存储

枢纽：ctx.storage

Storage（签名）是汇合点，不是存储本体。ctx.storage.backend 是一张名称 → 后端的表：多个后端并排保持挂载，哪个后端服务哪个消费方由该消费方自己的配置决定（即领域层的路由表），绝不是枢纽全局的选择。register(name, backend) 返回 disposer；重复名称与查找未知名称都抛出 StorageError。dispose（资源释放）只注销名称——由拥有它的插件在注销之后自行关闭后端。每个后端插件还会发布一个仅用于生命周期的服务键（storageBackendServiceKey(name)），数据形式提供方注入它，使自身激活不会与后端注册发生竞态。

数据形式以一张可合并扩展的键 map 挂载到枢纽上：

/**
 * Data forms mountable on the hub, keyed by form name. Form owners extend
 * this map via declaration merging (the domain layer merges
 * `domain: DomainFacility`) and mount the facility in their `apply`.
 */
interface StorageForms {}

mount(form, facility) 是一个 effect，其 disposer 负责卸载；对同一键的第二次挂载抛出 duplicate-mount。form(form) 解析已挂载的 facility，在拥有插件加载之前抛出 form-not-mounted——组合方应据此安排插件顺序，而不是静默推迟。领域层合并 domain: DomainFacility，因此 ctx.storage.domain 与 ctx.storageDomain 是同一个对象。

后端约定

/**
 * One registered backend. A backend owns exactly one medium and shares its
 * lifecycle across all facets; facets are optional members — a backend that
 * cannot serve a data kind simply omits it, and resolution fails loud instead.
 */
interface StorageBackend {
  /** Key-value operations; absent when this backend cannot serve them. */
  readonly kv?: KvFacet

  /**
   * Drain in-flight writes across all open units and release the medium.
   * Idempotent; concurrent and repeated calls resolve once teardown finishes.
   * @returns resolution after the medium is released.
   */
  close(): Promise<void>
}

一个后端拥有一个介质（一棵文件树的根目录、一个数据库文件），并提供可选的操作组；目前 kv 是唯一一组。KvFacet.open(descriptor) 打开一个具名 unit——KvUnitDescriptor 携带名称、格式版本、表名清单，以及是否存在全局单例 slot——并返回提供 loadAll、putRecord、deleteRecord、setGlobal 和 close 的 KvUnit。unit 名与表名必须匹配 UNIT_NAME_RE（既可安全用作文件名，也可安全用作 SQL 标识符片段）；记录键是任意字符串，绝不进入文件路径。unit 不对并发写入做串行化——顺序由调用方负责——但每次单独调用在介质上都是原子的，且 resolve 后即已持久。介质上记录的版本与之不同时拒绝 version-mismatch；无法按该 unit 解析的介质拒绝 malformed-medium（不做迁移：预发布立场）。backend.ts 是逐条款的规范性约定，tests/contract.ts 中的共享一致性套件会针对每个后端检查每项条款。json 后端以原子方式为每个 unit 整文件重新发布一份人类可读文件；sqlite 后端在单个数据库中每行存储一份文档，用于频繁更新的数据。

声明领域

领域由其拥有包声明一次，形式是一个 spec 对象——它是该领域的身份、布局和记录 schema 的单一来源（schema 用 zod 编写，因此 z.infer 让消费方类型无需重复声明）：

/** Static declaration of one domain: identity, version, and record layout. */
interface DomainSpec {
  /** Domain name; must match `UNIT_NAME_RE` (doubles as the backend unit name). */
  readonly name: string
  /** Domain format version; a medium stamped with a different version rejects at open. */
  readonly version: number
  /** Optional global singleton slot. */
  readonly global?: DomainGlobalSpec<unknown>
  /** Table declarations keyed by table name; each name must match `UNIT_NAME_RE`. */
  readonly tables: Record<string, DomainTableSpec>
}

defineDomain(spec) 固定 spec 的字面量类型，并在拥有方的模块加载时、任何介质被触碰之前就明确报错：领域名或表名不匹配 UNIT_NAME_RE、版本不是非负整数、global schema 接受 null，这些都会抛出（null 是介质的「从未写入」哨兵值，可空的 global 一旦存储就无法往返还原）。domainTable<K, V>(schema) 声明一张表，其键类型是仅存在于编译期的 phantom 类型（通常是品牌化 id）；descriptorOf(spec) 投影出面向后端的 unit 描述符。

打开的领域

/** One open domain, typed by its spec. */
interface Domain<S extends DomainSpec> {
  /** Domain name from the spec. */
  readonly name: string
  /** Global singleton handle; a spec without `global` has no usable handle (`never`). */
  readonly global: DomainGlobalHandleOf<S>
  /**
   * Resolve one declared table handle. Handles are stable — repeated calls
   * return the same instance.
   * @param name - Declared table name.
   * @returns the typed table handle.
   */
  table<N extends keyof S['tables'] & string>(name: N): KvTable<TableKeyOf<S, N>, TableValueOf<S, N>>

  /**
   * Close this domain: reject new writes immediately, drain already-queued
   * writes (their events still emit), release the backend unit, then free
   * the domain name for a later open. Idempotent — repeated calls share one
   * teardown. The consumer owns this call (typically as its own `ctx.effect`
   * disposer); the facility closes any domain left open when it unmounts.
   * @returns resolution after the unit is released.
   */
  close(): Promise<void>
}

读取是同步的，来自权威的内存态：KvTable 暴露 get/entries/keys/size（快照迭代器，在排队写入落地期间保持稳定），global 句柄的 get() 在第一次 set 将 slot 物化到介质之前一直返回 spec 的 initial。每次写入——put、delete、update、global.set——都在同一条逐领域写链上排队，先在后端完成持久化，再更新内存，最后发出 domain/changed；后端写入被拒时内存原样不动，因此读取绝不会偏离介质。update(key, fn) 在其写链 slot 上是一次原子的读-改-写（键缺失时拒绝 missing-key）；delete 一个不存在的键 resolve 为 false，不产生写入也不产生事件。返回的记录就是存储的对象本身，不是副本——请经 put/update 整体替换，绝不要就地修改。

领域 facility：ctx.storageDomain

DomainFacility（签名）在经过路由的后端之上打开已声明的领域。路由是领域插件的配置，绝不属于枢纽：backend 指定必填的默认路由，routes 按领域名逐个覆盖。open(spec) 按严格顺序执行，每一步失败都使整个调用失败：拒绝已打开或仍在关闭中的名称（already-open），解析路由（backend-not-found），要求后端具备 kv facet（facet-unsupported），打开 unit（后端的 version-mismatch/malformed-medium 原样透传），并按 spec 的 zod schema 校验每条已存储记录和 global（invalid-record，附带出错的表与键）。调用方拥有返回的句柄，并用 Domain.close() 释放它；插件卸载时仍处于打开状态的领域由 facility 负责关闭，已关闭领域的名称只有在拆除完全结束后才释放出来供重新打开。get(name) 是无类型的诊断查找，命中的是每个类型化句柄背后包内私有的 DomainImpl 运行时；closeAll() 是卸载路径。

变更事件：domain/changed

每次持久写入都发出一个事件，严格发生在后端确认持久性之后，顺序遵循该领域的写链（事件条目）：

/** Shared location fields of one durable domain change. */
interface DomainChangedBase {
  /** Owning domain name. */
  readonly domain: string
  /** Table name; `''` for a global-singleton write. */
  readonly table: string
  /** Record key; `''` for a global-singleton write. */
  readonly key: string
}

/** One durable domain change; a closed union — switch on `operation`. */
type DomainChanged = DomainChangedPut | DomainChangedDeleted

put（插入、覆写和 global 写入）在 value 中携带新快照——绝不携带旧值；需要做差异比较的消费方自行保留上一份快照。deleted 是不携带值的墓碑。该事件是通知，不是事务参与者：发出时提交点已经过去，因此同步抛出的监听器会被兜住并记录一条警告，而不会让已经持久的写入被拒绝；发出的值等于发出时刻的内存态。该事件仅限进程内；跨进程的变更推送是一项已记录的限制（包 README）。

Cordis API

Generated from source by scripts/gen-cordis-catalog.ts (verified fresh by pnpm run verify-cordis-catalog in doc-sync; regenerate with pnpm run gen-cordis-catalog) — this section is byte-identical in both language sides of the page. Signature blocks use a ts cordis-catalog fence and keep the original source JSDoc; dispatch modes are defined in the primer, and the framework-inherited ctx API lives in cordis-api/inherited.md.

ctx.storage — Storage

The storage hub service. Backends register under backend; data forms mount under their StorageForms key and are reached as ctx.storage.<form>.

/**
 * Mount a data-form facility on the hub. Mounting is an effect: the
 * returned disposer unmounts the form.
 * @param form - Form key declared in {@link StorageForms}.
 * @param facility - The facility instance to expose.
 * @returns the disposer that unmounts the form.
 */
mount<K extends keyof StorageForms>(form: K, facility: StorageForms[K]): () => void

/**
 * Resolve a mounted data form.
 * @param form - Form key declared in {@link StorageForms}.
 * @returns the mounted facility.
 */
form<K extends keyof StorageForms>(form: K): StorageForms[K]

Source: packages/storage/storage/src/index.ts:47

ctx.storageDomain — DomainFacility

The mounted domain facility. Opens declared domains over routed backends; one facility instance owns the open-domain table and enforces single-open per domain name.

/**
 * Open one declared domain. Steps, each failing the whole call: reject a
 * name that is already open (`already-open`); resolve the backend route
 * (`backend-not-found` passes through from the hub); require its `kv` facet
 * (`facet-unsupported`); open the unit projected from the spec (backend
 * `version-mismatch`/`malformed-medium` pass through); load and validate
 * every stored record against the spec's zod schemas (`invalid-record`
 * with the offending table and key); construct the domain.
 *
 * Lifecycle: the CALLER owns the returned handle and closes it via
 * `Domain.close()` (typically as its own `ctx.effect` disposer) — the
 * facility does not tie the domain to any consumer fiber. Domains still
 * open when the facility unmounts are closed by the plugin disposer.
 * @param spec - The domain declaration, typically from `defineDomain`.
 * @returns the opened domain handle, typed by the spec.
 */
async open<S extends DomainSpec>(spec: S): Promise<Domain<S>>

/**
 * Look up an open domain by name, untyped. Diagnostic surface (the package
 * invariant cross-checks change events against live domain state); typed
 * consumers hold the handle returned by {@link open}.
 * @param name - Domain name.
 * @returns the open domain runtime, or `undefined` when not open.
 */
get(name: string): DomainImpl | undefined

/**
 * Close every domain still open on this facility. The unmount path for
 * consumers that never called `Domain.close()` themselves; closing is
 * idempotent, so double-closing an already-closed domain is harmless.
 * @returns resolution after every unit is released.
 */
async closeAll(): Promise<void>

Source: packages/storage/storage-domain/src/index.ts:69

domain/* events

domain/changed — emit

A domain record or the global singleton changed, emitted once per write strictly after the backend acknowledged durability. Events of one domain arrive in its write-chain order.

/**
 * A domain record or the global singleton changed, emitted once per write
 * strictly after the backend acknowledged durability. Events of one
 * domain arrive in its write-chain order.
 * @param change - domain, table (`''` for global), key (`''` for global),
 * operation discriminant, and on `put` the new snapshot.
 * @mode emit
 */
'domain/changed'(change: DomainChanged): void

Source: packages/storage/storage-domain/src/events.ts:46