 				if required && !defaults && dst.IsNil() {
-					return fmt.Errorf("config: %s is required", key)
+					return &Error{Env: key, Field: fieldPath, Reason: "is required"}
 				}
 				continue
 			}
@@ -161,14 +250,27 @@ func projectOverlay[T any](base T, options EnvOptions, defaults bool) (T, error)
 				return fmt.Errorf("config: duplicate environment key %s", key)
 			}
 			seen[key] = true
-			raw, present := options.Lookup(key)
+			var raw string
+			var present bool
+			if !defaults {
+				raw, present = options.Lookup(key)
+			}
+			selectedKey := key
+			if !present && !defaults {
+				for _, alias := range options.Aliases[key] {
+					if raw, present = options.Lookup(alias); present {
+						selectedKey = alias
+						break
+					}
+				}
+			}
 			if defaults {
 				raw, present = field.Tag.Lookup("envDefault")
 				present = present && dst.IsZero()
 			}
 			if present && raw == "" && !defaults {
 				if empty == "reject" {
-					return fmt.Errorf("config: %s must not be empty", key)
+					return &Error{Env: selectedKey, Field: fieldPath, Reason: "must not be empty"}
 				}
 				if empty == "ignore" {
 					present = false
@@ -177,17 +279,24 @@ func projectOverlay[T any](base T, options EnvOptions, defaults bool) (T, error)
 			if present {
 				parsed := reflect.New(dst.Type()).Elem()
 				if err := parseEnvValue(parsed, raw); err != nil {
-					return fmt.Errorf("config: %s must be a valid %s", key, dst.Type())
+					origin := selectedKey
+					if defaults {
+						origin = ""
+					}
+					return &Error{Env: origin, Field: fieldPath, Reason: "expected a valid " + dst.Type().String(), cause: err}
 				}
 				dst.Set(parsed)
+				if !defaults && len(sourceMaps) > 0 {
+					sourceMaps[0][fieldPath] = selectedKey
+				}
 			}
 			if required && !defaults && emptyRequired(dst) {
-				return fmt.Errorf("config: %s is required", key)
+				return &Error{Env: key, Field: fieldPath, Reason: "is required"}
 			}
 		}
 		return nil
 	}
-	if err := walk(result, options.Prefix, 0); err != nil {
+	if err := walk(result, options.Prefix, "", 0); err != nil {
 		return zero, err
 	}
 	return result.Interface().(T), nil
--- a/copyx/benchmark_test.go
+++ b/copyx/benchmark_test.go
@@ -0,0 +1,117 @@
+package copyx_test
+
+import (
+	"errors"
+	"fmt"
+	"testing"
+
+	"git.yuntuo.hk/k2safe/go-omni/copyx"
+)
+
+func BenchmarkScenarios(b *testing.B) {
+	type request struct {
+		Name   string
+		Count  int64
+		Active bool
+	}
+	type result struct {
+		Label  string
+		Count  int64
+		Active bool
+	}
+	source := request{"sample", 9007199254740993, true}
+	option := copyx.WithFieldNames[request, result](map[string]string{"Name": "Label"})
+	copier, err := copyx.New(option)
+	if err != nil {
+		b.Fatal(err)
+	}
+	for _, reuse := range []bool{false, true} {
+		b.Run(fmt.Sprintf("struct/reuse%t", reuse), func(b *testing.B) {
+			b.ReportAllocs()
+			for i := 0; i < b.N; i++ {
+				var target result
+				var err error
+				if reuse {
+					err = copier.Copy(&target, source)
+				} else {
+					err = copyx.Copy(&target, source, option)
+				}
+				if err != nil {
+					b.Fatal(err)
+				}
+			}
+		})
+	}
+	deep, _ := copyx.New(copyx.WithDeepCopy())
+	b.Run("bytes64KiB", func(b *testing.B) {
+		src := make([]byte, 64<<10)
+		b.SetBytes(int64(len(src)))
+		b.ReportAllocs()
+		b.ResetTimer()
+		for i := 0; i < b.N; i++ {
+			var dst []byte
+			if err := deep.Copy(&dst, src); err != nil {
+				b.Fatal(err)
+			}
+		}
+	})
+	src := map[string][]int{}
+	for i := 0; i < 100; i++ {
+		src[fmt.Sprint(i)] = []int{1, 2, 3}
+	}
+	b.Run("map100", func(b *testing.B) {
+		b.ReportAllocs()
+		for i := 0; i < b.N; i++ {
+			var dst map[string][]int
+			if err := deep.Copy(&dst, src); err != nil {
+				b.Fatal(err)
+			}
+		}
+	})
+	cycle := &detail{Values: []int{1, 2, 3}}
+	cycle.Next = cycle
+	b.Run("cycle", func(b *testing.B) {
+		b.ReportAllocs()
+		for i := 0; i < b.N; i++ {
+			var dst *detail
+			if err := deep.Copy(&dst, cycle); err != nil {
+				b.Fatal(err)
+			}
+		}
+	})
+	b.Run("parallelCycle", func(b *testing.B) {
+		b.ReportAllocs()
+		b.RunParallel(func(pb *testing.PB) {
+			for pb.Next() {
+				var dst *detail
+				if err := deep.Copy(&dst, cycle); err != nil {
+					b.Error(err)
+					return
+				}
+			}
+		})
+	})
+	for _, fresh := range []bool{false, true} {
+		b.Run(fmt.Sprintf("converter/fresh%t", fresh), func(b *testing.B) {
+			c, err := copyx.New(copyx.WithDeepCopy(), copyx.WithConverter(func(v []int) ([]int, error) {
+				if fresh {
+					return append([]int(nil), v...), nil
+				}
+				return v, nil
+			}))
+			if err != nil {
+				b.Fatal(err)
+			}
+			src := []int{1, 2, 3}
+			b.ReportAllocs()
+			b.ResetTimer()
+			for i := 0; i < b.N; i++ {
+				var dst []int
+				err := c.Copy(&dst, src)
+				if fresh && err != nil || !fresh && !errors.Is(err, copyx.ErrSharedReference) {
+					b.Fatal(err)
+				}
+			}
+		})
+	}
+}
--- a/copyx/copy.go
+++ b/copyx/copy.go
@@ -0,0 +1,537 @@
+package copyx
+
+import (
+	"errors"
+	"fmt"
+	"reflect"
+	"runtime"
+	"sort"
+	"sync"
+)
+
+var (
+	ErrType            = errors.New("copyx: incompatible types")
+	ErrNil             = errors.New("copyx: nil cannot fill a non-nullable target")
+	ErrField           = errors.New("copyx: unmatched field")
+	ErrUnsupported     = errors.New("copyx: unsupported value; provide an explicit data converter")
+	ErrSharedReference = errors.New("copyx: deep copy retains a mutable source reference")
+	ErrLimit           = errors.New("copyx: traversal limit exceeded")
+)
+
+// Error describes a field/index path without recording the source value.
+type Error struct {
+	Path  string
+	Cause error
+}
+
+func (e *Error) Error() string        { return e.Path + ": " + e.Cause.Error() }
+func (e *Error) Unwrap() error        { return e.Cause }
+func at(path string, err error) error { return &Error{Path: path, Cause: err} }
+
+func Copy(target, source any, options ...Option) error {
+	c, err := New(options...)
+	if err != nil {
+		return err
+	}
+	return c.Copy(target, source)
+}
+
+// Clone always makes a deep copy. Nil and empty collections stay distinct.
+func Clone[T any](source T, options ...Option) (T, error) {
+	var target T
+	options = append(append([]Option(nil), options...), WithDeepCopy())
+	err := Copy(&target, source, options...)
+	return target, err
+}
+
+// Copy stages the complete result and only assigns target on success. User
+// converter side effects (including mutation of source) cannot be rolled back.
+// Caller must synchronize concurrent access to source and target themselves.
+func (c *Copier) Copy(target, source any) error {
+	// Alias indexes contain addresses only. Keep the original graph alive until
+	// validation and commit finish so the GC cannot recycle any indexed address.
+	defer func() { runtime.KeepAlive(source) }()
+	if c == nil {
+		return errors.New("copyx: nil Copier")
+	}
+	dst := reflect.ValueOf(target)
+	if !dst.IsValid() || dst.Kind() != reflect.Pointer || dst.IsNil() {
+		return errors.New("copyx: target must be a non-nil pointer")
+	}
+	src := reflect.ValueOf(source)
+	s := state{options: &c.options, seen: map[visit]reflect.Value{}}
+	if c.options.deep {
+		var err error
+		s.graph, err = sourceGraph(src)
+		if err != nil {
+			return err
+		}
+		if src.IsValid() && src.Kind() == reflect.Pointer && !src.IsNil() && dst.Elem().Kind() == reflect.Struct {
+			id := identity(src)
+			s.valueRoot = &id
+		}
+	}
+	out, err := s.walk(src, dst.Elem(), dst.Elem().Type(), "$", 0)
+	if err != nil {
+		return err
+	}
+	if s.graph != nil {
+		if err = s.graph.audit(out); err != nil {
+			return err
+		}
+	}
+	dst.Elem().Set(out)
+	return nil
+}
+
+type visit struct {
+	reference
+	target reflect.Type
+}
+type state struct {
+	options   *settings
+	seen      map[visit]reflect.Value
+	graph     *graph
+	nodes     int
+	allocated uint64
+	valueRoot *reference
+}
+
+func (s *state) reserve(count int, size uintptr, path string) error {
+	if count < 0 || (count > 0 && uint64(size) > maxCopyBytes/uint64(count)) {
+		return at(path, ErrLimit)
+	}
+	s.allocated += uint64(count) * uint64(size)
+	if s.allocated > maxCopyBytes {
+		return at(path, ErrLimit)
+	}
+	return nil
+}
+
+func nullable(k reflect.Kind) bool {
+	switch k {
+	case reflect.Pointer, reflect.Map, reflect.Slice, reflect.Interface, reflect.Func, reflect.Chan:
+		return true
+	}
+	return false
+}
+func baseValue(base reflect.Value, t reflect.Type) reflect.Value {
+	if base.IsValid() && base.Type() == t {
+		return base
+	}
+	return reflect.Zero(t)
+}
+func (s *state) walk(src, base reflect.Value, t reflect.Type, path string, depth int) (reflect.Value, error) {
+	s.nodes++
+	if depth > maxDepth || s.nodes > maxNodes {
+		return reflect.Value{}, at(path, ErrLimit)
+	}
+	base = baseValue(base, t)
+	if !shallowSafe(t) {
+		return reflect.Value{}, at(path, ErrUnsupported)
+	}
+	if src.IsValid() && !src.CanInterface() {
+		return reflect.Value{}, at(path, ErrUnsupported)
+	}
+	// Exact converters also receive typed nils and zeros. No method calls,
+	// Scanner/Valuer invocation or implicit numeric conversion is attempted.
+	if src.IsValid() {
+		if convert, ok := s.options.converters[pair{src.Type(), t}]; ok {
+			out, err := convert(src)
+			if err != nil {
+				return reflect.Value{}, at(path, err)
+			}
+			if s.graph != nil {
+				if err = s.graph.audit(out); err != nil {
+					return reflect.Value{}, at(path, err)
+				}
+			}
+			return out, nil
+		}
+	}
+	if !src.IsValid() || (nullable(src.Kind()) && src.IsNil()) {
+		if src.IsValid() && !s.nilCompatible(src.Type(), t, map[pair]bool{}) {
+			return reflect.Value{}, at(path, ErrType)
+		}
+		if s.options.nilPolicy == NilSkip {
+			return base, nil
+		}
+		if nullable(t.Kind()) || s.options.nilPolicy == NilZero {
+			return reflect.Zero(t), nil
+		}
+		return reflect.Value{}, at(path, ErrNil)
+	}
+	if s.options.skipZero && src.IsZero() {
+		if !s.nilCompatible(src.Type(), t, map[pair]bool{}) {
+			return reflect.Value{}, at(path, ErrType)
+		}
+		return base, nil
+	}
+	if src.Type() == t && len(s.options.converters) == 0 && len(s.options.fields) == 0 && !s.options.skipZero && s.options.nilPolicy != NilSkip {
+		if !s.options.deep || simpleValue(t) {
+			return src, nil
+		}
+	}
+	if src.Kind() == reflect.Interface {
+		return s.walk(src.Elem(), base, t, path, depth+1)
+	}
+	if t.Kind() == reflect.Interface {
+		if !src.Type().Implements(t) {
+			return reflect.Value{}, at(path, ErrType)
+		}
+		out, err := s.walk(src, reflect.Value{}, src.Type(), path, depth+1)
+		if err != nil {
+			return reflect.Value{}, err
+		}
+		v := reflect.New(t).Elem()
+		v.Set(out)
+		return v, nil
+	}
+	if s.options.deep && forbidden(t) {
+		return reflect.Value{}, at(path, ErrUnsupported)
+	}
+	if src.Kind() == reflect.Pointer && t.Kind() != reflect.Pointer {
+		return s.walk(src.Elem(), base, t, path, depth+1)
+	}
+	if t.Kind() == reflect.Pointer {
+		if !s.options.deep && src.Type() == t {
+			return src, nil
+		}
+		if src.Kind() == reflect.Pointer {
+			key := visit{identity(src), t}
+			if s.valueRoot != nil && key.reference == *s.valueRoot {
+				return reflect.Value{}, at(path, fmt.Errorf("%w: cyclic root must retain its pointer; use Clone(source) or Copy(&targetPointer, source)", ErrUnsupported))
+			}
+			if prior, ok := s.seen[key]; ok {
+				return prior, nil
+			}
+		}
+		if err := s.reserve(1, t.Elem().Size(), path); err != nil {
+			return reflect.Value{}, err
+		}
+		out := reflect.New(t.Elem())
+		if out.Type() != t {
+			out = out.Convert(t)
+		}
+		if src.Kind() == reflect.Pointer {
+			key := visit{identity(src), t}
+			s.seen[key] = out
+			src = src.Elem()
+		}
+		var childBase reflect.Value
+		if !base.IsNil() {
+			childBase = base.Elem()
+		}
+		value, err := s.walk(src, childBase, t.Elem(), path, depth+1)
+		if err != nil {
+			return reflect.Value{}, err
+		}
+		out.Elem().Set(value)
+		return out, nil
+	}
+	if src.Kind() != t.Kind() {
+		return reflect.Value{}, at(path, fmt.Errorf("%w: %s -> %s", ErrType, src.Type(), t))
+	}
+	if t == timeType && src.Type() == t {
+		return src, nil
+	}
+	switch t.Kind() {
+	case reflect.Struct:
+		return s.structure(src, base, t, path, depth)
+	case reflect.Slice:
+		if !s.options.deep && src.Type() == t {
+			return src, nil
+		}
+		key := visit{identity(src), t}
+		if prior, ok := s.seen[key]; ok {
+			return prior, nil
+		}
+		if err := s.reserve(src.Len(), t.Elem().Size(), path); err != nil {
+			return reflect.Value{}, err
+		}
+		out := reflect.MakeSlice(t, src.Len(), src.Len())
+		s.seen[key] = out
+		if src.Type() == t && len(s.options.converters) == 0 && len(s.options.fields) == 0 && simpleValue(t.Elem()) {
+			reflect.Copy(out, src)
+			return out, nil
+		}
+		for i := 0; i < src.Len(); i++ {
+			v, err := s.walk(src.Index(i), reflect.Value{}, t.Elem(), fmt.Sprintf("%s[%d]", path, i), depth+1)
+			if err != nil {
+				return reflect.Value{}, err
+			}
+			out.Index(i).Set(v)
+		}
+		return out, nil
+	case reflect.Array:
+		if src.Len() != t.Len() {
+			return reflect.Value{}, at(path, ErrType)
+		}
+		if err := s.reserve(1, t.Size(), path); err != nil {
+			return reflect.Value{}, err
+		}
+		out := reflect.New(t).Elem()
+		for i := 0; i < src.Len(); i++ {
+			v, err := s.walk(src.Index(i), base.Index(i), t.Elem(), fmt.Sprintf("%s[%d]", path, i), depth+1)
+			if err != nil {
+				return reflect.Value{}, err
+			}
+			out.Index(i).Set(v)
+		}
+		return out, nil
+	case reflect.Map:
+		if !s.options.deep && src.Type() == t {
+			return src, nil
+		}
+		key := visit{identity(src), t}
+		if prior, ok := s.seen[key]; ok {
+			return prior, nil
+		}
+		if err := s.reserve(src.Len(), t.Key().Size()+t.Elem().Size()+32, path); err != nil {
+			return reflect.Value{}, err
+		}
+		out := reflect.MakeMapWithSize(t, src.Len())
+		s.seen[key] = out
+		it := src.MapRange()
+		for it.Next() {
+			k, err := s.walk(it.Key(), reflect.Value{}, t.Key(), path+"[key]", depth+1)
+			if err != nil {
+				return reflect.Value{}, err
+			}
+			if !k.Comparable() {
+				return reflect.Value{}, at(path+"[key]", ErrType)
+			}
+			if out.MapIndex(k).IsValid() {
+				return reflect.Value{}, at(path+"[key]", errors.New("copyx: key conversion collision"))
+			}
+			v, err := s.walk(it.Value(), reflect.Value{}, t.Elem(), path+"[value]", depth+1)
+			if err != nil {
+				return reflect.Value{}, err
+			}
+			out.SetMapIndex(k, v)
+		}
+		return out, nil
+	case reflect.Func, reflect.Chan, reflect.UnsafePointer:
+		if s.options.deep {
+			return reflect.Value{}, at(path, ErrUnsupported)
+		}
+	}
+	if src.Type() != t {
+		return reflect.Value{}, at(path, fmt.Errorf("%w: %s -> %s", ErrType, src.Type(), t))
+	}
+	return src, nil
+}
+
+var fieldTypes sync.Map
+
+func exportedFields(t reflect.Type) map[string]reflect.StructField {
+	if known, ok := fieldTypes.Load(t); ok {
+		return known.(map[string]reflect.StructField)
+	}
+	out := map[string]reflect.StructField{}
+	for _, f := range reflect.VisibleFields(t) {
+		if f.PkgPath != "" {
+			continue
+		}
+		kind := f.Type.Kind()
+		if kind == reflect.Pointer {
+			kind = f.Type.Elem().Kind()
+		}
+		if f.Anonymous && kind == reflect.Struct {
+			continue
+		}
+		out[f.Name] = f
+	}
+	actual, _ := fieldTypes.LoadOrStore(t, out)
+	return actual.(map[string]reflect.StructField)
+}
+
+func (s *state) nilCompatible(from, to reflect.Type, seen map[pair]bool) bool {
+	key := pair{from, to}
+	if seen[key] {
+		return true
+	}
+	seen[key] = true
+	if from == to {
+		return true
+	}
+	if _, ok := s.options.converters[key]; ok {
+		return true
+	}
+	if to.Kind() == reflect.Interface {
+		return from.Implements(to)
+	}
+	if from.Kind() == reflect.Pointer {
+		return s.nilCompatible(from.Elem(), to, seen)
+	}
+	if to.Kind() == reflect.Pointer {
+		return s.nilCompatible(from, to.Elem(), seen)
+	}
+	if from.Kind() != to.Kind() {
+		return false
+	}
+	switch from.Kind() {
+	case reflect.Struct:
+		// Nil must not hide a structurally incompatible type pair. There are no
+		// field values to visit, but coverage and conversion types still apply.
+		for i := 0; i < to.NumField(); i++ {
+			if to.Field(i).PkgPath != "" {
+				return false
+			}
+		}
+		sources, targets := exportedFields(from), exportedFields(to)
+		rules := s.options.fields[key]
+		if rules == nil {
+			rules = &fields{}
+		}
+		reverse, used := map[string]string{}, map[string]bool{}
+		for a, b := range rules.names {
+			reverse[b] = a
+		}
+		for name, target := range targets {
+			if rules.ignoreTarget[name] {
+				continue
+			}
+			srcName := name
+			if renamed, ok := reverse[name]; ok {
+				srcName = renamed
+			}
+			source, ok := sources[srcName]
+			if !ok || rules.ignoreSource[srcName] || !s.nilCompatible(source.Type, target.Type, seen) {
+				return false
+			}
+			used[srcName] = true
+		}
+		if s.options.strict {
+			for name := range sources {
+				if !used[name] && !rules.ignoreSource[name] {
+					return false
+				}
+			}
+		}
+		return true
+	case reflect.Slice:
+		return s.nilCompatible(from.Elem(), to.Elem(), seen)
+	case reflect.Map:
+		return s.nilCompatible(from.Key(), to.Key(), seen) && s.nilCompatible(from.Elem(), to.Elem(), seen)
+	case reflect.Array:
+		return from.Len() == to.Len() && s.nilCompatible(from.Elem(), to.Elem(), seen)
+	}
+	return false
+}
+func fieldValue(v reflect.Value, index []int) (reflect.Value, bool) {
+	for _, i := range index {
+		if v.Kind() == reflect.Pointer {
+			if v.IsNil() {
+				return reflect.Value{}, false
+			}
+			v = v.Elem()
+		}
+		v = v.Field(i)
+	}
+	return v, true
+}
+func setField(v reflect.Value, index []int, value reflect.Value) error {
+	for j, i := range index {
+		field := v.Field(i)
+		if !field.CanSet() {
+			return ErrUnsupported
+		}
+		if j == len(index)-1 {
+			field.Set(value)
+			return nil
+		}
+		if field.Kind() == reflect.Pointer {
+			// Detach embedded destination pointers before editing promoted fields.
+			fresh := reflect.New(field.Type().Elem())
+			if !field.IsNil() {
+				fresh.Elem().Set(field.Elem())
+			}
+			field.Set(fresh)
+			v = fresh.Elem()
+		} else {
+			v = field
+		}
+	}
+	return nil
+}
+func (s *state) structure(src, base reflect.Value, t reflect.Type, path string, depth int) (reflect.Value, error) {
+	if err := s.reserve(1, t.Size(), path); err != nil {
+		return reflect.Value{}, err
+	}
+	out := reflect.New(t).Elem()
+	out.Set(base)
+	if src.Type() == t {
+		// Private scalar state may be assigned as part of its whole value; mutable
+		// private state requires a converter, never unsafe writes or silent loss.
+		for i := 0; i < t.NumField(); i++ {
+			f := t.Field(i)
+			if f.PkgPath != "" && s.options.deep && privateMutable(f.Type) {
+				return reflect.Value{}, at(path+"."+f.Name, ErrUnsupported)
+			}
+		}
+		out.Set(src)
+	} else {
+		for i := 0; i < t.NumField(); i++ {
+			if t.Field(i).PkgPath != "" {
+				return reflect.Value{}, at(path, ErrUnsupported)
+			}
+		}
+	}
+	from, to := exportedFields(src.Type()), exportedFields(t)
+	rules := s.options.fields[pair{src.Type(), t}]
+	if rules == nil {
+		rules = &fields{map[string]string{}, map[string]bool{}, map[string]bool{}}
+	}
+	reverse := map[string]string{}
+	for a, b := range rules.names {
+		reverse[b] = a
+	}
+	names := make([]string, 0, len(to))
+	for n := range to {
+		names = append(names, n)
+	}
+	sort.Strings(names)
+	used := map[string]bool{}
+	for _, name := range names {
+		target := to[name]
+		old, _ := fieldValue(base, target.Index)
+		if rules.ignoreTarget[name] {
+			if !old.IsValid() {
+				old = reflect.Zero(target.Type)
+			}
+			if err := setField(out, target.Index, old); err != nil {
+				return reflect.Value{}, at(path+"."+name, err)
+			}
+			continue
+		}
+		srcName := name
+		if renamed, ok := reverse[name]; ok {
+			srcName = renamed
+		}
+		source, ok := from[srcName]
+		if !ok || rules.ignoreSource[srcName] {
+			return reflect.Value{}, at(path+"."+name, ErrField)
+		}
+		used[srcName] = true
+		v, ok := fieldValue(src, source.Index)
+		if !ok {
+			return reflect.Value{}, at(path+"."+name, ErrNil)
+		}
+		value, err := s.walk(v, old, target.Type, path+"."+name, depth+1)
+		if err != nil {
+			return reflect.Value{}, err
+		}
+		if err = setField(out, target.Index, value); err != nil {
+			return reflect.Value{}, at(path+"."+name, err)
+		}
+	}
+	if s.options.strict {
+		for name := range from {
+			if !used[name] && !rules.ignoreSource[name] {
+				return reflect.Value{}, at(path+"."+name, ErrField)
+			}
+		}
+	}
+	return out, nil
+}
--- a/copyx/copy_test.go
+++ b/copyx/copy_test.go
@@ -0,0 +1,448 @@
+package copyx_test
+
+import (
+	"errors"
+	"fmt"
+	"reflect"
+	"strings"
+	"sync"
+	"testing"
+	"time"
+
+	"git.yuntuo.hk/k2safe/go-omni/copyx"
+)
+
+type detail struct {
+	Values []int
+	Index  map[string][]int
+	Next   *detail
+}
+
+func TestDeepGraph(t *testing.T) {
+	src := &detail{Values: []int{1, 2}, Index: map[string][]int{"a": {3}}}
+	src.Next = src
+	dst, err := copyx.Clone(src)
+	if err != nil {
+		t.Fatal(err)
+	}
+	if dst == src || dst.Next != dst {
+		t.Fatal("pointer cycle not preserved")
+	}
+	dst.Values[0] = 9
+	dst.Index["a"][0] = 8
+	if src.Values[0] != 1 || src.Index["a"][0] != 3 {
+		t.Fatal("deep alias")
+	}
+	m := map[string]any{}
+	m["self"] = m
+	n, err := copyx.Clone(m)
+	if err != nil {
+		t.Fatal(err)
+	}
+	n["self"].(map[string]any)["new"] = 1
+	if n["new"] != 1 || m["new"] != nil {
+		t.Fatal("map cycle changed")
+	}
+	x := []any{nil}
+	x[0] = x
+	y, err := copyx.Clone(x)
+	if err != nil {
+		t.Fatal(err)
+	}
+	y[0].([]any)[0] = "changed"
+	if y[0] != "changed" {
+		t.Fatal("slice cycle changed")
+	}
+	if _, ok := x[0].([]any); !ok {
+		t.Fatal("source slice changed")
+	}
+}
+func TestShallowAndNil(t *testing.T) {
+	src := detail{Values: []int{1}}
+	var dst detail
+	if err := copyx.Copy(&dst, src); err != nil {
+		t.Fatal(err)
+	}
+	dst.Values[0] = 2
+	if src.Values[0] != 2 {
+		t.Fatal("shallow unexpectedly detached")
+	}
+	for _, slice := range [][]int{nil, {}} {
+		out, err := copyx.Clone(slice)
+		if err != nil || (out == nil) != (slice == nil) {
+			t.Fatal(out, err)
+		}
+	}
+	for _, m := range []map[string]int{nil, {}} {
+		out, err := copyx.Clone(m)
+		if err != nil || (out == nil) != (m == nil) {
+			t.Fatal(out, err)
+		}
+	}
+	var p *int
+	n := 7
+	if err := copyx.Copy(&n, p); !errors.Is(err, copyx.ErrNil) || n != 7 {
+		t.Fatal(n, err)
+	}
+	if err := copyx.Copy(&n, p, copyx.WithNilPolicy(copyx.NilSkip)); err != nil || n != 7 {
+		t.Fatal(n, err)
+	}
+	if err := copyx.Copy(&n, p, copyx.WithNilPolicy(copyx.NilZero)); err != nil || n != 0 {
+		t.Fatal(n, err)
+	}
+	x := 3
+	out := &x
+	if err := copyx.Copy(&out, p); err != nil || out != nil {
+		t.Fatal(out, err)
+	}
+	flag := true
+	if err := copyx.Copy(&flag, false); err != nil || flag {
+		t.Fatal(flag, err)
+	}
+	flag = true
+	if err := copyx.Copy(&flag, false, copyx.WithSkipZero()); err != nil || !flag {
+		t.Fatal(flag, err)
+	}
+}
+
+func TestConverterAliasesRejected(t *testing.T) {
+	for _, kind := range []string{"same", "nested", "subslice", "capacity", "fieldPointer", "private", "map", "sibling"} {
+		t.Run(kind, func(t *testing.T) {
+			src := &detail{Values: []int{1, 2, 3}, Index: map[string][]int{"x": {1}}}
+			var err error
+			switch kind {
+			case "same":
+				_, err = copyx.Clone(src, copyx.WithConverter(func(v *detail) (*detail, error) { return v, nil }))
+			case "nested":
+				_, err = copyx.Clone(src, copyx.WithConverter(func(v *detail) (*detail, error) { return &detail{Values: v.Values}, nil }))
+			case "subslice":
+				_, err = copyx.Clone(src.Values, copyx.WithConverter(func(v []int) ([]int, error) { return v[1:], nil }))
+			case "capacity":
+				_, err = copyx.Clone(src.Values, copyx.WithConverter(func(v []int) ([]int, error) { return v[:0], nil }))
+			case "map":
+				_, err = copyx.Clone(src.Index, copyx.WithConverter(func(v map[string][]int) (map[string][]int, error) { return v, nil }))
+			case "fieldPointer":
+				var dst *int
+				err = copyx.Copy(&dst, src.Values, copyx.WithDeepCopy(), copyx.WithConverter(func(v []int) (*int, error) { return &v[1], nil }))
+			case "private":
+				type opaque struct{ data []int }
+				v := opaque{src.Values}
+				_, err = copyx.Clone(v, copyx.WithConverter(func(v opaque) (opaque, error) { return v, nil }))
+			case "sibling":
+				type object struct{ A, B []int }
+				v := object{[]int{1}, []int{2}}
+				_, err = copyx.Clone(v, copyx.WithConverter(func(_ []int) ([]int, error) { return v.B, nil }))
+			}
+			if !errors.Is(err, copyx.ErrSharedReference) {
+				t.Fatalf("got %v", err)
+			}
+		})
+	}
+	_, err := copyx.Clone(4, copyx.WithConverter(func(v int) (int, error) { return v, nil }))
+	if err != nil {
+		t.Fatal("equal primitive rejected", err)
+	}
+	_, err = copyx.Clone("same", copyx.WithConverter(func(v string) (string, error) { return v, nil }))
+	if err != nil {
+		t.Fatal(err)
+	}
+	good, err := copyx.Clone([]int{1}, copyx.WithConverter(func(v []int) ([]int, error) { return append([]int(nil), v...), nil }))
+	if err != nil || good[0] != 1 {
+		t.Fatal(good, err)
+	}
+}
+
+func TestPrivateAndUnsupported(t *testing.T) {
+	type money struct{ cents *int64 }
+	n := int64(9007199254740991)
+	src := money{&n}
+	if _, err := copyx.Clone(src); !errors.Is(err, copyx.ErrUnsupported) {
+		t.Fatal(err)
+	}
+	out, err := copyx.Clone(src, copyx.WithConverter(func(v money) (money, error) { n := *v.cents; return money{&n}, nil }))
+	if err != nil || *out.cents != n || out.cents == src.cents {
+		t.Fatal(out, err)
+	}
+	tm := time.Now()
+	cloned, err := copyx.Clone(tm)
+	if err != nil || !cloned.Equal(tm) {
+		t.Fatal(cloned, err)
+	}
+	for _, v := range []any{make(chan int), func() {}, &sync.Mutex{}, sync.Mutex{}} {
+		if _, err := copyx.Clone(v); !errors.Is(err, copyx.ErrUnsupported) {
+			t.Fatalf("%T: %v", v, err)
+		}
+	}
+}
+
+func TestNilTypeMismatchAndInterfaceConverter(t *testing.T) {
+	var source *string
+	target := 7
+	if err := copyx.Copy(&target, source, copyx.WithNilPolicy(copyx.NilZero)); !errors.Is(err, copyx.ErrType) || target != 7 {
+		t.Fatal(target, err)
+	}
+	var list []int
+	var targetMap map[string]int
+	if err := copyx.Copy(&targetMap, list); !errors.Is(err, copyx.ErrType) {
+		t.Fatal(err)
+	}
+	type input struct{ Value any }
+	type output struct{ Value string }
+	var out output
+	err := copyx.Copy(&out, input{}, copyx.WithConverter(func(v any) (string, error) {
+		if v == nil {
+			return "nil handled", nil
+		}
+		return "value", nil
+	}))
+	if err != nil || out.Value != "nil handled" {
+		t.Fatal(out, err)
+	}
+	var lock sync.Mutex
+	if err := copyx.Copy(&lock, sync.Mutex{}); !errors.Is(err, copyx.ErrUnsupported) {
+		t.Fatal(err)
+	}
+	type locked struct {
+		mu    sync.Mutex
+		Value int
+	}
+	var l locked
+	if err := copyx.Copy(&l, locked{}); !errors.Is(err, copyx.ErrUnsupported) {
+		t.Fatal(err)
+	}
+}
+
+func TestAllocationLimitAndPointerRoot(t *testing.T) {
+	src := make([]byte, (64<<20)+1)
+	if _, err := copyx.Clone(src); !errors.Is(err, copyx.ErrLimit) {
+		t.Fatal(err)
+	}
+	n := &detail{}
+	n.Next = n
+	var value detail
+	if err := copyx.Copy(&value, n, copyx.WithDeepCopy()); !errors.Is(err, copyx.ErrUnsupported) {
+		t.Fatal(err)
+	}
+	var p *detail
+	if err := copyx.Copy(&p, n, copyx.WithDeepCopy()); err != nil || p.Next != p || p == n {
+		t.Fatal(p, err)
+	}
+}
+func TestFieldsConvertersAndAtomicity(t *testing.T) {
+	type input struct {
+		Name  string
+		Age   int
+		Extra string
+	}
+	type output struct {
+		Label string
+		Age   int
+		Local string
+	}
+	rename := map[string]string{"Name": "Label"}
+	c, err := copyx.New(copyx.WithFieldNames[input, output](rename), copyx.WithIgnoreTarget[input, output]("Local"))
+	if err != nil {
+		t.Fatal(err)
+	}
+	rename["Name"] = "Missing"
+	dst := output{Local: "preserved"}
+	if err = c.Copy(&dst, input{Name: "hello", Age: 2}); err != nil || dst.Label != "hello" || dst.Local != "preserved" {
+		t.Fatal(dst, err)
+	}
+	if err = copyx.Copy(&dst, input{}, copyx.WithStrictFields(), copyx.WithFieldNames[input, output](map[string]string{"Name": "Label"}), copyx.WithIgnoreTarget[input, output]("Local")); !errors.Is(err, copyx.ErrField) {
+		t.Fatal(err)
+	}
+	if err = copyx.Copy(&dst, input{}, copyx.WithStrictFields(), copyx.WithFieldNames[input, output](map[string]string{"Name": "Label"}), copyx.WithIgnoreTarget[input, output]("Local"), copyx.WithIgnoreSource[input, output]("Extra")); err != nil {
+		t.Fatal(err)
+	}
+	if err = copyx.Copy(&dst, input{}); !errors.Is(err, copyx.ErrField) {
+		t.Fatal(err)
+	}
+	if _, err = copyx.New(copyx.WithFieldNames[input, output](map[string]string{"Nope": "Age"})); err == nil {
+		t.Fatal("invalid rule accepted")
+	}
+	if _, err = copyx.New(copyx.WithConverter(func(v int) (string, error) { return "", nil }), copyx.WithConverter(func(v int) (string, error) { return "", nil })); err == nil {
+		t.Fatal("duplicate converter accepted")
+	}
+
+	sentinel := errors.New("conversion failed")
+	type node struct {
+		A []int
+		Z string
+	}
+	old := node{[]int{8}, "old"}
+	before := old.A
+	err = copyx.Copy(&old, node{[]int{1}, "bad"}, copyx.WithDeepCopy(), copyx.WithConverter(func(v string) (string, error) { return "", sentinel }))
+	if !errors.Is(err, sentinel) || !strings.Contains(err.Error(), "Z") || old.Z != "old" || old.A[0] != 8 || &old.A[0] != &before[0] {
+		t.Fatal(old, err)
+	}
+	// Exact typed nil converter must get control before the global nil policy.
+	var ptr *int
+	var value int
+	err = copyx.Copy(&value, ptr, copyx.WithConverter(func(v *int) (int, error) {
+		if v == nil {
+			return 0, sentinel
+		}
+		return *v, nil
+	}))
+	if !errors.Is(err, sentinel) {
+		t.Fatal(err)
+	}
+	var small int8 = 3
+	if err = copyx.Copy(&small, int64(300)); !errors.Is(err, copyx.ErrType) || small != 3 {
+		t.Fatal(small, err)
+	}
+}
+
+type Embedded struct {
+	A int
+	Z string
+}
+
+func TestEmbeddedDestinationDetached(t *testing.T) {
+	type target struct{ *Embedded }
+	type source struct {
+		A int
+		Z int
+	}
+	ptr := &Embedded{5, "keep"}
+	dst := target{ptr}
+	if err := copyx.Copy(&dst, source{6, 7}); !errors.Is(err, copyx.ErrType) {
+		t.Fatal(err)
+	}
+	if ptr.A != 5 || dst.Embedded != ptr {
+		t.Fatal("failure mutated embedded target")
+	}
+	if err := copyx.Copy(&dst, Embedded{6, "new"}); err != nil {
+		t.Fatal(err)
+	}
+	if ptr.A != 5 || dst.A != 6 {
+		t.Fatal("success mutated old embedded object")
+	}
+}
+func TestConcurrentCopier(t *testing.T) {
+	c, err := copyx.New(copyx.WithDeepCopy())
+	if err != nil {
+		t.Fatal(err)
+	}
+	src := &detail{Values: []int{7}, Index: map[string][]int{"a": {9}}}
+	var wg sync.WaitGroup
+	for i := 0; i < 64; i++ {
+		wg.Add(1)
+		go func() {
+			defer wg.Done()
+			for n := 0; n < 20; n++ {
+				var dst *detail
+				if err := c.Copy(&dst, src); err != nil {
+					t.Error(err)
+					return
+				}
+				dst.Values[0] = n
+				if src.Values[0] != 7 {
+					t.Error("shared")
+				}
+			}
+		}()
+	}
+	wg.Wait()
+}
+func TestBoundAndCollections(t *testing.T) {
+	src := &detail{}
+	p := src
+	for i := 0; i < 300; i++ {
+		p.Next = &detail{}
+		p = p.Next
+	}
+	if _, err := copyx.Clone(src); !errors.Is(err, copyx.ErrLimit) {
+		t.Fatal(err)
+	}
+	type from struct{ Value string }
+	type to struct{ Value string }
+	var out []to
+	if err := copyx.Copy(&out, []from{{"a"}, {"b"}}); err != nil || len(out) != 2 || out[1].Value != "b" {
+		t.Fatal(out, err)
+	}
+	var array [2]to
+	if err := copyx.Copy(&array, [2]from{{"a"}, {"b"}}); err != nil {
+		t.Fatal(err)
+	}
+	if err := copyx.Copy(&array, [1]from{{"a"}}); !errors.Is(err, copyx.ErrType) {
+		t.Fatal(err)
+	}
+	var outMap map[string]int
+	err := copyx.Copy(&outMap, map[int]int{1: 1, 2: 2}, copyx.WithConverter(func(int) (string, error) { return "same", nil }))
+	if err == nil || outMap != nil {
+		t.Fatal(outMap, err)
+	}
+}
+func FuzzClone(f *testing.F) {
+	f.Add([]byte{1, 2, 3})
+	f.Add([]byte{})
+	f.Fuzz(func(t *testing.T, data []byte) {
+		if len(data) > 1024 {
+			data = data[:1024]
+		}
+		src := map[string]any{"bytes": data, "other": []string{"x"}}
+		out, err := copyx.Clone(src)
+		if err != nil {
+			t.Fatal(err)
+		}
+		if !reflect.DeepEqual(src, out) {
+			t.Fatal("changed value")
+		}
+		if len(data) > 0 {
+			out["bytes"].([]byte)[0] ^= 255
+			if data[0] == out["bytes"].([]byte)[0] {
+				t.Fatal("alias")
+			}
+		}
+	})
+}
+
+func TestTraversalNodeLimit(t *testing.T) {
+	source := make([]any, 200001)
+	if _, err := copyx.Clone(source); !errors.Is(err, copyx.ErrLimit) {
+		t.Fatal("expected bounded traversal", err)
+	}
+}
+
+func TestNilCannotHideFieldMismatch(t *testing.T) {
+	type source struct{ Value string }
+	type target struct{ Value int }
+	var src *source
+	var dst *target
+	for _, policy := range []copyx.NilPolicy{copyx.NilError, copyx.NilZero, copyx.NilSkip} {
+		if err := copyx.Copy(&dst, src, copyx.WithNilPolicy(policy)); !errors.Is(err, copyx.ErrType) {
+			t.Fatal("nil concealed incompatible fields", err)
+		}
+	}
+	if err := copyx.Copy(&dst, src, copyx.WithConverter(func(string) (int, error) { return 0, nil })); err != nil {
+		t.Fatal(err)
+	}
+	text := "keep"
+	if err := copyx.Copy(&text, 0, copyx.WithSkipZero()); !errors.Is(err, copyx.ErrType) || text != "keep" {
+		t.Fatal("zero concealed incompatible types", text, err)
+	}
+}
+func BenchmarkCopy(b *testing.B) {
+	for _, n := range []int{1, 100, 1000} {
+		for _, deep := range []bool{false, true} {
+			b.Run(fmt.Sprintf("fields%d/deep%t", n, deep), func(b *testing.B) {
+				src := detail{Values: make([]int, n), Index: map[string][]int{"one": {1, 2}}}
+				var opts []copyx.Option
+				if deep {
+					opts = append(opts, copyx.WithDeepCopy())
+				}
+				c, _ := copyx.New(opts...)
+				b.ReportAllocs()
+				b.ResetTimer()
+				for i := 0; i < b.N; i++ {
+					var dst detail
+					if err := c.Copy(&dst, src); err != nil {
+						b.Fatal(err)
+					}
+				}
+			})
+		}
+	}
+}
--- a/copyx/graph.go
+++ b/copyx/graph.go
@@ -0,0 +1,270 @@
+package copyx
+
+import (
+	"fmt"
+	"reflect"
+	"sort"
+	"sync"
+	"time"
+)
+
+const maxDepth = 256
+const maxNodes = 200000
+const maxCopyBytes = 64 << 20
+
+var timeType = reflect.TypeFor[time.Time]()
+
+// Immutable type metadata is shared, never values or converter registrations.
+var valueTypes sync.Map
+
+func simpleValue(t reflect.Type) bool {
+	if known, ok := valueTypes.Load(t); ok {
+		return known.(bool)
+	}
+	result := t == timeType
+	if !result {
+		switch t.Kind() {
+		case reflect.Bool, reflect.Int, reflect.Int8, reflect.Int16, reflect.Int32, reflect.Int64,
+			reflect.Uint, reflect.Uint8, reflect.Uint16, reflect.Uint32, reflect.Uint64, reflect.Uintptr,
+			reflect.Float32, reflect.Float64, reflect.Complex64, reflect.Complex128, reflect.String:
+			result = true
+		case reflect.Array:
+			result = simpleValue(t.Elem())
+		case reflect.Struct:
+			result = !forbidden(t)
+			for i := 0; result && i < t.NumField(); i++ {
+				result = simpleValue(t.Field(i).Type)
+			}
+		}
+	}
+	valueTypes.Store(t, result)
+	return result
+}
+
+type reference struct {
+	kind             reflect.Kind
+	typ              reflect.Type
+	ptr              uintptr
+	length, capacity int
+}
+
+func identity(v reflect.Value) reference {
+	r := reference{kind: v.Kind(), typ: v.Type(), ptr: uintptr(v.UnsafePointer())}
+	if v.Kind() == reflect.Slice {
+		r.length = v.Len()
+		r.capacity = v.Cap()
+	}
+	return r
+}
+
+type span struct{ start, end uintptr }
+type graph struct {
+	maps   map[uintptr]bool
+	spans  []span
+	maxEnd []uintptr
+}
+
+// References are inspected without reading private values through Interface or
+// using unsafe writes. Slice capacity matters: returning source[:0] is an alias.
+func scanGraph(v reflect.Value, visit func(reflect.Value, string) error) error {
+	seen := map[reference]bool{}
+	nodes := 0
+	var walk func(reflect.Value, string, int) error
+	walk = func(v reflect.Value, path string, depth int) error {
+		nodes++
+		if depth > maxDepth || nodes > maxNodes {
+			return at(path, ErrLimit)
+		}
+		if !v.IsValid() {
+			return nil
+		}
+		if err := visit(v, path); err != nil {
+			return err
+		}
+		if simpleValue(v.Type()) {
+			return nil
+		} // time.Time is a documented immutable value.
+		switch v.Kind() {
+		case reflect.Interface:
+			if !v.IsNil() {
+				return walk(v.Elem(), path, depth+1)
+			}
+		case reflect.Pointer, reflect.Map, reflect.Slice:
+			if v.IsNil() {
+				return nil
+			}
+			id := identity(v)
+			if seen[id] {
+				return nil
+			}
+			seen[id] = true
+			switch v.Kind() {
+			case reflect.Pointer:
+				return walk(v.Elem(), path, depth+1)
+			case reflect.Map:
+				it := v.MapRange()
+				for it.Next() {
+					if err := walk(it.Key(), path+"[key]", depth+1); err != nil {
+						return err
+					}
+					if err := walk(it.Value(), path+"[value]", depth+1); err != nil {
+						return err
+					}
+				}
+			case reflect.Slice:
+				if simpleValue(v.Type().Elem()) {
+					return nil
+				}
+				all := v.Slice(0, v.Cap())
+				for i := 0; i < all.Len(); i++ {
+					if err := walk(all.Index(i), fmt.Sprintf("%s[%d]", path, i), depth+1); err != nil {
+						return err
+					}
+				}
+			}
+		case reflect.Struct:
+			for i := 0; i < v.NumField(); i++ {
+				if err := walk(v.Field(i), path+"."+v.Type().Field(i).Name, depth+1); err != nil {
+					return err
+				}
+			}
+		case reflect.Array:
+			for i := 0; i < v.Len(); i++ {
+				if err := walk(v.Index(i), fmt.Sprintf("%s[%d]", path, i), depth+1); err != nil {
+					return err
+				}
+			}
+		}
+		return nil
+	}
+	return walk(v, "$", 0)
+}
+func mutableSpan(v reflect.Value) (span, bool) {
+	var n uintptr
+	switch v.Kind() {
+	case reflect.Pointer:
+		if v.IsNil() {
+			return span{}, false
+		}
+		n = v.Type().Elem().Size()
+	case reflect.Slice:
+		if v.IsNil() {
+			return span{}, false
+		}
+		n = uintptr(v.Cap()) * v.Type().Elem().Size()
+	default:
+		return span{}, false
+	}
+	if n == 0 {
+		return span{}, false
+	}
+	start := uintptr(v.UnsafePointer())
+	return span{start, start + n}, true
+}
+func sourceGraph(v reflect.Value) (*graph, error) {
+	g := &graph{maps: map[uintptr]bool{}}
+	err := scanGraph(v, func(v reflect.Value, _ string) error {
+		if r, ok := mutableSpan(v); ok {
+			g.spans = append(g.spans, r)
+		}
+		if v.Kind() == reflect.Map && !v.IsNil() {
+			g.maps[uintptr(v.UnsafePointer())] = true
+		}
+		return nil
+	})
+	sort.Slice(g.spans, func(i, j int) bool { return g.spans[i].start < g.spans[j].start })
+	var end uintptr
+	for _, r := range g.spans {
+		if r.end > end {
+			end = r.end
+		}
+		g.maxEnd = append(g.maxEnd, end)
+	}
+	return g, err
+}
+func (g *graph) audit(v reflect.Value) error {
+	return scanGraph(v, func(v reflect.Value, path string) error {
+		if forbidden(v.Type()) {
+			return at(path, ErrUnsupported)
+		}
+		switch v.Kind() {
+		case reflect.Func, reflect.Chan:
+			if !v.IsNil() {
+				return at(path, ErrUnsupported)
+			}
+		case reflect.UnsafePointer:
+			if v.Pointer() != 0 {
+				return at(path, ErrUnsupported)
+			}
+		}
+		if v.Kind() == reflect.Map && !v.IsNil() && g.maps[uintptr(v.UnsafePointer())] {
+			return at(path, ErrSharedReference)
+		}
+		if r, ok := mutableSpan(v); ok {
+			i := sort.Search(len(g.spans), func(i int) bool { return g.spans[i].start >= r.end })
+			if i > 0 && g.maxEnd[i-1] > r.start {
+				return at(path, ErrSharedReference)
+			}
+		}
+		return nil
+	})
+}
+func forbidden(t reflect.Type) bool {
+	// Lock/resource implementations are not data. A custom converter may turn
+	// them into a different data type but may not manufacture cloned handles.
+	switch t.PkgPath() {
+	case "sync", "sync/atomic", "os", "net", "database/sql":
+		return t.Kind() == reflect.Struct
+	}
+	return false
+}
+
+// Shallow copies may share handles through pointers, but must not copy lock or
+// resource state by value, including state inside a containing struct/array.
+var safeValueTypes sync.Map
+
+func shallowSafe(t reflect.Type) bool {
+	if known, ok := safeValueTypes.Load(t); ok {
+		return known.(bool)
+	}
+	result := true
+	if forbidden(t) {
+		safeValueTypes.Store(t, false)
+		return false
+	}
+	switch t.Kind() {
+	case reflect.Struct:
+		for i := 0; i < t.NumField(); i++ {
+			if !shallowSafe(t.Field(i).Type) {
+				result = false
+				break
+			}
+		}
+	case reflect.Array:
+		result = shallowSafe(t.Elem())
+	}
+	safeValueTypes.Store(t, result)
+	return result
+}
+
+func privateMutable(t reflect.Type) bool {
+	if t == timeType {
+		return false
+	}
+	switch t.Kind() {
+	case reflect.Pointer, reflect.Map, reflect.Slice, reflect.Interface, reflect.Func, reflect.Chan, reflect.UnsafePointer:
+		return true
+	case reflect.Array:
+		return privateMutable(t.Elem())
+	case reflect.Struct:
+		if forbidden(t) {
+			return true
+		}
+		for i := 0; i < t.NumField(); i++ {
+			if privateMutable(t.Field(i).Type) {
+				return true
+			}
+		}
+	}
+	return false
+}
--- a/copyx/options.go
+++ b/copyx/options.go
@@ -0,0 +1,169 @@
+// Package copyx copies Go values without JSON, generated code or global registration.
+package copyx
+
+import (
+	"errors"
+	"fmt"
+	"reflect"
+)
+
+// NilPolicy controls nil input. NilError preserves nil for nullable targets and
+// rejects nil to non-nullable targets. NilSkip retains the existing target.
+type NilPolicy uint8
+
+const (
+	NilError NilPolicy = iota
+	NilZero
+	NilSkip
+)
+
+type pair struct{ from, to reflect.Type }
+type converter func(reflect.Value) (reflect.Value, error)
+type fields struct {
+	names                      map[string]string
+	ignoreSource, ignoreTarget map[string]bool
+}
+type settings struct {
+	deep, skipZero, strict bool
+	nilPolicy              NilPolicy
+	converters             map[pair]converter
+	fields                 map[pair]*fields
+}
+
+// Option configures one immutable Copier. Options never change global behavior.
+type Option func(*settings) error
+
+func WithDeepCopy() Option { return func(s *settings) error { s.deep = true; return nil } }
+
+// WithSkipZero explicitly skips Go zero values, including false, 0 and "".
+func WithSkipZero() Option { return func(s *settings) error { s.skipZero = true; return nil } }
+
+// WithStrictFields additionally rejects unconsumed exported source fields.
+// Target fields must have a source by default, unless explicitly ignored.
+func WithStrictFields() Option { return func(s *settings) error { s.strict = true; return nil } }
+func WithNilPolicy(p NilPolicy) Option {
+	return func(s *settings) error {
+		if p > NilSkip {
+			return errors.New("copyx: invalid nil policy")
+		}
+		s.nilPolicy = p
+		return nil
+	}
+}
+
+// WithConverter registers an exact source/target type pair. Typed nils are
+// delivered to converters before default nil handling. The function must not
+// mutate its input and must be safe for concurrent calls when Copier is shared.
+func WithConverter[S, T any](fn func(S) (T, error)) Option {
+	return func(s *settings) error {
+		if fn == nil {
+			return errors.New("copyx: nil converter")
+		}
+		key := pair{reflect.TypeFor[S](), reflect.TypeFor[T]()}
+		if _, exists := s.converters[key]; exists {
+			return fmt.Errorf("copyx: duplicate converter %s -> %s", key.from, key.to)
+		}
+		s.converters[key] = func(v reflect.Value) (reflect.Value, error) {
+			var input S
+			reflect.ValueOf(&input).Elem().Set(v)
+			out, err := fn(input)
+			return reflect.ValueOf(&out).Elem(), err
+		}
+		return nil
+	}
+}
+
+// WithFieldNames declares source -> target Go field names for one struct pair.
+// It is not a JSON tag mapping. Only actual, unambiguous exported fields qualify.
+func WithFieldNames[S, T any](names map[string]string) Option {
+	copyNames := make(map[string]string, len(names))
+	for k, v := range names {
+		copyNames[k] = v
+	}
+	return fieldOption[S, T](func(f *fields) error {
+		for from, to := range copyNames {
+			if _, exists := f.names[from]; exists {
+				return fmt.Errorf("copyx: duplicate field rule %s", from)
+			}
+			f.names[from] = to
+		}
+		return nil
+	})
+}
+func WithIgnoreSource[S, T any](names ...string) Option {
+	names = append([]string(nil), names...)
+	return fieldOption[S, T](func(f *fields) error {
+		for _, n := range names {
+			f.ignoreSource[n] = true
+		}
+		return nil
+	})
+}
+
+// WithIgnoreTarget preserves the corresponding existing target fields in Copy.
+// Deep mode rejects that preservation if it would retain a source reference.
+func WithIgnoreTarget[S, T any](names ...string) Option {
+	names = append([]string(nil), names...)
+	return fieldOption[S, T](func(f *fields) error {
+		for _, n := range names {
+			f.ignoreTarget[n] = true
+		}
+		return nil
+	})
+}
+func fieldOption[S, T any](apply func(*fields) error) Option {
+	return func(s *settings) error {
+		key := pair{reflect.TypeFor[S](), reflect.TypeFor[T]()}
+		if key.from.Kind() != reflect.Struct || key.to.Kind() != reflect.Struct {
+			return errors.New("copyx: field options require struct types")
+		}
+		f := s.fields[key]
+		if f == nil {
+			f = &fields{map[string]string{}, map[string]bool{}, map[string]bool{}}
+			s.fields[key] = f
+		}
+		return apply(f)
+	}
+}
+
+// Copier is immutable after construction. Each Copy owns its traversal state.
+type Copier struct{ options settings }
+
+func New(options ...Option) (*Copier, error) {
+	s := settings{converters: map[pair]converter{}, fields: map[pair]*fields{}}
+	for _, option := range options {
+		if option == nil {
+			return nil, errors.New("copyx: nil option")
+		}
+		if err := option(&s); err != nil {
+			return nil, err
+		}
+	}
+	for key, f := range s.fields {
+		from, to := exportedFields(key.from), exportedFields(key.to)
+		used := map[string]bool{}
+		for src, dst := range f.names {
+			if _, ok := from[src]; !ok {
+				return nil, fmt.Errorf("copyx: unknown source field %s.%s", key.from, src)
+			}
+			if _, ok := to[dst]; !ok {
+				return nil, fmt.Errorf("copyx: unknown target field %s.%s", key.to, dst)
+			}
+			if used[dst] || f.ignoreSource[src] || f.ignoreTarget[dst] {
+				return nil, fmt.Errorf("copyx: conflicting field rule %s", dst)
+			}
+			used[dst] = true
+		}
+		for n := range f.ignoreSource {
+			if _, ok := from[n]; !ok {
+				return nil, fmt.Errorf("copyx: unknown source field %s", n)
+			}
+		}
+		for n := range f.ignoreTarget {
+			if _, ok := to[n]; !ok {
+				return nil, fmt.Errorf("copyx: unknown target field %s", n)
+			}
+		}
+	}
+	return &Copier{options: s}, nil
+}
--- a/examples/configuration/README.md
+++ b/examples/configuration/README.md
@@ -0,0 +1,21 @@
+# 统一配置加载示例
+
+从框架根目录运行，无需数据库或外部服务：
+
+```sh
+go run ./examples/configuration
+go run ./examples/configuration -format json
+go run ./examples/configuration -format xml
+DEMO_CLIENT_TIMEOUT=500ms DEMO_MAX_ITEMS=0 go run ./examples/configuration
+DEMO_MAX_ITEMS=wrong go run ./examples/configuration
+```
+
+前三次都输出 `timeout=2s maxItems=100 allowed=[json xml]`。环境覆盖允许显式零值。
+最后一条输出定位 `maxItems` / `DEMO_MAX_ITEMS` 的安全错误，不打印输入原值。
+也可 `-config /path/to/app.yaml` 读取自己的文件。示例没有建立网络连接。
+
+`Config` 定义字段，`envDefault` 定义缺省值，`Validate` 用 `config.Invalid` 返回字段与公开原因。
+`newLoader` 额外注册 `.custom`（演示复用 JSON decoder）；同一个 `load` 可读取所有格式。
+JSON/YAML/XML 直接可用，无需注册。新增格式只修改解析器注册，不改业务结构或校验。
+
+只打印选定非敏感字段，不输出整个配置。完整格式、错误定位和旧项目迁移见 [CONFIG.md](../../CONFIG.md)。
--- a/examples/configuration/config.json
+++ b/examples/configuration/config.json
@@ -0,0 +1,5 @@
+{
+  "client": {"endpoint": "https://example.com", "timeout": "2s"},
+  "maxItems": 100,
+  "allowed": ["json", "xml"]
+}
--- a/examples/configuration/config.xml
+++ b/examples/configuration/config.xml
@@ -0,0 +1,8 @@
+<config>
+  <client>
+    <endpoint>https://example.com</endpoint>
+    <timeout>2s</timeout>
+  </client>
+  <maxItems>100</maxItems>
+  <allowed type="array"><item>json</item><item>xml</item></allowed>
+</config>
--- a/examples/configuration/config.yaml
+++ b/examples/configuration/config.yaml
@@ -0,0 +1,5 @@
+client:
+  endpoint: https://example.com
+  timeout: 2s
+maxItems: 100
+allowed: [json, xml]
--- a/examples/configuration/main.go
+++ b/examples/configuration/main.go
@@ -0,0 +1,85 @@
+// Run with go run ./examples/configuration -format xml, or -config /path/to/app.yaml.
+package main
+
+import (
+	"embed"
+	"flag"
+	"fmt"
+	"os"
+	"path/filepath"
+	"time"
+
+	"git.yuntuo.hk/k2safe/go-omni/config"
+)
+
+//go:embed config.json config.yaml config.xml
+var examples embed.FS
+
+type ClientConfig struct {
+	Endpoint string        `json:"endpoint"`
+	Timeout  time.Duration `json:"timeout" envDefault:"3s"`
+	// This field is deliberately unavailable to configuration files.
+	Token string `json:"-" env:"DEMO_CLIENT_TOKEN,secret"`
+}
+type Config struct {
+	Client   ClientConfig `json:"client"`
+	MaxItems int          `json:"maxItems" envDefault:"20"`
+	Allowed  []string     `json:"allowed"`
+}
+
+func (c Config) Validate() error {
+	if c.Client.Timeout <= 0 {
+		return config.Invalid("client.timeout", "must be positive")
+	}
+	if c.MaxItems < 0 {
+		return config.Invalid("maxItems", "must not be negative")
+	}
+	return nil
+}
+func newLoader() (*config.Loader, error) {
+	// Example of an instance-local extension. A TOML/etc. adapter can implement
+	// Decoder and return Document using that parser instead; no global registry.
+	return config.NewLoader(config.WithDecoder("custom", config.DecoderFunc(func(data []byte) (config.Document, error) {
+		return (config.JSONDecoder{}).Decode(data)
+	})))
+}
+func load(path string) (Config, error) {
+	loader, err := newLoader()
+	if err != nil {
+		return Config{}, err
+	}
+	return config.LoadProject(path, Config{}, config.EnvOptions{Prefix: "DEMO_", Empty: "reject"}, loader)
+}
+func run() error {
+	path := flag.String("config", "", "external configuration file")
+	format := flag.String("format", "yaml", "embedded example: json, yaml, xml")
+	flag.Parse()
+	if *path == "" {
+		data, err := examples.ReadFile("config." + *format)
+		if err != nil {
+			return fmt.Errorf("choose json, yaml or xml")
+		}
+		dir, err := os.MkdirTemp("", "goOmniConfiguration-")
+		if err != nil {
+			return err
+		}
+		defer os.RemoveAll(dir)
+		*path = filepath.Join(dir, "config."+*format)
+		if err = os.WriteFile(*path, data, 0600); err != nil {
+			return err
+		}
+	}
+	cfg, err := load(*path)
+	if err != nil {
+		return err
+	}
+	// Print selected non-sensitive fields, never the whole configuration.
+	fmt.Printf("timeout=%s maxItems=%d allowed=%v\n", cfg.Client.Timeout, cfg.MaxItems, cfg.Allowed)
+	return nil
+}
+func main() {
+	if err := run(); err != nil {
+		fmt.Fprintln(os.Stderr, err)
+		os.Exit(1)
+	}
+}
--- a/examples/configuration/main_test.go
+++ b/examples/configuration/main_test.go
@@ -0,0 +1,34 @@
+package main
+
+import (
+	"os"
+	"path/filepath"
+	"reflect"
+	"testing"
+)
+
+func TestExamples(t *testing.T) {
+	var previous Config
+	for i, ext := range []string{"json", "yaml", "xml", "custom"} {
+		source := ext
+		if source == "custom" {
+			source = "json"
+		}
+		data, err := examples.ReadFile("config." + source)
+		if err != nil {
+			t.Fatal(err)
+		}
+		path := filepath.Join(t.TempDir(), "app."+ext)
+		if err = os.WriteFile(path, data, 0600); err != nil {
+			t.Fatal(err)
+		}
+		got, err := load(path)
+		if err != nil {
+			t.Fatal(err)
+		}
+		if i > 0 && !reflect.DeepEqual(previous, got) {
+			t.Fatal("format difference")
+		}
+		previous = got
+	}
+}
--- a/examples/contracts/arrays.api
+++ b/examples/contracts/arrays.api
@@ -0,0 +1,23 @@
+syntax = "v1"
+@app (defaultResponse: Common)
+response Common (
+    codeType: int32
+    successCode: 0
+    errorCode: 9999
+    messageField: msg
+    dataMode: always
+)
+@server (group: arrays)
+service arrays {
+    @handler strings
+    get /strings returns ([]string)
+    @handler integers
+    get /integers returns ([]int64)
+    @handler dynamic
+    get /dynamic returns ([]any)
+    @handler empty
+    get /empty returns ([]any)
+    @handler raw
+    @response raw
+    get /raw returns ([]bool)
+}
--- a/examples/copying/README.md
+++ b/examples/copying/README.md
@@ -0,0 +1,23 @@
+# 结构复制示例
+
+在框架仓库根目录运行 `go run ./examples/copying`；不需要数据库、网络服务或 JSON 映射配置。
+
+示例包含：可复用构造器、Go 字段改名、时间自定义转换、保留 false、深拷贝切片、同类型 Clone，以及拒绝自定义转换器返回输入的原切片。
+
+预期输出：
+
+```text
+name=sample enabled=false time=2026-01-01T00:00:00Z sourceTag=original
+clone detached: true
+shared converter rejected: true
+```
+
+测试：`go test -race ./examples/copying`。完整策略、限制与旧生成映射迁移见 [COPY.md](../../COPY.md)。
+
+独立工资三端的实际生成、HTTP 与金额用例见 [集成测试](../../cmd/go-omni/apigen/copyConsumer_test.go) 和 [公共契约](../../cmd/go-omni/apigen/testdata/composition/service.api)。框架根目录运行：
+
+```sh
+GO_OMNI_SCAFFOLD_INTEGRATION=1 go test ./cmd/go-omni/apigen -run TestCopyxThreeEndpointConsumer -count=1
+```
+
+该测试在临时独立项目中执行，三个入口共用一个普通 Go copyx helper。公共字段新增时，只修改公共契约和独立业务结构，三个入口的转换规则不增加。
--- a/examples/copying/main.go
+++ b/examples/copying/main.go
@@ -0,0 +1,61 @@
+// copying demonstrates optional Go-to-Go conversion and checked deep copying.
+package main
+
+import (
+	"errors"
+	"fmt"
+	"log"
+	"time"
+
+	"git.yuntuo.hk/k2safe/go-omni/copyx"
+)
+
+type Input struct {
+	Name      string
+	Enabled   bool
+	Tags      []string
+	CreatedAt time.Time
+}
+type View struct {
+	DisplayName string
+	Enabled     bool
+	Tags        []string
+	CreatedAt   string
+}
+
+func run() error {
+	converter, err := copyx.New(
+		copyx.WithDeepCopy(),
+		copyx.WithFieldNames[Input, View](map[string]string{"Name": "DisplayName"}),
+		copyx.WithConverter(func(v time.Time) (string, error) { return v.UTC().Format(time.RFC3339), nil }),
+	)
+	if err != nil {
+		return err
+	}
+	source := Input{Name: "sample", Enabled: false, Tags: []string{"original"}, CreatedAt: time.Date(2026, 1, 1, 0, 0, 0, 0, time.UTC)}
+	var target View
+	if err = converter.Copy(&target, source); err != nil {
+		return err
+	}
+	target.Tags[0] = "changed"
+	fmt.Printf("name=%s enabled=%t time=%s sourceTag=%s\n", target.DisplayName, target.Enabled, target.CreatedAt, source.Tags[0])
+
+	cloned, err := copyx.Clone(source)
+	if err != nil {
+		return err
+	}
+	cloned.Tags[0] = "separate"
+	fmt.Println("clone detached:", source.Tags[0] == "original")
+
+	_, err = copyx.Clone(source.Tags, copyx.WithConverter(func(v []string) ([]string, error) { return v, nil }))
+	fmt.Println("shared converter rejected:", errors.Is(err, copyx.ErrSharedReference))
+	if !errors.Is(err, copyx.ErrSharedReference) {
+		return errors.New("expected alias rejection")
+	}
+	return nil
+}
+func main() {
+	if err := run(); err != nil {
+		log.Fatal(err)
+	}
+}
--- a/examples/copying/main_test.go
+++ b/examples/copying/main_test.go
@@ -0,0 +1,9 @@
+package main
+
+import "testing"
+
+func TestExample(t *testing.T) {
+	if err := run(); err != nil {
+		t.Fatal(err)
+	}
+}
--- a/examples/httpClient/README.md
+++ b/examples/httpClient/README.md
@@ -0,0 +1,12 @@
+# HTTP Client 示例
+
+```sh
+go run ./examples/httpClient
+```
+
+只创建本机临时 HTTP 服务，不访问业务系统、数据库或公网；结束后关闭连接和监听器。
+示例创建并复用一个 Client，显式直连，配置连接池/阶段超时，通过 JSON 选项传入 Authorization 和 Accept，并按单次请求收紧响应上限。
+
+输出 `authenticated request succeeded`。示例 token 是固定演示字符串，实际项目从配置或请求上下文取得认证信息。
+
+完整参数、代理规则、流式调用、生命周期、重试边界和兼容说明见 [httpc](../../httpc/README.md)。
--- a/examples/httpClient/main.go
+++ b/examples/httpClient/main.go
@@ -0,0 +1,57 @@
+// Run with go run ./examples/httpClient. All HTTP traffic stays on loopback.
+package main
+
+import (
+	"context"
+	"encoding/json"
+	"fmt"
+	"net/http"
+	"net/http/httptest"
+	"os"
+	"time"
+
+	"git.yuntuo.hk/k2safe/go-omni/httpc"
+)
+
+type result struct {
+	Message string `json:"message"`
+}
+
+func run() error {
+	upstream := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		if r.Header.Get("Authorization") != "Bearer example-token" {
+			w.WriteHeader(http.StatusUnauthorized)
+			return
+		}
+		w.Header().Set("Content-Type", "application/json")
+		_ = json.NewEncoder(w).Encode(result{Message: "authenticated request succeeded"})
+	}))
+	defer upstream.Close()
+	client, err := httpc.New(httpc.Config{
+		Proxy:   httpc.ProxyConfig{Mode: httpc.ProxyDirect},
+		Timeout: 3 * time.Second, DialTimeout: time.Second, TLSHandshakeTimeout: time.Second,
+		ResponseHeaderTimeout: time.Second, IdleConnTimeout: 30 * time.Second,
+		MaxConnsPerHost: 16, MaxIdleConnsPerHost: 8, MaxIdleConns: 32,
+		MaxResponseBytes: 1 << 20, DisableLogging: true,
+	})
+	if err != nil {
+		return err
+	}
+	defer client.Close()
+	var output result
+	if err = client.JSON(context.Background(), http.MethodGet, upstream.URL, nil, &output,
+		httpc.WithHeader("Authorization", "Bearer example-token"),
+		httpc.WithHeaders(http.Header{"Accept": []string{"application/json"}}),
+		httpc.WithMaxResponseBytes(64<<10),
+	); err != nil {
+		return err
+	}
+	fmt.Println(output.Message)
+	return nil
+}
+func main() {
+	if err := run(); err != nil {
+		fmt.Fprintln(os.Stderr, err)
+		os.Exit(1)
+	}
+}
--- a/examples/httpClient/main_test.go
+++ b/examples/httpClient/main_test.go
@@ -0,0 +1,9 @@
+package main
+
+import "testing"
+
+func TestExample(t *testing.T) {
+	if err := run(); err != nil {
+		t.Fatal(err)
+	}
+}
--- a/examples/managedService/.goOmni/apiManifest.json
+++ b/examples/managedService/.goOmni/apiManifest.json
@@ -1,5 +1,6 @@
 {
-  "templateVersion": "v0.15.0-preview",
+  "generatorConfig": true,
+  "templateVersion": "v0.20.0-preview",
  "profile": {
    "database": "none",
    "storage": "none",
@@ -10,10 +11,11 @@
  "module": "example.com/managed",
  "entry": "api/managed.api",
  "generated": {
-    "docs/openapi.json": "68c7e9e0294bf62937aa953a44732288c51571108c922a36a72faa72c4360b5f",
+    "docs/openapi.json": "0370fd6bd6a387e2ef21f6b42b009ce66749846b8bea3d481009a34f3af039a5",
+    "internal/config/loadGen.go": "5d630b894abdbbd66ddfa7d7d30f7573fc4ff995020a32a9f9157cd4af3a5655",
    "internal/handler/appGen.go": "f5251b4dc33e2312b0bdb71ead70d2171977d851265e124f640458d705a2cc9d",
    "internal/handler/demo/handlersGen.go": "3c76d85dbe89eb5127d9d134dc625203ecf9719dd11d174c1f335691b99e1375",
-    "internal/handler/openapiGen.go": "ae9b794c63e0f3c8f9d200a5fc6977350139d4a6f00b42a26102c8630d907d03",
+    "internal/handler/openapiGen.go": "f24cab3abbb8557a3fc4dd93fba23cc0b093f3e0c944d3ba1bd5b0eeff2d96f3",
    "internal/handler/responseGen.go": "84397a502bba4777ebfa6fae3d3bc418297acab4f26b04b42e3c31b36c735399",
    "internal/handler/routesGen.go": "76c1a5b2644e75e56553dc6e9e862a63128d902dd94807ce7c8aee5491cd1e3e",
    "internal/middleware/registryGen.go": "e5f47efa57a1432765ef3419bae59dbf3b4d55b3aac0a6c935ce7a52ba6b47f4",
--- a/examples/managedService/docs/openapi.json
+++ b/examples/managedService/docs/openapi.json
--- a/examples/managedService/go.mod
+++ b/examples/managedService/go.mod
@@ -2,7 +2,7 @@ module example.com/managed

 go 1.22.0

-require git.yuntuo.hk/k2safe/go-omni v0.15.0-preview
+require git.yuntuo.hk/k2safe/go-omni v0.21.0-preview

 require (
 	github.com/gabriel-vasile/mimetype v1.4.3 // indirect
--- a/examples/managedService/internal/config/config.go
+++ b/examples/managedService/internal/config/config.go
@@ -1,11 +1,9 @@
 package config

 import (
-	"git.yuntuo.hk/k2safe/go-omni/config"
-	"git.yuntuo.hk/k2safe/go-omni/logx"
-	"os"
-	"strings"
 	"time"
+
+	"git.yuntuo.hk/k2safe/go-omni/config"
 )

 type Config struct {
@@ -23,39 +21,10 @@ func Default() Config {
 	return Config{Server: server}
 }

-// Load applies defaults -> file -> typed environment -> validation.
-// New fields automatically use GO_OMNI_<JSON_PATH>, or an explicit env tag.
-func Load(path string) (Config, error) {
-	cfg := Default()
-	var err error
-	cfg, err = config.ApplyDefaults(cfg)
-	if err != nil {
-		return Config{}, err
-	}
-	if path != "" {
-		cfg, err = config.DecodeFile(path, cfg)
-		if err != nil {
-			return Config{}, err
-		}
-	}
-	cfg, err = config.OverlayEnv(cfg, config.EnvOptions{Prefix: "GO_OMNI_"})
-	if err != nil {
-		return Config{}, err
-	}
-	// Preserve the documented framework aliases (HTTP_ADDR, LOG_LEVEL, etc).
-	cfg.Server, err = config.ApplyEnv(cfg.Server, "")
-	if err != nil {
-		return Config{}, err
-	}
-	if output := strings.TrimSpace(os.Getenv("GO_OMNI_LOG_OUTPUT")); output != "" && strings.TrimSpace(os.Getenv("GO_OMNI_LOG_FILE")) == "" {
-		cfg.Server.Log.File = ""
-		cfg.Server.Log.Rotation = logx.RotationConfig{}
-	}
-	return cfg, cfg.Validate()
-}
+// Validate checks configuration before logs or dependencies open.
 func (c Config) Validate() error {
 	if err := c.Server.Validate(); err != nil {
-		return err
+		return config.AtField("server", err)
 	}

 	return nil
--- a/examples/managedService/internal/config/loadGen.go
+++ b/examples/managedService/internal/config/loadGen.go
@@ -0,0 +1,16 @@
+// Code generated by go-omni api. DO NOT EDIT.
+package config
+
+import omniConfig "git.yuntuo.hk/k2safe/go-omni/config"
+
+// Load is maintained by the generator. Extend Config/Default/Validate in
+// config.go, or NewLoader in loader.go; do not duplicate the loading pipeline.
+func Load(path string) (Config, error) {
+	loader, err := NewLoader()
+	if err != nil {
+		return Config{}, err
+	}
+	return omniConfig.LoadProject(path, Default(), omniConfig.EnvOptions{
+		Prefix: "GO_OMNI_", Empty: "ignore", Aliases: omniConfig.ServerEnvAliases("GO_OMNI_", "server"),
+	}, loader)
+}
--- a/examples/managedService/internal/config/loader.go
+++ b/examples/managedService/internal/config/loader.go
@@ -0,0 +1,7 @@
+package config
+
+import omniConfig "git.yuntuo.hk/k2safe/go-omni/config"
+
+// NewLoader is project-owned. JSON/YAML/XML work without changes. Register
+// additional format decoders here only when the project needs them.
+func NewLoader() (*omniConfig.Loader, error) { return omniConfig.NewLoader() }
--- a/examples/managedService/internal/handler/openapiGen.go
+++ b/examples/managedService/internal/handler/openapiGen.go
--- a/examples/managedService/omni.gen.json
+++ b/examples/managedService/omni.gen.json
@@ -0,0 +1,4 @@
+{
+  "repository": "none",
+  "middleware": "handlers"
+}
--- a/httpc/README.md
+++ b/httpc/README.md
@@ -0,0 +1,153 @@
+# httpc：复用连接的 HTTP 客户端
+
+`httpc` 在标准 `net/http` 上提供独立连接池、网络阶段总超时、保守重试、请求追踪和有界 JSON 调用。普通接口可以直接带认证头调用；上传、下载、特殊协议仍使用标准 Request/Response。没有业务身份模型或全局认证信息。
+
+## 创建一次，业务重复使用
+
+```go
+client, err := httpc.New(httpc.Config{
+    Proxy: httpc.ProxyConfig{Mode: httpc.ProxyDirect},
+    Timeout: 3 * time.Second,
+    DialTimeout: time.Second,
+    TLSHandshakeTimeout: time.Second,
+    ResponseHeaderTimeout: time.Second,
+    MaxConnsPerHost: 32,
+    MaxIdleConnsPerHost: 16,
+    MaxIdleConns: 64,
+    IdleConnTimeout: 60 * time.Second,
+    MaxResponseBytes: 1 << 20,
+})
+if err != nil { return err }
+// 在 svc 初始化并持有 client，向生命周期登记 client.Close。
+// 普通独立程序也可 defer client.Close()；不要每次请求重新 New。
+
+err = client.JSON(ctx, http.MethodGet, serviceURL, nil, &result,
+    httpc.WithHeader("Authorization", "Bearer "+token),
+    httpc.WithHeaders(http.Header{"Accept": {"application/json"}}),
+)
+```
+
+Client 可并发使用。每个调用的 input/output 及其读写同步由调用方负责，不要让多个请求同时写同一个 output。
+
+直接运行 [examples/httpClient](../examples/httpClient/README.md)，只使用本地临时服务，无需业务 Token 或外部基础设施。
+
+## 代理规则
+
+| 配置 | 行为 |
+| --- | --- |
+| 不填写 Proxy | 保留被克隆 DefaultTransport 的代理策略；未改动的标准库默认使用环境代理 |
+| `Mode: httpc.ProxyEnvironment` | 明确使用 HTTP_PROXY / HTTPS_PROXY / NO_PROXY（及小写形式） |
+| `Mode: httpc.ProxyDirect` | 设置 Proxy=nil，明确直连，不受环境代理影响 |
+| `Mode: httpc.ProxyURL, URL: "http://proxy.example:8080"` | 固定代理地址，不通过 NO_PROXY 排除 |
+
+支持 http、https、socks5、socks5h；底层行为沿用 Go Transport。固定地址必须是代理 origin，不接受业务路径、查询、fragment 或无效端口。凭证可由 URL userinfo 提供，但配置错误不输出 URL/密码；不要打印整个 Config。环境代理规则由标准库读取并缓存，不提供运行时环境代理热更新。
+
+内部服务要直连，只设置 `proxy.mode: direct`，无需创建 Transport。需要自定义路由、代理认证握手等复杂逻辑时注入自己的 Transport。
+
+## 超时和连接池
+
+除原有字段外，新字段都可选：**0 保留默认行为，正数覆盖，负数拒绝**。需要明确关闭某个阶段超时、关闭 TCP keepalive 或特殊 dialer 时，使用自定义 Transport。
+
+| 字段 | 默认/含义 |
+| --- | --- |
+| Timeout | 10s；从 Do 开始，覆盖 DNS/建连、等待连接、重试、退避、响应头和读取响应体 |
+| DialTimeout | 不填时保留原 dialer；标准库默认 30s；配置后使用标准 net.Dialer |
+| DialKeepAlive | 标准 net.Dialer 的 TCP keepalive 探测间隔，标准默认 30s；不是 HTTP 空闲连接超时 |
+| TLSHandshakeTimeout | 沿用克隆 Transport；标准库默认 10s |
+| ResponseHeaderTimeout | 沿用 Transport，标准默认不单独限制；从完整发送请求后等响应头，总 Timeout 仍生效 |
+| ExpectContinueTimeout | 沿用 Transport；标准默认 1s，等待 `100-continue` 的时间 |
+| IdleConnTimeout | 沿用 Transport；标准默认 90s，只回收空闲连接 |
+| MaxConnsPerHost | 默认 64；每个目标的建连中、活动与空闲连接总上限 |
+| MaxIdleConnsPerHost | 默认等于 MaxConnsPerHost，可单独配置 |
+| MaxIdleConns | 默认 MaxConnsPerHost×2，可单独配置；所有目标合计的空闲连接上限 |
+| MaxResponseBytes | JSON 成功响应默认最多 1 MiB，最大允许配置 1 GiB；应按实际接口保持较小限额 |
+
+每主机上限最多 65536，总空闲连接最多 131072。总空闲上限可以小于各主机上限之和。MaxConnsPerHost 不等于整个进程的连接上限，也不等于 HTTP/2 的请求并发上限。
+
+配置 DialTimeout / DialKeepAlive 会创建标准 net.Dialer；未填的另一个值使用标准默认 30s。不要通过全局修改 DefaultTransport 来塞入项目的特殊拨号逻辑；请显式使用借用的 Transport。若 DefaultTransport 有自定义 TLS dialer，相关阶段覆盖会报错，避免 TLS timeout 被悄悄忽略。
+
+调用者 context 的更早截止时间优先。总超时不能抢占 Go 的 JSON 编解码或不遵守 context 的自定义 RoundTripper；计时从 Do 开始，不包括调用前的 json.Marshal。TLS 校验默认保持开启，没有新增 InsecureSkipVerify 配置。
+
+## JSON 的单次请求选项
+
+```go
+err := client.JSON(ctx, "POST", endpoint, input, &output,
+    httpc.WithHeader("Authorization", "Bearer "+token),
+    httpc.WithHeader("X-Tenant", tenant),
+    httpc.WithMaxResponseBytes(64<<10),
+)
+```
+
+- `WithHeader` 设置一个头；`WithHeaders` 支持多值 http.Header。后出现的选项覆盖同名头，不影响其他头。
+- WithHeaders 在创建选项时快照原 map，每次调用复制值。构建后修改原 map 不影响选项，选项可以并发复用；构建时原 map 的读写同步由调用方负责。
+- 不提供 Client 全局 Authorization，避免跨用户调用共享凭证。框架不会把请求头写进日志。
+- 有 input 时默认 Content-Type 为 application/json；显式请求头可覆盖。请求头名称/值会校验，拒绝 CRLF 等控制字符和歧义的大小写重复键。
+- Host、Content-Length、Transfer-Encoding、Trailer 属于请求目标/分帧控制，请用标准 Request 配合 Do；JSON 选项中不允许伪装成普通头。
+- `WithMaxResponseBytes` 是本次 JSON 的正数限额，不修改 Client 默认值，不改变 Do 的流式语义。
+
+JSON 自动关闭响应体。仅 2xx 解码；空成功响应（例如 204）保留 output 原值。非空输入使用标准 json.Unmarshal，拒绝多个 JSON 文档，类型错误保留 Go 的错误信息与行为。
+
+`output == nil` 按限额流式丢弃成功响应，不把整个 body 读进内存，也不检查 JSON 语法。响应限额按实际读取的 body 计算；标准库自动 gzip 解压后仍受上限约束。input 会先 json.Marshal 到内存，大文件上传不适合用 JSON helper。
+
+非 2xx 返回 `*httpc.StatusError`，只包含状态码，不包含错误响应体。为连接复用，只尝试读完**声明长度已知且不超过 min(32 KiB, 本次响应限额)** 的小错误体，最多等待 25ms（或更早总截止时间）；失败仍返回原 HTTP 状态。未知长度/大错误体立即关闭，优先及时返回。重试过程的错误体另受 32 KiB 大小及整体请求截止时间约束，不无界读取。
+
+## 配置文件与生成项目
+
+在项目 Config 中加一个字段：
+
+```go
+Outbound httpc.Config `json:"outbound"`
+```
+
+项目 Validate 中调用 `c.Outbound.Validate()`；创建时 New 也会验证。svc 初始化一次并通过生命周期登记 Close。文件例子：
+
+```yaml
+outbound:
+  timeout: 3s
+  proxy:
+    mode: direct
+  dialTimeout: 500ms
+  tlsHandshakeTimeout: 1s
+  responseHeaderTimeout: 1s
+  maxConnsPerHost: 32
+  maxIdleConnsPerHost: 16
+  maxIdleConns: 64
+  idleConnTimeout: 60s
+  maxResponseBytes: 1048576
+```
+
+现有统一加载入口可读取 JSON/YAML/XML，并自动覆盖 `GO_OMNI_OUTBOUND_PROXY_MODE`、`GO_OMNI_OUTBOUND_DIAL_TIMEOUT` 等环境变量。无需为每个参数手写环境解析。详见 [统一配置](../CONFIG.md)。
+
+## 标准请求、特殊 TLS 与生命周期
+
+```go
+req, err := http.NewRequestWithContext(ctx, "GET", downloadURL, nil)
+if err != nil { return err }
+req.Header.Set("Authorization", "Bearer "+token)
+res, err := client.Do(req)
+if err != nil { return err }
+defer res.Body.Close()
+// 自行判断状态，按项目要求限流/限制大小，流式写入目标；不要无界 ReadAll 大文件。
+_, err = io.Copy(destination, res.Body)
+```
+
+Do 不自动限制 body，允许下载/流式处理，调用方必须关闭。响应体消费/关闭前网络超时持续有效。
+
+`Config.Transport` 可注入任意 http.RoundTripper，适配自定义 dialer、mTLS、根证书、监控包装或测试替身。框架借用它，**不修改、不调用其 CloseIdleConnections**。代理、连接池、TLS/建连阶段配置不能同时填入，避免无效配置；总 Timeout、JSON 限额、框架重试/日志仍有效。借用实现必须遵守标准请求和 body 所有权、并发及 context 约定。
+
+`Close` 幂等：拒绝新调用，关闭自有池的空闲连接，不主动打断已开始的请求。服务关闭应先排空 HTTP/后台调用，再关闭 Client；它不是后台 drain 的替代品。生成项目可通过 svc 的生命周期登记清理。
+
+## 重试、日志与兼容
+
+MaxRetries 默认 0，最多 5。仅可重放的 GET/HEAD/OPTIONS 对网络错误、429/502/503/504 做框架重试。POST/PUT/PATCH/DELETE 不自动做应用层重试。标准库或自定义 Transport 自己的重放规则仍可能生效，不能承诺业务“恰好执行一次”。
+
+Backoff 默认 100ms，MaxBackoff 默认 2s，采用指数退避与抖动。Retry-After 要求等待超过 MaxBackoff 时返回当前响应，不提前请求；总截止时间限制全部尝试。成功或无重试的调用不计算退避。
+
+不跟随重定向，避免自动向其他地址转发认证信息；3xx 由调用者判断。默认传递 context 中的 X-Request-ID，显式请求头优先。日志只包含 method、hostname、status、attempt、收到响应头的耗时等，不打印路径、查询、用户名密码、认证头或响应体；标准 net/http 返回的 URL 错误可能携带地址，项目不要把 URL 中的密钥当作安全日志字段。
+
+v0.21 兼容说明：
+
+- 原来的 JSON 五参数直接调用继续有效；新方法末尾增加 `...httpc.RequestOption`，自行定义的 interface/方法值类型需要同步签名。
+- 原默认代理、总超时、重试、池大小和成功响应含义保留；新字段未设置时不改变它们。
+- `Transport` 与显式池/代理/阶段参数混用现在报错；此前 MaxConnsPerHost 在自定义 Transport 下实际被忽略。迁移时把参数放到自己的 Transport，或删掉 Transport 改用内置配置。
+- 没有移除 Do、JSON、StatusError 或自定义 Transport，没有引入新第三方依赖。
--- a/httpc/benchmark_test.go
+++ b/httpc/benchmark_test.go
@@ -0,0 +1,100 @@
+package httpc
+
+import (
+	"context"
+	"io"
+	"net/http"
+	"net/http/httptest"
+	"strings"
+	"testing"
+)
+
+type benchmarkTransport struct {
+	payload string
+	status  int
+}
+
+func (t benchmarkTransport) RoundTrip(r *http.Request) (*http.Response, error) {
+	if r.Body != nil {
+		_ = r.Body.Close()
+	}
+	return &http.Response{StatusCode: t.status, Header: make(http.Header), Body: io.NopCloser(strings.NewReader(t.payload)), ContentLength: int64(len(t.payload)), Request: r}, nil
+}
+func BenchmarkHTTPClient(b *testing.B) {
+	for _, size := range []int{128, 4096, 65536} {
+		for _, discard := range []bool{false, true} {
+			label := map[int]string{128: "128B", 4096: "4KiB", 65536: "64KiB"}[size]
+			if discard {
+				label += "/discard"
+			} else {
+				label += "/decode"
+			}
+			b.Run(label, func(b *testing.B) {
+				c, err := New(Config{Transport: benchmarkTransport{`{"value":"` + strings.Repeat("x", size) + `"}`, 200}, DisableLogging: true})
+				if err != nil {
+					b.Fatal(err)
+				}
+				defer c.Close()
+				var output struct {
+					Value string `json:"value"`
+				}
+				var target any = &output
+				if discard {
+					target = nil
+				}
+				b.ReportAllocs()
+				b.ResetTimer()
+				for i := 0; i < b.N; i++ {
+					if err := c.JSON(context.Background(), "GET", "http://example.invalid/item", nil, target); err != nil {
+						b.Fatal(err)
+					}
+				}
+			})
+		}
+	}
+	b.Run("Do", func(b *testing.B) {
+		c, _ := New(Config{Transport: benchmarkTransport{"", 200}, DisableLogging: true})
+		defer c.Close()
+		r, _ := http.NewRequest("GET", "http://example.invalid/item", nil)
+		b.ReportAllocs()
+		b.ResetTimer()
+		for i := 0; i < b.N; i++ {
+			res, err := c.Do(r)
+			if err != nil {
+				b.Fatal(err)
+			}
+			res.Body.Close()
+		}
+	})
+}
+func BenchmarkHTTPPool(b *testing.B) {
+	for _, status := range []int{200, 401} {
+		b.Run(http.StatusText(status), func(b *testing.B) {
+			s := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) { w.WriteHeader(status); io.WriteString(w, `{"ok":true}`) }))
+			defer s.Close()
+			c, _ := New(Config{DisableLogging: true})
+			defer c.Close()
+			b.ReportAllocs()
+			b.ResetTimer()
+			for i := 0; i < b.N; i++ {
+				err := c.JSON(context.Background(), "GET", s.URL, nil, nil)
+				if status == 200 && err != nil {
+					b.Fatal(err)
+				}
+			}
+		})
+	}
+}
+
+func BenchmarkHTTPHeaders(b *testing.B) {
+	c, _ := New(Config{Transport: benchmarkTransport{`{"ok":true}`, 200}, DisableLogging: true})
+	defer c.Close()
+	option := WithHeaders(http.Header{"Authorization": []string{"Bearer example"}, "X-Request-Id": []string{"example-request"}})
+	b.ReportAllocs()
+	b.ResetTimer()
+	for i := 0; i < b.N; i++ {
+		if err := c.JSON(context.Background(), "GET", "http://example.invalid", nil, nil, option); err != nil {
+			b.Fatal(err)
+		}
+	}
+}
--- a/httpc/client.go
+++ b/httpc/client.go
@@ -3,9 +3,7 @@
 package httpc

 import (
-	"bytes"
 	"context"
-	"encoding/json"
 	"errors"
 	"fmt"
 	"io"
@@ -22,18 +20,6 @@ import (
 var ErrClosed = errors.New("httpc: closed")
 var ErrResponseTooLarge = errors.New("httpc: response exceeds limit")

-type Config struct {
-	Timeout          time.Duration     `json:"timeout"`
-	MaxRetries       int               `json:"maxRetries"`
-	Backoff          time.Duration     `json:"backoff"`
-	MaxBackoff       time.Duration     `json:"maxBackoff"`
-	MaxConnsPerHost  int               `json:"maxConnsPerHost"`
-	MaxResponseBytes int64             `json:"maxResponseBytes"`
-	DisableRequestID bool              `json:"disableRequestId"`
-	DisableLogging   bool              `json:"disableLogging"`
-	Transport        http.RoundTripper `json:"-"` // Borrowed. The caller owns its lifecycle.
-}
-
 type Client struct {
 	config Config
 	client *http.Client
@@ -41,43 +27,19 @@ type Client struct {
 	closed atomic.Bool
 }

+// New creates a reusable client. Close it after callers and response streams drain.
 func New(cfg Config) (*Client, error) {
-	if cfg.Timeout < 0 || cfg.Backoff < 0 || cfg.MaxBackoff < 0 || cfg.MaxRetries < 0 || cfg.MaxRetries > 5 || cfg.MaxConnsPerHost < 0 || cfg.MaxResponseBytes < 0 {
-		return nil, errors.New("httpc: invalid configuration")
+	normalized, err := normalizeConfig(cfg)
+	if err != nil {
+		return nil, err
 	}
-	if cfg.Timeout == 0 {
-		cfg.Timeout = 10 * time.Second
-	}
-	if cfg.Backoff == 0 {
-		cfg.Backoff = 100 * time.Millisecond
-	}
-	if cfg.MaxBackoff == 0 {
-		cfg.MaxBackoff = 2 * time.Second
-	}
-	if cfg.Backoff > cfg.MaxBackoff {
-		return nil, errors.New("httpc: backoff exceeds maxBackoff")
-	}
-	if cfg.MaxConnsPerHost == 0 {
-		cfg.MaxConnsPerHost = 64
-	}
-	if cfg.MaxResponseBytes == 0 {
-		cfg.MaxResponseBytes = 1 << 20
-	}
-	if cfg.MaxResponseBytes > 1<<30 || cfg.MaxConnsPerHost > 65536 {
-		return nil, errors.New("httpc: response or connection limit exceeds supported capacity")
-	}
-	c := &Client{config: cfg}
+	c := &Client{config: normalized}
 	transport := cfg.Transport
 	if transport == nil {
-		// Own a private pool; never mutate the process-wide DefaultTransport.
-		base, ok := http.DefaultTransport.(*http.Transport)
-		if !ok {
-			return nil, errors.New("httpc: provide Transport when DefaultTransport is replaced")
+		c.owned, err = ownedTransport(normalized)
+		if err != nil {
+			return nil, err
 		}
-		c.owned = base.Clone()
-		c.owned.MaxConnsPerHost = cfg.MaxConnsPerHost
-		c.owned.MaxIdleConnsPerHost = cfg.MaxConnsPerHost
-		c.owned.MaxIdleConns = cfg.MaxConnsPerHost * 2
 		transport = c.owned
 	}
 	c.client = &http.Client{Transport: transport, CheckRedirect: func(*http.Request, []*http.Request) error { return http.ErrUseLastResponse }}
@@ -114,7 +76,10 @@ func (c *Client) Do(request *http.Request) (*http.Response, error) {
 	}
 	replayable := (base.Method == "" || base.Method == "GET" || base.Method == "HEAD" || base.Method == "OPTIONS") && (base.Body == nil || base.Body == http.NoBody || base.GetBody != nil)
 	for attempt := 0; ; attempt++ {
-		req := base.Clone(ctx)
+		req := base
+		if attempt > 0 {
+			req = base.Clone(ctx)
+		}
 		if attempt > 0 && base.Body != nil && base.Body != http.NoBody {
 			body, err := base.GetBody()
 			if err != nil {
@@ -133,23 +98,9 @@ func (c *Client) Do(request *http.Request) (*http.Response, error) {
 			logx.InfoContext(ctx, "http.client", "method", req.Method, "host", req.URL.Hostname(), "status", status, "attempt", attempt+1, "durationMs", time.Since(started).Seconds()*1000, "failed", err != nil)
 		}
 		retry := replayable && attempt < c.config.MaxRetries && ctx.Err() == nil && (err != nil || status == 429 || status == 502 || status == 503 || status == 504)
-		delay := c.config.Backoff
-		for i := 0; i < attempt && delay < c.config.MaxBackoff; i++ {
-			if delay > c.config.MaxBackoff/2 {
-				delay = c.config.MaxBackoff
-			} else {
-				delay *= 2
-			}
-		}
-		if response != nil && response.Header.Get("Retry-After") != "" {
-			if value, ok := retryAfter(response.Header.Get("Retry-After")); ok {
-				delay = value
-			}
-		} else if delay > 1 {
-			delay = delay/2 + time.Duration(rand.Int63n(int64(delay/2)+1))
-		}
-		if delay > c.config.MaxBackoff {
-			retry = false
+		var delay time.Duration
+		if retry {
+			delay, retry = c.retryDelay(attempt, response)
 		}
 		if !retry {
 			if err != nil {
@@ -160,9 +111,7 @@ func (c *Client) Do(request *http.Request) (*http.Response, error) {
 			return response, nil
 		}
 		if response != nil {
-			if response.ContentLength >= 0 && response.ContentLength <= 32<<10 {
-				_, _ = io.Copy(io.Discard, response.Body)
-			}
+			drainSmallBody(response, 32<<10)
 			_ = response.Body.Close()
 		}
 		timer := time.NewTimer(delay)
@@ -204,48 +153,6 @@ type StatusError struct{ StatusCode int }

 func (e *StatusError) Error() string { return fmt.Sprintf("httpc: HTTP status %d", e.StatusCode) }

-// JSON bounds response memory, closes the body, and decodes only 2xx responses.
-// Error bodies, URLs, credentials and query strings are not included in logs.
-func (c *Client) JSON(ctx context.Context, method, url string, input, output any) error {
-	if ctx == nil {
-		return errors.New("httpc: nil context")
-	}
-	var body io.Reader
-	if input != nil {
-		data, err := json.Marshal(input)
-		if err != nil {
-			return err
-		}
-		body = bytes.NewReader(data)
-	}
-	request, err := http.NewRequestWithContext(ctx, method, url, body)
-	if err != nil {
-		return err
-	}
-	if input != nil {
-		request.Header.Set("Content-Type", "application/json")
-	}
-	response, err := c.Do(request)
-	if err != nil {
-		return err
-	}
-	defer response.Body.Close()
-	if response.StatusCode < 200 || response.StatusCode >= 300 {
-		return &StatusError{StatusCode: response.StatusCode}
-	}
-	data, err := io.ReadAll(io.LimitReader(response.Body, c.config.MaxResponseBytes+1))
-	if err != nil {
-		return err
-	}
-	if int64(len(data)) > c.config.MaxResponseBytes {
-		return ErrResponseTooLarge
-	}
-	if output == nil || len(bytes.TrimSpace(data)) == 0 {
-		return nil
-	}
-	return json.Unmarshal(data, output)
-}
-
 func (c *Client) Close() error {
 	c.closed.Store(true)
 	if c.owned != nil {
@@ -253,3 +160,34 @@ func (c *Client) Close() error {
 	}
 	return nil
 }
+
+// retryDelay is deliberately outside the success path: no jitter/random work
+// for calls that cannot or do not need to retry.
+func (c *Client) retryDelay(attempt int, response *http.Response) (time.Duration, bool) {
+	delay := c.config.Backoff
+	for i := 0; i < attempt && delay < c.config.MaxBackoff; i++ {
+		if delay > c.config.MaxBackoff/2 {
+			delay = c.config.MaxBackoff
+		} else {
+			delay *= 2
+		}
+	}
+	if response != nil {
+		if value, ok := retryAfter(response.Header.Get("Retry-After")); ok {
+			return value, value <= c.config.MaxBackoff
+		}
+	}
+	if delay > 1 {
+		delay = delay/2 + time.Duration(rand.Int63n(int64(delay/2)+1))
+	}
+	return delay, delay <= c.config.MaxBackoff
+}
+
+// Drain only a known small error body. Unknown/large bodies are closed promptly;
+// never allocate or consume an unbounded error document just to retain a pool slot.
+func drainSmallBody(response *http.Response, limit int64) {
+	limit = min(limit, 32<<10)
+	if response.Body != nil && response.ContentLength >= 0 && response.ContentLength <= limit {
+		_, _ = io.Copy(io.Discard, io.LimitReader(response.Body, limit+1))
+	}
+}
--- a/Show More
+++ b/Show More
Author	SHA1	Message	Date
k2safe	96e7d9629b	feat: simplify HTTP client proxy pools and authenticated JSON calls	2026-09-26 15:28:19 +08:00
k2safe	068e85132f	test: record remote configuration release acceptance	2026-09-26 14:49:28 +08:00
k2safe	c60841f901	feat: unify generated configuration loading and extensible decoders	2026-09-26 14:47:33 +08:00
k2safe	91a6beb2f3	test: verify remote copyx release and update usage reference	2026-09-25 17:31:48 +08:00
k2safe	fd83235ce7	feat: replace mapping generation with checked copy utilities	2026-09-25 17:27:28 +08:00
k2safe	ad9257d202	test: record remote nullable mapping release acceptance	2026-09-25 13:58:45 +08:00
k2safe	4563a6354f	feat: release nullable mappings and split mapping configuration	2026-09-25 13:56:44 +08:00
k2safe	5fc82509a1	test: record remote generation experience release acceptance	2026-09-25 12:45:29 +08:00
k2safe	8b588a24cd	feat: release generic composition mapping and middleware factories	2026-09-25 12:43:34 +08:00
k2safe	8493f9dae9	test: record remote contract tooling release acceptance	2026-09-25 02:23:58 +08:00
k2safe	64e3bd6cfc	feat: support primitive response arrays and shared catalog tooling	2026-09-25 02:22:24 +08:00
k2safe	1f2d8b6a6a	test: record remote phased lifecycle release acceptance	2026-09-25 00:37:21 +08:00