Merge pull request 'feat: add module HTTP transport' (#12) from phase-5/module-http-transport into main

Reviewed-on: http://git.riverofglorymn.org/River_of_Glory_Church/Ekklesia/pulls/12
2026-07-25 15:44:40 +00:00
parent c9cf1f08e3 300f98c29d
commit 9c9ede0418
26 changed files with 3874 additions and 160 deletions
@@ -61,12 +61,25 @@ enforceable and grantable through the exact same `requirePermission` middleware
 claimable by a module. `pnpm doctor` and `pnpm modules:validate` both validate permission
 composition. Installing, removing, or editing a module currently requires an API restart; removing
 one makes its permission unavailable to new checks and new grants without deleting or revoking any
-historical grant or audit row. Module HTTP route registration and relationship-derived grant
-creation remain later work. See
+historical grant or audit row. See
 [Authorization](docs/development/authorization.md#module-permission-composition),
 [Module development](docs/module-development/README.md), and
 [ADR 0014](docs/architecture/decisions/0014-module-permission-declarations-and-platform-registry.md).

+Phase 5B mounts a module's own HTTP routes in production. A module registers framework-neutral
+Fetch (`Request`/`Response`) route handlers during its existing `register` hook; Core collects them
+into an immutable snapshot alongside its capabilities, and `apps/api` discovers modules exactly
+once, starts the module runtime from that same discovered inventory, and mounts its published
+routes under `/api/v1/modules/<module-id>` — after every module has registered and started
+successfully, so no request can reach a module before startup completes. Every route is enforced
+through the identical `requirePermission` middleware and composed permission registry Core's own
+routes use (a module can never supply its own baseline), state-changing methods require a trusted
+`Origin`, and a handler failure or non-`Response` return becomes a fixed, sanitized `500` — never a
+raw error, stack, path, or permission id. Relationship-derived grant creation remains later work.
+See [API](docs/development/api.md#module-http-routes),
+[Module development](docs/module-development/README.md#http-routes), and
+[ADR 0014](docs/architecture/decisions/0014-module-permission-declarations-and-platform-registry.md#deferred).
+
 ## Quick start

 Prerequisites: Node.js 24 LTS, pnpm 11.12, and Docker with Compose.
@@ -1,4 +1,4 @@
-import { isAuthenticatedPrincipal } from "@ekklesia/contracts";
+import { isAuthenticatedPrincipal, type RegisteredModuleHttpRoute } from "@ekklesia/contracts";
 import type {
  AuthorizationEvaluator,
  AuthorizationStore,
@@ -6,26 +6,33 @@ import type {
 } from "@ekklesia/core/authorization";
 import { type EkklesiaIdentityRuntime, IdentityRuntimeError } from "@ekklesia/core/identity";
 import { Hono } from "hono";
-import type { Context } from "hono";
+import type { Context, MiddlewareHandler } from "hono";
 import { cors } from "hono/cors";
 import { createGrantsRoutes } from "./grants-routes.js";
+import { canonicalizeVaryHeader, mountModuleHttpRoutes } from "./module-http-routes.js";

 export interface CreateApiAppAuthorizationOptions {
  readonly evaluator: AuthorizationEvaluator;
  /** The complete platform permission registry (Core's own declarations plus every installed
   * module's) — always the caller-composed registry `startApi` produces via
-   * `composeStartupPermissionRegistry`, never a Core-only fallback constructed here. */
+   * `prepareStartupModuleInventory`, never a Core-only fallback constructed here. */
  readonly registry: PermissionRegistry;
  readonly store: AuthorizationStore;
 }

 export interface CreateApiAppOptions {
  readonly authorization: CreateApiAppAuthorizationOptions;
+  /** The started module runtime's published, immutable route snapshot — always the caller-started
+   * runtime's exact `routes` (`startDiscoveredModuleRuntime`, `apps/api/src/server.ts`), mounted in
+   * publication order under `/api/v1/modules/<module-id>`. Required rather than defaulted so a
+   * caller not exercising modules must say so explicitly (an empty frozen array), never rely on an
+   * implicit fallback. */
+  readonly moduleRoutes: readonly RegisteredModuleHttpRoute[];
  readonly runtime: EkklesiaIdentityRuntime;
  /** Exact allowed browser origins. Never a wildcard; combined with `credentials: true`, only an
   * exact, reflected match is ever returned in `Access-Control-Allow-Origin`. Also the trusted set
-   * `requireTrustedOrigin` checks for grant-mutation routes — there is no second, competing origin
-   * configuration. */
+   * `requireTrustedOrigin` checks for grant- and module-route-mutation routes — there is no second,
+   * competing origin configuration. */
  readonly trustedOrigins: readonly string[];
 }

@@ -36,9 +43,52 @@ function sanitizedErrorResponse(c: Context, error: unknown, status: 500 | 503) {
 }

 /**
- * Pure Hono application factory: no I/O, no environment reads, no process side effects. Suitable
- * for unit and integration tests via `app.fetch` directly, with a fully injected identity runtime
- * and authorization evaluator/store standing in for real Better Auth/PostgreSQL where appropriate.
+ * Hono's own `cors()` unconditionally appends its own "Vary: Origin" after every response with a
+ * dynamic-function `origin` — including one that already has its own `Vary` (module responses
+ * force `Origin`/`Cookie`; `/api/v1/principal` sets `Origin, Cookie` directly; an `OPTIONS`
+ * preflight sets its own) — so the header `cors()` itself leaves behind can still be an invalid
+ * combined "*, Origin" or contain a case-different duplicate. This wraps `middleware` and
+ * canonicalizes whatever `Vary` remains only *after* it has fully finished, using
+ * `canonicalizeVaryHeader` — the same shared parsing/dedup primitive `mergedVaryHeader` (module
+ * responses) builds on, so there is one implementation to keep in sync, not two that could diverge
+ * — but never `mergedVaryHeader` itself: this boundary wraps *every* response, `OPTIONS` preflights
+ * included, and must never inject `Origin`/`Cookie` onto a response that never had them, only
+ * de-duplicate what is already there. Two return shapes have to be handled: a normal request lets
+ * `middleware` call `next()` and mutate `c.res` in place, so the fix-up goes through `c.header()`
+ * (reassigning `c.res` directly triggers Hono's own header-preserving merge and would silently
+ * restore the uncanonicalized value); an `OPTIONS` preflight makes `cors()` return a new `Response`
+ * directly without ever touching `c.res`, so the fix-up mutates that returned response's headers
+ * instead. Neither path reads or clones the response body, so a streaming body is untouched either
+ * way. Status, body, content type, ordinary headers, authorization, trusted-origin behavior, and
+ * route ordering are all unaffected — only the final `Vary` value changes.
+ */
+function withCanonicalVary(middleware: MiddlewareHandler): MiddlewareHandler {
+  return async (c, next) => {
+    const result = await middleware(c, next);
+    if (result instanceof Response) {
+      const existingVary = result.headers.get("Vary");
+      if (existingVary !== null) {
+        result.headers.set("Vary", canonicalizeVaryHeader(existingVary));
+      }
+      return result;
+    }
+    const existingVary = c.res.headers.get("Vary");
+    if (existingVary !== null) {
+      c.header("Vary", canonicalizeVaryHeader(existingVary));
+    }
+    return result;
+  };
+}
+
+/**
+ * Pure Hono application factory: no I/O, no environment reads, no process side effects, and it
+ * never invokes a module route handler while composing routes. Suitable for unit and integration
+ * tests via `app.fetch` directly, with a fully injected identity runtime and authorization
+ * evaluator/store standing in for real Better Auth/PostgreSQL where appropriate. Synchronously
+ * throws `ModuleRouteConfigurationError` (`./module-http-routes.js`) if `moduleRoutes` and
+ * `authorization.registry` are inconsistent — a route naming a permission the registry does not
+ * register, which should never happen since both derive from the same discovered inventory, but is
+ * checked explicitly rather than silently mounting an unenforceable route.
 */
 export function createApiApp(options: CreateApiAppOptions): Hono {
  const { runtime } = options;
@@ -46,13 +96,15 @@ export function createApiApp(options: CreateApiAppOptions): Hono {

  const app = new Hono();

-  const corsMiddleware = cors({
-    allowHeaders: ["Content-Type"],
-    allowMethods: ["GET", "POST", "OPTIONS"],
-    credentials: true,
-    maxAge: 600,
-    origin: (origin) => (origin && allowedOrigins.has(origin) ? origin : undefined),
-  });
+  const corsMiddleware = withCanonicalVary(
+    cors({
+      allowHeaders: ["Content-Type"],
+      allowMethods: ["GET", "POST", "PUT", "PATCH", "DELETE", "OPTIONS"],
+      credentials: true,
+      maxAge: 600,
+      origin: (origin) => (origin && allowedOrigins.has(origin) ? origin : undefined),
+    }),
+  );
  app.use("/api/auth/*", corsMiddleware);
  app.use("/api/v1/*", corsMiddleware);

@@ -91,6 +143,13 @@ export function createApiApp(options: CreateApiAppOptions): Hono {
    }),
  );

+  mountModuleHttpRoutes(app, options.moduleRoutes, {
+    evaluator: options.authorization.evaluator,
+    registry: options.authorization.registry,
+    runtime,
+    trustedOrigins: allowedOrigins,
+  });
+
  app.notFound((c) => {
    c.header("Cache-Control", "no-store");
    return c.json({ code: "NOT_FOUND" }, 404);
@@ -0,0 +1,209 @@
+import type {
+  ModuleId,
+  ModuleRouteHandlerContext,
+  RegisteredModuleHttpRoute,
+} from "@ekklesia/contracts";
+import type { Context, Hono } from "hono";
+import {
+  type AuthorizationMiddlewareOptions,
+  getAuthorizedPrincipal,
+  requirePermission,
+  requireTrustedOrigin,
+} from "./authorization-middleware.js";
+
+const MODULE_ROUTE_PREFIX = "/api/v1/modules";
+const STATE_CHANGING_METHODS: ReadonlySet<string> = new Set(["DELETE", "PATCH", "POST", "PUT"]);
+const STRIPPED_CORS_RESPONSE_HEADERS = [
+  "access-control-allow-credentials",
+  "access-control-allow-headers",
+  "access-control-allow-methods",
+  "access-control-allow-origin",
+  "access-control-expose-headers",
+  "access-control-max-age",
+];
+
+export interface ModuleHttpRoutesOptions extends AuthorizationMiddlewareOptions {
+  readonly trustedOrigins: ReadonlySet<string>;
+}
+
+/** Never carries the offending permission id, route path, module id, or any other configuration
+ * detail — a forged or inconsistent route snapshot is a startup-time composition bug, not
+ * something to describe in detail to whatever eventually logs it. */
+export class ModuleRouteConfigurationError extends Error {
+  constructor() {
+    super("A published module HTTP route references a permission that is not registered.");
+    this.name = "ModuleRouteConfigurationError";
+    this.stack = `${this.name}: ${this.message}`;
+    Object.freeze(this);
+  }
+}
+
+/** "/" is the module's own root and maps to the bare module prefix, never a required trailing
+ * slash; every other local path appends directly. Root and non-root therefore never collide, and
+ * `/api/v1/modules/<module-id>/` (the root path with a trailing slash) is never produced here. */
+function moduleRoutePath(moduleId: ModuleId, routePath: string): string {
+  return routePath === "/"
+    ? `${MODULE_ROUTE_PREFIX}/${moduleId}`
+    : `${MODULE_ROUTE_PREFIX}/${moduleId}${routePath}`;
+}
+
+function sanitizedModuleHandlerFailure(c: Context): Response {
+  c.header("Cache-Control", "no-store");
+  return c.json({ code: "MODULE_HANDLER_FAILED" }, 500);
+}
+
+/**
+ * The one shared `Vary` parsing/canonicalization primitive: splits and trims comma-separated
+ * tokens and de-duplicates them case-insensitively — `Vary` lists header *names*, which are
+ * themselves case-insensitive, so a module's own `origin` must collapse with a later `Origin`
+ * rather than appear as a separate, redundant entry — while preserving first-seen casing and
+ * relative order. Never returns early on `*`; callers decide what a `*` token means for their own
+ * policy (see `mergedVaryHeader` and `canonicalizeVaryHeader` below, the two callers that build on
+ * this instead of re-implementing parsing/dedup independently).
+ */
+function parseVaryTokens(existingVary: string | null): Map<string, string> {
+  const canonicalByLowercase = new Map<string, string>();
+  for (const token of (existingVary ?? "").split(",")) {
+    const trimmed = token.trim();
+    if (trimmed.length === 0) {
+      continue;
+    }
+    const key = trimmed.toLowerCase();
+    if (!canonicalByLowercase.has(key)) {
+      canonicalByLowercase.set(key, trimmed);
+    }
+  }
+  return canonicalByLowercase;
+}
+
+/** A literal `*` (RFC 9110 §12.5.5) must never be combined with any other value; since `*` already
+ * means "may vary on anything," a strictly broader signal than any explicit list, its presence
+ * collapses the result to `*` alone rather than producing an invalid combination. */
+function serializeVaryTokens(tokens: ReadonlyMap<string, string>): string {
+  if (tokens.has("*")) {
+    return "*";
+  }
+  return [...tokens.values()].join(", ");
+}
+
+/**
+ * Used only for a module's own response: always emits the canonical `Origin`/`Cookie` casing
+ * regardless of how (or whether) a module already listed them, since every module response is
+ * forced to vary on both (see `sanitizeModuleResponse`) — this is a deliberate product policy for
+ * module responses specifically, not a generic property every response through the platform's CORS
+ * boundary should have forced onto it (an `OPTIONS` preflight, for one, has no `Cookie` concept at
+ * all).
+ */
+export function mergedVaryHeader(existingVary: string | null): string {
+  const tokens = parseVaryTokens(existingVary);
+  if (tokens.has("*")) {
+    return "*";
+  }
+  tokens.set("origin", "Origin");
+  tokens.set("cookie", "Cookie");
+  return serializeVaryTokens(tokens);
+}
+
+/**
+ * Used at the app-level CORS boundary (`apps/api/src/app.ts`), which wraps every response —
+ * `OPTIONS` preflights and Core's own routes included, not only module ones — after Hono's own
+ * `cors()` has already appended its own `Vary: Origin`. Unlike `mergedVaryHeader`, this never
+ * injects a token that was not already present; it only de-duplicates and collapses `*`, since a
+ * generic boundary must not assume every response wants `Origin`/`Cookie` forced onto it.
+ */
+export function canonicalizeVaryHeader(existingVary: string): string {
+  return serializeVaryTokens(parseVaryTokens(existingVary));
+}
+
+/**
+ * The platform owns CORS and caching for every module route: strips any CORS-control header a
+ * handler set (defense in depth — the outer `cors()` middleware already computes the authoritative
+ * values for the actual response) and forces `Cache-Control: no-store` plus a `Vary` that always
+ * includes `Origin` and `Cookie`, since even a public-baseline handler receives an authorized
+ * principal and may personalize its response. A separate cache-policy contract is future work;
+ * this is the conservative default until then. A module's own legitimate `Vary` values (if any)
+ * are preserved alongside the forced ones. Never reads or buffers `response.body` — it is passed
+ * through to the new `Response` unread, so a streaming body is neither consumed nor blocked here.
+ */
+function sanitizeModuleResponse(response: Response): Response {
+  const headers = new Headers(response.headers);
+  for (const headerName of STRIPPED_CORS_RESPONSE_HEADERS) {
+    headers.delete(headerName);
+  }
+  headers.set("Cache-Control", "no-store");
+  headers.set("Vary", mergedVaryHeader(headers.get("Vary")));
+  return new Response(response.body, {
+    headers,
+    status: response.status,
+    statusText: response.statusText,
+  });
+}
+
+/**
+ * Mounts `StartedModuleRuntime`'s published, immutable route snapshot into `app`, in publication
+ * order — never sorted or mutated, and never invoking a handler while mounting. Every route is
+ * protected by the exact same `requirePermission` middleware Core's own routes use, with
+ * `route.permission` as the only permission id ever consulted and its baseline coming exclusively
+ * from `options.registry`; a state-changing method (`POST`/`PUT`/`PATCH`/`DELETE`) additionally
+ * requires `requireTrustedOrigin` before authorization ever runs. `GET` inherits Hono's own
+ * implicit `HEAD` handling, which re-enters this exact same middleware chain and strips the
+ * response body afterward — there is no separate `HEAD` registration or permission path.
+ * `route.handler` is invoked only after authorization succeeds, with the raw Fetch `Request` and a
+ * frozen context — never a Hono `Context`, database, store, or configuration.
+ *
+ * Because the routes and registry both derive from the same discovered inventory
+ * (`prepareStartupModuleInventory`), every registered route permission should already be
+ * registered; this loop still checks that invariant explicitly and throws
+ * `ModuleRouteConfigurationError` before mounting anything further if it ever does not hold, so a
+ * forged or hand-built route snapshot fails app construction instead of silently mounting an
+ * unenforceable route. `requirePermission`'s own per-request registry lookup remains the live,
+ * defense-in-depth enforcement regardless.
+ */
+export function mountModuleHttpRoutes(
+  app: Hono,
+  routes: readonly RegisteredModuleHttpRoute[],
+  options: ModuleHttpRoutesOptions,
+): void {
+  const middlewareOptions: AuthorizationMiddlewareOptions = {
+    evaluator: options.evaluator,
+    registry: options.registry,
+    runtime: options.runtime,
+  };
+  const requireOrigin = requireTrustedOrigin(options.trustedOrigins);
+
+  for (const route of routes) {
+    if (!options.registry.has(route.permission)) {
+      throw new ModuleRouteConfigurationError();
+    }
+
+    const requireRoutePermission = requirePermission(middlewareOptions, route.permission);
+    const path = moduleRoutePath(route.moduleId, route.path);
+    const finalHandler = async (c: Context): Promise<Response> => {
+      const context: ModuleRouteHandlerContext = Object.freeze({
+        moduleId: route.moduleId,
+        params: Object.freeze({ ...c.req.param() }),
+        principal: getAuthorizedPrincipal(c),
+      });
+
+      let response: Response;
+      try {
+        response = await route.handler(c.req.raw, context);
+      } catch {
+        return sanitizedModuleHandlerFailure(c);
+      }
+      if (!(response instanceof Response)) {
+        return sanitizedModuleHandlerFailure(c);
+      }
+      return sanitizeModuleResponse(response);
+    };
+
+    // Hono's `on()` overloads resolve by literal call arity, not by the runtime length of a spread
+    // array — each branch below is therefore a distinct, fixed-arity call rather than one call
+    // spreading a variable-length handlers array.
+    if (STATE_CHANGING_METHODS.has(route.method)) {
+      app.on(route.method, path, requireOrigin, requireRoutePermission, finalHandler);
+    } else {
+      app.on(route.method, path, requireRoutePermission, finalHandler);
+    }
+  }
+}
@@ -54,7 +54,7 @@ async function readPackageVersion(packagePath: string): Promise<string> {
  return packageData.version;
 }

-export interface ComposeStartupPermissionRegistryOptions {
+export interface PrepareStartupModuleInventoryOptions {
  /** Test-only escape hatch: overrides the directory module discovery scans for installed
   * modules. Never set by the executable entry point — production always discovers the real
   * repository's `modules/` directory. Platform and Module SDK versions are always read from the
@@ -62,7 +62,8 @@ export interface ComposeStartupPermissionRegistryOptions {
  readonly modulesDirectoryOverride?: string;
  /** Test-only escape hatch: supplies an already-discovered module list directly, skipping the
   * filesystem discovery step entirely, while still running the real `composePlatformPermissionRegistry`
-   * on it. Exists because a genuine exact permission-id collision between two modules is
+   * on it — and, if startup progresses that far, driving module runtime startup with this exact
+   * list too. Exists because a genuine exact permission-id collision between two modules is
   * unreachable through real discovery: module ids are unique (discovery itself rejects a
   * duplicate) and every permission id is namespaced by its own module's id, so no two
   * really-discovered modules can ever contribute the same permission id. Proving
@@ -76,18 +77,35 @@ export interface ComposeStartupPermissionRegistryOptions {
  readonly discoveredModulesOverride?: readonly DiscoveredModule[];
 }

+export type ComposeStartupPermissionRegistryOptions = PrepareStartupModuleInventoryOptions;
+
+export interface StartupModuleInventory {
+  /** The exact discovered-module list — in discovery order — permission composition ran against.
+   * Production startup (`apps/api/src/server.ts`) passes this same list to
+   * `startDiscoveredModuleRuntime` rather than letting the module runtime rediscover modules a
+   * second time. */
+  readonly modules: readonly DiscoveredModule[];
+  readonly permissionRegistry: PermissionRegistry;
+}
+
 /**
- * Discovers every installed module's manifest and composes the one immutable platform permission
- * registry (Core's own declarations plus every module's) — the production source of truth
- * `apps/api` enforces every request against. Only manifests are read; no module server entrypoint
- * is imported or executed, and no module lifecycle hook runs. Read the platform and Module SDK
- * versions only when this function actually executes, never at import time.
+ * Discovers every installed module's manifest exactly once and composes the one immutable platform
+ * permission registry (Core's own declarations plus every module's) from that exact discovered
+ * list — the production source of truth `apps/api` enforces every request against, and the exact
+ * module inventory `startDiscoveredModuleRuntime` starts from. Only manifests are read here; no
+ * module server entrypoint is imported or executed, and no module lifecycle hook runs. Read the
+ * platform and Module SDK versions only when this function actually executes, never at import
+ * time.
 */
-export async function composeStartupPermissionRegistry(
-  options: ComposeStartupPermissionRegistryOptions = {},
-): Promise<PermissionRegistry> {
+export async function prepareStartupModuleInventory(
+  options: PrepareStartupModuleInventoryOptions = {},
+): Promise<StartupModuleInventory> {
  if (options.discoveredModulesOverride) {
-    return composePlatformPermissionRegistry(options.discoveredModulesOverride);
+    const modules = options.discoveredModulesOverride;
+    return Object.freeze({
+      modules,
+      permissionRegistry: composePlatformPermissionRegistry(modules),
+    });
  }

  const repositoryRoot = resolveRepositoryRoot();
@@ -102,5 +120,24 @@ export async function composeStartupPermissionRegistry(
    platformVersion,
  });

-  return composePlatformPermissionRegistry(modules);
+  return Object.freeze({
+    modules,
+    permissionRegistry: composePlatformPermissionRegistry(modules),
+  });
+}
+
+/**
+ * Compatible wrapper for callers — currently only existing tests — that need this package's
+ * composed registry without the discovered module list itself. (Doctor and `modules:validate` are
+ * Core-owned and never call into `apps/api` at all; they call Core's own
+ * `composePlatformPermissionRegistry` directly over their own already-discovered module list.)
+ * Production `startApi` does not call this wrapper: it calls `prepareStartupModuleInventory`
+ * directly so it can hand the exact same discovered list to `startDiscoveredModuleRuntime`, rather
+ * than discarding it here and rediscovering modules a second time for runtime startup.
+ */
+export async function composeStartupPermissionRegistry(
+  options: ComposeStartupPermissionRegistryOptions = {},
+): Promise<PermissionRegistry> {
+  const inventory = await prepareStartupModuleInventory(options);
+  return inventory.permissionRegistry;
 }
@@ -5,13 +5,17 @@ import {
  createAuthorizationStore,
 } from "@ekklesia/core/authorization";
 import { createIdentityRuntime, type IdentityRateLimitOverride } from "@ekklesia/core/identity";
-import type { DiscoveredModule } from "@ekklesia/core/modules";
+import {
+  type DiscoveredModule,
+  type StartedModuleRuntime,
+  startDiscoveredModuleRuntime,
+} from "@ekklesia/core/modules";
 import { serve, type ServerType } from "@hono/node-server";
 import type { Hono } from "hono";
 import { createApiApp } from "./app.js";
 import { type ApiRuntimeConfig, createApiRuntimeConfig } from "./config.js";
 import { type ApiDatabaseHandle, createApiDatabase } from "./database.js";
-import { composeStartupPermissionRegistry } from "./platform-permissions.js";
+import { prepareStartupModuleInventory } from "./platform-permissions.js";

 const connectionTimeoutMs = 10_000;
 const operationTimeoutMs = 10_000;
@@ -26,12 +30,13 @@ export interface StartApiOptions {
  /** Test-only escape hatch: never set by the executable entry point. See
   * `IdentityRateLimitOverride` for why production must leave this unset. */
  readonly rateLimitOverride?: IdentityRateLimitOverride;
-  /** Test-only escape hatch: overrides the directory permission-composition module discovery
-   * scans. Never set by the executable entry point. See `composeStartupPermissionRegistry`. */
+  /** Test-only escape hatch: overrides the directory module discovery scans. Never set by the
+   * executable entry point. See `prepareStartupModuleInventory`. */
  readonly modulesDirectoryOverride?: string;
-  /** Test-only escape hatch: supplies an already-discovered module list directly to permission
-   * composition, skipping filesystem discovery entirely. Never set by the executable entry
-   * point. See `composeStartupPermissionRegistry`. */
+  /** Test-only escape hatch: supplies an already-discovered module list directly, skipping
+   * filesystem discovery entirely — this exact list drives both permission composition and module
+   * runtime startup. Never set by the executable entry point. See
+   * `prepareStartupModuleInventory`. */
  readonly discoveredModulesOverride?: readonly DiscoveredModule[];
 }

@@ -44,6 +49,17 @@ async function safeCloseDatabase(handle: ApiDatabaseHandle): Promise<void> {
  }
 }

+/** Same swallow-on-cleanup-path rule as `safeCloseDatabase`, used only while unwinding a startup
+ * failure that already occurred after the module runtime started — never during normal shutdown,
+ * where a module stop failure remains an observable result instead (see `startApi`'s `shutdown`). */
+async function safeStopModuleRuntime(moduleRuntime: StartedModuleRuntime): Promise<void> {
+  try {
+    await moduleRuntime.stop();
+  } catch {
+    // See safeCloseDatabase: never mask the startup failure already propagating.
+  }
+}
+
 function bindServer(app: Hono, host: string, port: number): Promise<ServerType> {
  return new Promise((resolve, reject) => {
    let settled = false;
@@ -63,25 +79,36 @@ function bindServer(app: Hono, host: string, port: number): Promise<ServerType>
 }

 /**
- * Explicit runtime composition, in a fixed order: discover every installed module's manifest and
- * compose the one immutable platform permission registry from Core's own declarations plus every
- * module's (`./platform-permissions.js`); only then construct the one shared PostgreSQL pool
- * (identity and authorization each get a typed Drizzle view over it — see `./database.js`), the
- * Core identity runtime, the Core authorization store and evaluator, and the Hono application;
- * finally start the Node HTTP server. Permission composition happens before any pool, Better
- * Auth instance, or HTTP server exists, so a discovery or composition failure — an invalid
+ * Explicit runtime composition, in a fixed order:
+ *
+ * 1. Discover every installed module's manifest exactly once and compose the one immutable
+ *    platform permission registry from Core's own declarations plus every module's
+ *    (`prepareStartupModuleInventory`, `./platform-permissions.js`).
+ * 2. Construct the one shared PostgreSQL pool (identity and authorization each get a typed
+ *    Drizzle view over it — see `./database.js`).
+ * 3. Construct the Core identity runtime, authorization store, and evaluator.
+ * 4. Start the module runtime from that exact same discovered inventory
+ *    (`startDiscoveredModuleRuntime`) — never rediscovering modules a second time.
+ * 5. Create the Hono application, mounting the started module runtime's published routes.
+ * 6. Bind the Node HTTP server.
+ *
+ * Discovery and permission composition happen before any pool, Better Auth instance, module
+ * entrypoint import, or HTTP server exists, so a discovery or composition failure — an invalid
 * manifest, a dependency-graph problem, a module claiming the reserved `core.*` permission
 * namespace, or a duplicate permission declaration — leaves nothing to close: it propagates
- * directly, and startup never falls back to a Core-only registry. Returns a handle with an
- * idempotent `shutdown()` so both the executable entry point and tests can stop the server and
- * close the shared pool deterministically. Never applies migrations or generates schema — the
- * database must already be migrated through `pnpm migrations:apply`.
+ * directly, and startup never falls back to a Core-only registry. Core infrastructure (the pool,
+ * identity, authorization) exists before any executable module lifecycle code runs, and every
+ * module route is published only after the entire module runtime has registered and started
+ * successfully, so no request can ever reach a module before every module has started. Returns a
+ * handle with an idempotent `shutdown()` so both the executable entry point and tests can stop the
+ * server, the module runtime, and the shared pool deterministically. Never applies migrations or
+ * generates schema — the database must already be migrated through `pnpm migrations:apply`.
 */
 export async function startApi(
  config: ApiRuntimeConfig,
  options: StartApiOptions = {},
 ): Promise<RunningApi> {
-  const permissionRegistry = await composeStartupPermissionRegistry({
+  const inventory = await prepareStartupModuleInventory({
    ...(options.modulesDirectoryOverride === undefined
      ? {}
      : { modulesDirectoryOverride: options.modulesDirectoryOverride }),
@@ -114,16 +141,40 @@ export async function startApi(
    platformOwners: authorizationStore,
  });

-  const app = createApiApp({
-    authorization: { evaluator, registry: permissionRegistry, store: authorizationStore },
-    runtime,
-    trustedOrigins: config.identity.trustedOrigins,
-  });
+  // Module load/register/start failures use Core's own existing rollback (already-started
+  // modules are stopped, in reverse order, before this rejects) — there is no separate runtime
+  // handle to stop here, only the pool this failure leaves open.
+  let moduleRuntime: StartedModuleRuntime;
+  try {
+    moduleRuntime = await startDiscoveredModuleRuntime(inventory.modules);
+  } catch (error) {
+    await safeCloseDatabase(databaseHandle);
+    throw error;
+  }
+
+  let app: Hono;
+  try {
+    app = createApiApp({
+      authorization: {
+        evaluator,
+        registry: inventory.permissionRegistry,
+        store: authorizationStore,
+      },
+      moduleRoutes: moduleRuntime.routes,
+      runtime,
+      trustedOrigins: config.identity.trustedOrigins,
+    });
+  } catch (error) {
+    await safeStopModuleRuntime(moduleRuntime);
+    await safeCloseDatabase(databaseHandle);
+    throw error;
+  }

  let server: ServerType;
  try {
    server = await bindServer(app, config.host, config.port);
  } catch (error) {
+    await safeStopModuleRuntime(moduleRuntime);
    await safeCloseDatabase(databaseHandle);
    throw error;
  }
@@ -133,7 +184,12 @@ export async function startApi(
  // would previously get an already-resolved `undefined` immediately, before the listener had
  // actually drained or the pool had actually closed. Storing the promise itself means every
  // caller — concurrent or sequential — awaits the exact same drain-then-close operation and
-  // observes it complete (or fail) exactly once.
+  // observes it complete (or fail) exactly once. Order matters: the HTTP listener is drained and
+  // closed first so no new or in-flight request can reach a module handler while the module
+  // runtime is stopping, then the module runtime stops, then the shared pool closes. Unlike the
+  // startup-cleanup paths above, a module-stop failure here is not swallowed — it is a genuine
+  // shutdown result a caller should observe — but database cleanup still always runs first, so a
+  // stop failure never leaves the pool open.
  let shutdownPromise: Promise<void> | undefined;
  const shutdown = (): Promise<void> => {
    if (!shutdownPromise) {
@@ -141,7 +197,16 @@ export async function startApi(
        await new Promise<void>((resolve) => {
          server.close(() => resolve());
        });
+        let moduleStopError: unknown;
+        try {
+          await moduleRuntime.stop();
+        } catch (error) {
+          moduleStopError = error;
+        }
        await safeCloseDatabase(databaseHandle);
+        if (moduleStopError) {
+          throw moduleStopError;
+        }
      })();
    }
    return shutdownPromise;
@@ -200,6 +200,7 @@ async function applyCoreMigrations(url: string): Promise<void> {
 }

 const trackedModulesDirectories: string[] = [];
+const eventSymbols: symbol[] = [];

 async function createFixtureModulesDirectory(): Promise<string> {
  const directory = await mkdtemp(path.join(tmpdir(), "ekklesia-api-installed-modules-"));
@@ -207,13 +208,31 @@ async function createFixtureModulesDirectory(): Promise<string> {
  return directory;
 }

-/** Writes a minimal, structurally valid module fixture straight to disk — real discovery and
- * composition run against it, nothing hand-built. The server entrypoint throws immediately if
- * ever imported/executed, so a scenario that completes without that throw firing is direct
- * evidence permission composition and Doctor never ran module lifecycle code. */
+/** A dynamically imported module fixture cannot close over this test file's local variables, so
+ * lifecycle markers cross that boundary through a `globalThis` symbol instead (same technique as
+ * `core/tests/module-runtime.test.ts`). */
+function createEventRecorder(): { events: string[]; expression: string } {
+  const key = `ekklesia.api.integration.test.${eventSymbols.length}.${Date.now()}.${Math.random()}`;
+  const symbol = Symbol.for(key);
+  const events: string[] = [];
+  (globalThis as unknown as Record<PropertyKey, unknown>)[symbol] = events;
+  eventSymbols.push(symbol);
+  return { events, expression: `globalThis[Symbol.for(${JSON.stringify(key)})]` };
+}
+
+/** Writes a minimal, structurally valid module fixture straight to disk — real discovery,
+ * composition, and (where a scenario actually starts the API) real module runtime execution all
+ * run against it, nothing hand-built. Register/start/stop push markers onto `recorder.events`
+ * instead of throwing, so both "Doctor/composition never executed this" (an empty recorder) and
+ * "startApi actually imported, registered, and started this" (a populated recorder) can be proven
+ * against the exact same fixture. When declared with the `calendar.events.read` permission, the
+ * module also registers a restricted `GET /events/:eventId` route and a restricted, state-changing
+ * `POST /events` route against that same permission, so the full HTTP mounting/enforcement chain
+ * can be exercised live. */
 async function createFixtureModule(
  modulesDirectory: string,
  id: string,
+  recorder: { expression: string },
  manifestOverrides: Record<string, unknown> = {},
 ): Promise<void> {
  const moduleDirectory = path.join(modulesDirectory, id);
@@ -227,6 +246,9 @@ async function createFixtureModule(
    entrypoints: { server: "./dist/server/index.js" },
    ...manifestOverrides,
  };
+  const declaresCalendarRead = (manifest.permissions as ReadonlyArray<{ id: string }>).some(
+    (declaration) => declaration.id === "calendar.events.read",
+  );
  await mkdir(path.join(moduleDirectory, "dist/server"), { recursive: true });
  await Promise.all([
    writeFile(
@@ -241,7 +263,39 @@ async function createFixtureModule(
    writeFile(path.join(moduleDirectory, "ekklesia.module.json"), JSON.stringify(manifest)),
    writeFile(
      path.join(moduleDirectory, "dist/server/index.js"),
-      'throw new Error("permission composition and Doctor must never execute a module server entrypoint");',
+      `export default {
+        id: ${JSON.stringify(id)},
+        version: "0.1.0",
+        register({ http }) {
+          ${recorder.expression}.push(${JSON.stringify(`${id}:register`)});
+          ${
+            declaresCalendarRead
+              ? `http.route({
+                  method: "GET",
+                  path: "/events/:eventId",
+                  permission: "calendar.events.read",
+                  async handler(request, context) {
+                    return Response.json({ eventId: context.params.eventId, principal: context.principal });
+                  },
+                });
+                http.route({
+                  method: "POST",
+                  path: "/events",
+                  permission: "calendar.events.read",
+                  async handler(request, context) {
+                    return Response.json({ created: true, principal: context.principal }, { status: 201 });
+                  },
+                });`
+              : ""
+          }
+        },
+        start() {
+          ${recorder.expression}.push(${JSON.stringify(`${id}:start`)});
+        },
+        stop() {
+          ${recorder.expression}.push(${JSON.stringify(`${id}:stop`)});
+        },
+      };`,
    ),
  ]);
 }
@@ -253,6 +307,10 @@ afterAll(async () => {
  for (const directory of trackedModulesDirectories.splice(0)) {
    await rm(directory, { recursive: true, force: true }).catch(() => undefined);
  }
+  const globalValues = globalThis as unknown as Record<PropertyKey, unknown>;
+  for (const symbol of eventSymbols.splice(0)) {
+    delete globalValues[symbol];
+  }
 });

 const identityBaseUrl = "https://identity.example.test";
@@ -1222,10 +1280,11 @@ describe.sequential("live API — installed module permission end-to-end", () =>
  const password = "correct horse battery staple";
  const modulePermission = "calendar.events.read";
  const absentPermission = "scheduler.jobs.read";
+  const recorder = createEventRecorder();

  it("recognizes a real installed module and passes permission composition in Doctor, without executing its server entrypoint", async () => {
    modulesDirectory = await createFixtureModulesDirectory();
-    await createFixtureModule(modulesDirectory, "calendar", {
+    await createFixtureModule(modulesDirectory, "calendar", recorder, {
      permissions: [
        {
          baseline: "restricted",
@@ -1257,14 +1316,21 @@ describe.sequential("live API — installed module permission end-to-end", () =>
      details: ["2 permissions registered"],
      status: "pass",
    });
+    // Doctor and permission composition read only the manifest — the fixture's register/start
+    // markers must remain entirely unset.
+    expect(recorder.events).toEqual([]);
  });

-  it("starts a freshly migrated API that discovers the fixture module and signs up its eventual owner", async () => {
+  it("starts a freshly migrated API that discovers the fixture module, imports and starts its runtime exactly once, and mounts its route", async () => {
    database = await createDisposableDatabase("authz_module");
    await applyCoreMigrations(database.url);
    running = await startMigratedApi(database.url, modulesDirectory);
    origin = apiOrigin(running);

+    // Unlike Doctor above, a successful production startup does deliberately import, register,
+    // and start the module's runtime — exactly once each.
+    expect(recorder.events).toEqual(["calendar:register", "calendar:start"]);
+
    const ownerSignUp = await signUp(origin, ownerEmail, password);
    ownerUserId = ownerSignUp.body.user.id;
    const ownerSignIn = await signIn(origin, ownerEmail, password);
@@ -1316,6 +1382,56 @@ describe.sequential("live API — installed module permission end-to-end", () =>
    }
  });

+  it("denies the module's own mounted route to an anonymous caller, then serves it to the newly granted owner with the decoded path parameter and authenticated principal", async () => {
+    const anonymousResponse = await fetch(`${origin}/api/v1/modules/calendar/events/evt-42`);
+    expect(anonymousResponse.status).toBe(403);
+    expect(await anonymousResponse.json()).toEqual({ code: "AUTHORIZATION_DENIED" });
+
+    const grantedResponse = await fetch(`${origin}/api/v1/modules/calendar/events/evt-42`, {
+      headers: { cookie: ownerCookie },
+    });
+    expect(grantedResponse.status).toBe(200);
+    const body = (await grantedResponse.json()) as {
+      eventId: string;
+      principal: { kind: string; userId: string };
+    };
+    expect(body.eventId).toBe("evt-42");
+    expect(body.principal).toEqual({ kind: "authenticated", userId: ownerUserId });
+  });
+
+  it("requires a trusted Origin for the module's own state-changing route, exactly like the platform's own mutation routes", async () => {
+    const noOriginResponse = await fetch(`${origin}/api/v1/modules/calendar/events`, {
+      body: JSON.stringify({}),
+      headers: { "content-type": "application/json", cookie: ownerCookie },
+      method: "POST",
+    });
+    expect(noOriginResponse.status).toBe(403);
+    expect(await noOriginResponse.json()).toEqual({ code: "UNTRUSTED_ORIGIN" });
+
+    const untrustedResponse = await fetch(`${origin}/api/v1/modules/calendar/events`, {
+      body: JSON.stringify({}),
+      headers: {
+        "content-type": "application/json",
+        cookie: ownerCookie,
+        origin: untrustedOrigin,
+      },
+      method: "POST",
+    });
+    expect(untrustedResponse.status).toBe(403);
+
+    const trustedResponse = await fetch(`${origin}/api/v1/modules/calendar/events`, {
+      body: JSON.stringify({}),
+      headers: {
+        "content-type": "application/json",
+        cookie: ownerCookie,
+        origin: dashboardOrigin,
+      },
+      method: "POST",
+    });
+    expect(trustedResponse.status).toBe(201);
+    expect(await trustedResponse.json()).toMatchObject({ created: true });
+  });
+
  it("rejects a well-formed permission absent from the composed registry, writing no grant or audit row", async () => {
    const admin = await openAdministrativeClient(database.url);
    try {
@@ -1355,15 +1471,24 @@ describe.sequential("live API — installed module permission end-to-end", () =>
    }
  });

-  it("shuts down cleanly, then restarting with the module absent rejects new grants for its former permission while the historical grant remains listable", async () => {
+  it("shuts down cleanly, then restarting with the module absent rejects new grants for its former permission, returns NOT_FOUND for its former route, while the historical grant remains listable", async () => {
    await running.shutdown();
    const remainingConnections = await activeConnectionCount(database.name);
    expect(remainingConnections).toBe(0);
+    // Exactly one stop, matching the exactly-one register/start already asserted above.
+    expect(recorder.events.filter((event) => event === "calendar:stop")).toHaveLength(1);

    const emptyModulesDirectory = await createFixtureModulesDirectory();
    running = await startMigratedApi(database.url, emptyModulesDirectory);
    origin = apiOrigin(running);

+    // The module's own route is unmounted along with the module itself.
+    const removedRouteResponse = await fetch(`${origin}/api/v1/modules/calendar/events/evt-42`, {
+      headers: { cookie: ownerCookie },
+    });
+    expect(removedRouteResponse.status).toBe(404);
+    expect(await removedRouteResponse.json()).toEqual({ code: "NOT_FOUND" });
+
    // The owner's existing session survives the restart (sessions live in the database, not the
    // process), so the same cookie proves ordinary identity behavior is unaffected here too.
    const listResponse = await fetch(`${origin}/api/v1/grants?userId=${ownerUserId}`, {
@@ -52,6 +52,7 @@ describe("Ekklesia API Hono application", () => {
  it("mounts Better Auth exactly under /api/auth/*", async () => {
    const runtime = fakeRuntime();
    const app = createApiApp({
+      moduleRoutes: Object.freeze([]),
      authorization: fakeAuthorization({}),
      runtime,
      trustedOrigins: [trustedOrigin],
@@ -67,6 +68,7 @@ describe("Ekklesia API Hono application", () => {
  it("does not route requests outside /api/auth/* to Better Auth", async () => {
    const runtime = fakeRuntime();
    const app = createApiApp({
+      moduleRoutes: Object.freeze([]),
      authorization: fakeAuthorization({}),
      runtime,
      trustedOrigins: [trustedOrigin],
@@ -83,6 +85,7 @@ describe("Ekklesia API Hono application", () => {
      resolvePrincipal: vi.fn().mockResolvedValue(ANONYMOUS_PRINCIPAL),
    });
    const app = createApiApp({
+      moduleRoutes: Object.freeze([]),
      authorization: fakeAuthorization({}),
      runtime,
      trustedOrigins: [trustedOrigin],
@@ -96,11 +99,33 @@ describe("Ekklesia API Hono application", () => {
    expect(response.headers.get("vary")).toContain("Cookie");
  });

+  it("never duplicates Origin in Vary even though the route sets it directly and Hono's own CORS middleware also appends it", async () => {
+    const runtime = fakeRuntime({
+      resolvePrincipal: vi.fn().mockResolvedValue(ANONYMOUS_PRINCIPAL),
+    });
+    const app = createApiApp({
+      moduleRoutes: Object.freeze([]),
+      authorization: fakeAuthorization({}),
+      runtime,
+      trustedOrigins: [trustedOrigin],
+    });
+
+    const response = await app.request("/api/v1/principal", {
+      headers: { origin: trustedOrigin },
+    });
+
+    const vary = response.headers.get("vary") ?? "";
+    const tokens = vary.split(",").map((token) => token.trim().toLowerCase());
+    expect(tokens.filter((token) => token === "origin")).toHaveLength(1);
+    expect(tokens).toContain("cookie");
+  });
+
  it("returns the authenticated principal shape containing only kind and userId", async () => {
    const runtime = fakeRuntime({
      resolvePrincipal: vi.fn().mockResolvedValue(createAuthenticatedPrincipal("user_123")),
    });
    const app = createApiApp({
+      moduleRoutes: Object.freeze([]),
      authorization: fakeAuthorization({}),
      runtime,
      trustedOrigins: [trustedOrigin],
@@ -121,6 +146,7 @@ describe("Ekklesia API Hono application", () => {
        .mockRejectedValue(new IdentityRuntimeError("PRINCIPAL_RESOLUTION_FAILED")),
    });
    const app = createApiApp({
+      moduleRoutes: Object.freeze([]),
      authorization: fakeAuthorization({}),
      runtime,
      trustedOrigins: [trustedOrigin],
@@ -138,6 +164,7 @@ describe("Ekklesia API Hono application", () => {
      handleAuthRequest: vi.fn().mockRejectedValue(new Error("postgresql://admin:secret@db/x")),
    });
    const app = createApiApp({
+      moduleRoutes: Object.freeze([]),
      authorization: fakeAuthorization({}),
      runtime,
      trustedOrigins: [trustedOrigin],
@@ -154,6 +181,7 @@ describe("Ekklesia API Hono application", () => {

  it("has deterministic 404 behavior for an unknown route", async () => {
    const app = createApiApp({
+      moduleRoutes: Object.freeze([]),
      authorization: fakeAuthorization({}),
      runtime: fakeRuntime(),
      trustedOrigins: [trustedOrigin],
@@ -167,6 +195,7 @@ describe("Ekklesia API Hono application", () => {

  it("reflects an allowed origin in Access-Control-Allow-Origin with credentials support", async () => {
    const app = createApiApp({
+      moduleRoutes: Object.freeze([]),
      authorization: fakeAuthorization({}),
      runtime: fakeRuntime(),
      trustedOrigins: [trustedOrigin],
@@ -182,6 +211,7 @@ describe("Ekklesia API Hono application", () => {

  it("never returns Access-Control-Allow-Origin for a disallowed origin", async () => {
    const app = createApiApp({
+      moduleRoutes: Object.freeze([]),
      authorization: fakeAuthorization({}),
      runtime: fakeRuntime(),
      trustedOrigins: [trustedOrigin],
@@ -196,6 +226,7 @@ describe("Ekklesia API Hono application", () => {

  it("supports requests with no Origin header at all (native/server clients)", async () => {
    const app = createApiApp({
+      moduleRoutes: Object.freeze([]),
      authorization: fakeAuthorization({}),
      runtime: fakeRuntime(),
      trustedOrigins: [trustedOrigin],
@@ -208,6 +239,7 @@ describe("Ekklesia API Hono application", () => {

  it("handles preflight OPTIONS requests deterministically for an allowed origin", async () => {
    const app = createApiApp({
+      moduleRoutes: Object.freeze([]),
      authorization: fakeAuthorization({}),
      runtime: fakeRuntime(),
      trustedOrigins: [trustedOrigin],
@@ -227,6 +259,7 @@ describe("Ekklesia API Hono application", () => {

  it("never wildcards Access-Control-Allow-Origin", async () => {
    const app = createApiApp({
+      moduleRoutes: Object.freeze([]),
      authorization: fakeAuthorization({}),
      runtime: fakeRuntime(),
      trustedOrigins: [trustedOrigin],
@@ -249,6 +282,7 @@ describe("Ekklesia API Hono application", () => {
    it("mounts the v1 grants routes under /api/v1/grants", async () => {
      const evaluatorAuthorize = vi.fn().mockResolvedValue({ allowed: false });
      const app = createApiApp({
+        moduleRoutes: Object.freeze([]),
        authorization: fakeAuthorization({ evaluator: { authorize: evaluatorAuthorize } }),
        runtime: fakeRuntime(),
        trustedOrigins: [trustedOrigin],
@@ -274,6 +308,7 @@ describe("Ekklesia API Hono application", () => {
        has: () => false,
      };
      const app = createApiApp({
+        moduleRoutes: Object.freeze([]),
        authorization: fakeAuthorization({
          evaluator: { authorize: evaluatorAuthorize },
          registry: emptyRegistry,
@@ -290,6 +325,7 @@ describe("Ekklesia API Hono application", () => {

    it("applies the same CORS policy to /api/v1/grants as the rest of /api/v1/*", async () => {
      const app = createApiApp({
+        moduleRoutes: Object.freeze([]),
        authorization: fakeAuthorization({}),
        runtime: fakeRuntime(),
        trustedOrigins: [trustedOrigin],
@@ -13,6 +13,13 @@ vi.mock("pg", () => ({ Pool: poolConstructor }));
 vi.mock("better-auth", () => ({ betterAuth: betterAuthMock }));
 vi.mock("better-auth/adapters/drizzle", () => ({ drizzleAdapter: drizzleAdapterMock }));
 vi.mock("@hono/node-server", () => ({ serve: serveMock }));
+// Wraps the real `createApiApp` in a spy rather than replacing it, so every existing test still
+// gets the real Hono application; only the one test that deliberately forces an app-construction
+// failure overrides this with `mockImplementationOnce`.
+vi.mock("../src/app.js", async (importOriginal) => {
+  const actual = await importOriginal<typeof import("../src/app.js")>();
+  return { ...actual, createApiApp: vi.fn(actual.createApiApp) };
+});

 import { parseModuleManifest } from "@ekklesia/contracts";
 import {
@@ -21,6 +28,7 @@ import {
  ModulePermissionCompositionError,
 } from "@ekklesia/core/modules";
 import { PermissionRegistryError } from "@ekklesia/core/authorization";
+import { createApiApp } from "../src/app.js";
 import { createApiRuntimeConfig } from "../src/config.js";
 import { installShutdownSignalHandlers, startApi } from "../src/server.js";

@@ -87,6 +95,76 @@ async function createFixtureModule(
  ]);
 }

+const eventSymbols: symbol[] = [];
+
+/** Same technique as `core/tests/module-runtime.test.ts`: a dynamically imported module fixture
+ * cannot close over this test file's local variables, so lifecycle events cross that boundary
+ * through a `globalThis` symbol instead. Returns the same `events` array the fixture's generated
+ * source pushes into, so test code can both read it directly and push its own markers (pool
+ * close, server close) onto the identical array to observe cross-cutting shutdown order. */
+function createEventRecorder(): { events: string[]; expression: string } {
+  const key = `ekklesia.api.lifecycle.test.${eventSymbols.length}.${Date.now()}.${Math.random()}`;
+  const symbol = Symbol.for(key);
+  const events: string[] = [];
+  (globalThis as unknown as Record<PropertyKey, unknown>)[symbol] = events;
+  eventSymbols.push(symbol);
+  return { events, expression: `globalThis[Symbol.for(${JSON.stringify(key)})]` };
+}
+
+interface WorkingFixtureModuleOptions {
+  /** Declares one `GET /ping` route against `<id>.ping.read` when true. */
+  readonly withRoute?: boolean;
+  readonly registerThrows?: boolean;
+  readonly startThrows?: boolean;
+  readonly stopThrows?: boolean;
+  readonly dependencies?: Record<string, unknown>;
+}
+
+/** Writes a real, working module fixture — unlike `createFixtureModule`, this entrypoint does not
+ * throw on import; it pushes lifecycle markers onto `recorder.events` and can be told to fail at a
+ * specific hook, so tests can prove exactly what a successful (or a specifically-failing) module
+ * runtime startup actually executes and in what order, relative to pool/server construction. */
+async function createWorkingFixtureModule(
+  modulesDirectory: string,
+  id: string,
+  recorder: { expression: string },
+  options: WorkingFixtureModuleOptions = {},
+): Promise<void> {
+  const permissionId = `${id}.ping.read`;
+  await createFixtureModule(modulesDirectory, id, {
+    permissions: options.withRoute
+      ? [{ baseline: "public", description: "Ping.", id: permissionId }]
+      : [],
+    ...(options.dependencies ? { dependencies: options.dependencies } : {}),
+  });
+  const routeSource = options.withRoute
+    ? `http.route({
+        method: "GET",
+        path: "/ping",
+        permission: ${JSON.stringify(permissionId)},
+        handler: async () => new Response("pong", { status: 200 }),
+      });`
+    : "";
+  const serverSource = `export default {
+    id: ${JSON.stringify(id)},
+    version: "0.1.0",
+    register({ http }) {
+      ${recorder.expression}.push(${JSON.stringify(`${id}:register`)});
+      ${routeSource}
+      ${options.registerThrows ? 'throw new Error("register failed");' : ""}
+    },
+    start() {
+      ${recorder.expression}.push(${JSON.stringify(`${id}:start`)});
+      ${options.startThrows ? 'throw new Error("start failed");' : ""}
+    },
+    stop() {
+      ${recorder.expression}.push(${JSON.stringify(`${id}:stop`)});
+      ${options.stopThrows ? 'throw new Error("stop failed");' : ""}
+    },
+  };`;
+  await writeFile(path.join(modulesDirectory, id, "dist/server/index.js"), serverSource);
+}
+
 /** A minimal, in-memory `DiscoveredModule` double built from a real, validated manifest — used
 * only to reach `composePlatformPermissionRegistry`'s own duplicate-detection failure, which is
 * unreachable through real filesystem discovery (module ids are unique and every permission id is
@@ -518,3 +596,252 @@ describe("Ekklesia API module permission composition at startup", () => {
    expect(poolConstructor).not.toHaveBeenCalled();
  });
 });
+
+describe("Ekklesia API module runtime startup and shutdown", () => {
+  afterEach(async () => {
+    const globalValues = globalThis as unknown as Record<PropertyKey, unknown>;
+    for (const symbol of eventSymbols.splice(0)) {
+      delete globalValues[symbol];
+    }
+    await Promise.all(
+      temporaryDirectories.splice(0).map((directory) => rm(directory, { recursive: true })),
+    );
+  });
+
+  beforeEach(() => {
+    poolConstructor.mockReset();
+    betterAuthMock.mockReset();
+    drizzleAdapterMock.mockClear();
+    serveMock.mockReset();
+    vi.mocked(createApiApp).mockClear();
+  });
+
+  function mockPoolAndAuth(): { poolEnd: ReturnType<typeof vi.fn> } {
+    const poolEnd = vi.fn().mockResolvedValue(undefined);
+    poolConstructor.mockImplementation(function fakePool() {
+      return { end: poolEnd, on: vi.fn() };
+    });
+    betterAuthMock.mockReturnValue({ api: { getSession: vi.fn() }, handler: vi.fn() });
+    return { poolEnd };
+  }
+
+  it("starts the module runtime from the exact discovered inventory permission composition used, mounting routes in discovery order", async () => {
+    const modulesDirectory = await createTemporaryModulesDirectory();
+    const recorder = createEventRecorder();
+    await createWorkingFixtureModule(modulesDirectory, "alpha", recorder, { withRoute: true });
+    await createWorkingFixtureModule(modulesDirectory, "beta", recorder, { withRoute: true });
+    mockPoolAndAuth();
+    mockSuccessfulServe();
+
+    const running = await startApi(validConfig(), { modulesDirectoryOverride: modulesDirectory });
+
+    expect(recorder.events).toEqual([
+      "alpha:register",
+      "beta:register",
+      "alpha:start",
+      "beta:start",
+    ]);
+    // Hono records one internal route entry per handler in a route's middleware chain, not one
+    // per logical route, so entries for the same method/path are deduplicated (preserving first-
+    // seen order) before asserting mounting order.
+    const moduleRoutePaths = [
+      ...new Set(
+        running.app.routes
+          .filter((route) => route.path.startsWith("/api/v1/modules/"))
+          .map((route) => `${route.method} ${route.path}`),
+      ),
+    ];
+    expect(moduleRoutePaths).toEqual([
+      "GET /api/v1/modules/alpha/ping",
+      "GET /api/v1/modules/beta/ping",
+    ]);
+
+    await running.shutdown();
+  });
+
+  it("closes the pool exactly once and binds no server when a module's entrypoint fails to load", async () => {
+    const modulesDirectory = await createTemporaryModulesDirectory();
+    await createFixtureModule(modulesDirectory, "broken-export");
+    await writeFile(
+      path.join(modulesDirectory, "broken-export", "dist/server/index.js"),
+      "export default { thisIsNotAValidRuntimeDefinition: true };",
+    );
+    const { poolEnd } = mockPoolAndAuth();
+
+    await expect(
+      startApi(validConfig(), { modulesDirectoryOverride: modulesDirectory }),
+    ).rejects.toMatchObject({
+      issues: [expect.objectContaining({ code: "MODULE_RUNTIME_EXPORT_INVALID" })],
+    });
+
+    expect(poolConstructor).toHaveBeenCalledTimes(1);
+    expect(poolEnd).toHaveBeenCalledTimes(1);
+    expect(serveMock).not.toHaveBeenCalled();
+  });
+
+  it("closes the pool exactly once and binds no server when a module's register hook fails", async () => {
+    const modulesDirectory = await createTemporaryModulesDirectory();
+    const recorder = createEventRecorder();
+    await createWorkingFixtureModule(modulesDirectory, "register-fails", recorder, {
+      registerThrows: true,
+    });
+    const { poolEnd } = mockPoolAndAuth();
+
+    await expect(
+      startApi(validConfig(), { modulesDirectoryOverride: modulesDirectory }),
+    ).rejects.toMatchObject({
+      issues: [expect.objectContaining({ code: "MODULE_REGISTER_FAILED" })],
+    });
+
+    expect(recorder.events).toEqual(["register-fails:register"]);
+    expect(poolConstructor).toHaveBeenCalledTimes(1);
+    expect(poolEnd).toHaveBeenCalledTimes(1);
+    expect(serveMock).not.toHaveBeenCalled();
+  });
+
+  it("closes the pool exactly once and binds no server when a module's start hook fails, preserving Core's rollback of already-started modules", async () => {
+    const modulesDirectory = await createTemporaryModulesDirectory();
+    const recorder = createEventRecorder();
+    await createWorkingFixtureModule(modulesDirectory, "one", recorder);
+    await createWorkingFixtureModule(modulesDirectory, "two", recorder, {
+      dependencies: { modules: { required: { one: "^0.1.0" } } },
+      startThrows: true,
+    });
+    const { poolEnd } = mockPoolAndAuth();
+
+    await expect(
+      startApi(validConfig(), { modulesDirectoryOverride: modulesDirectory }),
+    ).rejects.toMatchObject({
+      issues: [expect.objectContaining({ code: "MODULE_START_FAILED" })],
+    });
+
+    expect(recorder.events).toEqual([
+      "one:register",
+      "two:register",
+      "one:start",
+      "two:start",
+      "one:stop",
+    ]);
+    expect(poolConstructor).toHaveBeenCalledTimes(1);
+    expect(poolEnd).toHaveBeenCalledTimes(1);
+    expect(serveMock).not.toHaveBeenCalled();
+  });
+
+  it("stops the module runtime and closes the pool, binding no server, when app construction fails", async () => {
+    const modulesDirectory = await createTemporaryModulesDirectory();
+    const recorder = createEventRecorder();
+    await createWorkingFixtureModule(modulesDirectory, "mounted", recorder);
+    const { poolEnd } = mockPoolAndAuth();
+    vi.mocked(createApiApp).mockImplementationOnce(() => {
+      throw new Error("forced app construction failure");
+    });
+
+    await expect(
+      startApi(validConfig(), { modulesDirectoryOverride: modulesDirectory }),
+    ).rejects.toThrow("forced app construction failure");
+
+    expect(recorder.events).toEqual(["mounted:register", "mounted:start", "mounted:stop"]);
+    expect(poolConstructor).toHaveBeenCalledTimes(1);
+    expect(poolEnd).toHaveBeenCalledTimes(1);
+    expect(serveMock).not.toHaveBeenCalled();
+  });
+
+  it("stops the module runtime and closes the pool when the server fails to bind", async () => {
+    const modulesDirectory = await createTemporaryModulesDirectory();
+    const recorder = createEventRecorder();
+    await createWorkingFixtureModule(modulesDirectory, "mounted", recorder);
+    const { poolEnd } = mockPoolAndAuth();
+    mockFailingServe(new Error("EADDRINUSE"));
+
+    await expect(
+      startApi(validConfig(), { modulesDirectoryOverride: modulesDirectory }),
+    ).rejects.toThrow();
+
+    expect(recorder.events).toEqual(["mounted:register", "mounted:start", "mounted:stop"]);
+    expect(poolConstructor).toHaveBeenCalledTimes(1);
+    expect(poolEnd).toHaveBeenCalledTimes(1);
+  });
+
+  it("drains the HTTP server, then stops the module runtime, then closes the pool, in that exact order", async () => {
+    const modulesDirectory = await createTemporaryModulesDirectory();
+    const recorder = createEventRecorder();
+    await createWorkingFixtureModule(modulesDirectory, "ordered", recorder);
+    poolConstructor.mockImplementation(function fakePool() {
+      return {
+        end: vi.fn(async () => {
+          recorder.events.push("pool:end");
+        }),
+        on: vi.fn(),
+      };
+    });
+    betterAuthMock.mockReturnValue({ api: { getSession: vi.fn() }, handler: vi.fn() });
+    const { server } = mockSuccessfulServe();
+    const originalClose = server.close;
+    server.close = vi.fn((callback?: () => void) => {
+      recorder.events.push("server:close");
+      return originalClose(callback);
+    });
+
+    const running = await startApi(validConfig(), { modulesDirectoryOverride: modulesDirectory });
+    recorder.events.length = 0;
+    await running.shutdown();
+
+    expect(recorder.events).toEqual(["server:close", "ordered:stop", "pool:end"]);
+  });
+
+  it("still runs pool cleanup and lets the shutdown rejection surface when the module runtime fails to stop", async () => {
+    const modulesDirectory = await createTemporaryModulesDirectory();
+    const recorder = createEventRecorder();
+    await createWorkingFixtureModule(modulesDirectory, "stop-fails", recorder, {
+      stopThrows: true,
+    });
+    const { poolEnd } = mockPoolAndAuth();
+    mockSuccessfulServe();
+
+    const running = await startApi(validConfig(), { modulesDirectoryOverride: modulesDirectory });
+
+    await expect(running.shutdown()).rejects.toMatchObject({
+      issues: [expect.objectContaining({ code: "MODULE_STOP_FAILED", moduleId: "stop-fails" })],
+    });
+    expect(poolEnd).toHaveBeenCalledTimes(1);
+  });
+
+  it("keeps a direct discoveredModulesOverride driving both permission composition and module runtime startup", async () => {
+    const modulesDirectory = await createTemporaryModulesDirectory();
+    const recorder = createEventRecorder();
+    await createWorkingFixtureModule(modulesDirectory, "calendar", recorder, { withRoute: true });
+    const discovered = await (await import("@ekklesia/core/modules")).discoverModules({
+      moduleSdkVersion: "0.1.0",
+      modulesDirectory,
+      platformVersion: "0.1.0",
+    });
+    mockPoolAndAuth();
+    mockSuccessfulServe();
+
+    const running = await startApi(validConfig(), { discoveredModulesOverride: discovered });
+
+    expect(recorder.events).toEqual(["calendar:register", "calendar:start"]);
+    // Hono records one internal route entry per handler in a route's middleware chain, not one
+    // per logical route, so entries for the same method/path are deduplicated (preserving first-
+    // seen order) before asserting mounting order.
+    const moduleRoutePaths = [
+      ...new Set(
+        running.app.routes
+          .filter((route) => route.path.startsWith("/api/v1/modules/"))
+          .map((route) => `${route.method} ${route.path}`),
+      ),
+    ];
+    expect(moduleRoutePaths).toEqual(["GET /api/v1/modules/calendar/ping"]);
+
+    await running.shutdown();
+  });
+
+  it("performs no filesystem I/O, module import, pool construction, Better Auth construction, or server binding merely by importing the module-route adapter", async () => {
+    const module = await import("../src/module-http-routes.js");
+
+    expect(typeof module.mountModuleHttpRoutes).toBe("function");
+    expect(poolConstructor).not.toHaveBeenCalled();
+    expect(betterAuthMock).not.toHaveBeenCalled();
+    expect(serveMock).not.toHaveBeenCalled();
+  });
+});
@@ -4,12 +4,17 @@ import {
  type CapabilityRegistrar,
  type CapabilityResolver,
  capabilityIdSchema,
+  type ModuleHttpRouteRegistrar,
  type ModuleId,
  type ModuleRegistrationContext,
+  type ModuleRouteDefinitionInput,
  type ModuleRuntimeContext,
  type ModuleRuntimeDefinition,
+  moduleRouteShapeKey,
  parseModuleRuntimeDefinition,
  type RegisteredCapability,
+  type RegisteredModuleHttpRoute,
+  safeParseModuleRouteDefinition,
 } from "@ekklesia/contracts";
 import {
  type DiscoveredModule,
@@ -27,6 +32,12 @@ export type ModuleRuntimeIssueCode =
  | "MODULE_CAPABILITY_UNREGISTERED"
  | "MODULE_REGISTER_FAILED"
  | "MODULE_ROLLBACK_FAILED"
+  | "MODULE_ROUTE_DEFINITION_INVALID"
+  | "MODULE_ROUTE_DUPLICATE"
+  | "MODULE_ROUTE_METHOD_INVALID"
+  | "MODULE_ROUTE_PATH_INVALID"
+  | "MODULE_ROUTE_PERMISSION_INVALID"
+  | "MODULE_ROUTE_PERMISSION_UNDECLARED"
  | "MODULE_RUNTIME_EXPORT_INVALID"
  | "MODULE_RUNTIME_ID_MISMATCH"
  | "MODULE_RUNTIME_IMPORT_FAILED"
@@ -53,6 +64,9 @@ export interface RunningModule {
 export interface StartedModuleRuntime {
  readonly capabilities: CapabilityRegistry;
  readonly modules: readonly RunningModule[];
+  /** One immutable startup snapshot: discovered-module order, then registration order within each
+   * module. Never mutated after startup — there is no dynamic route addition or removal. */
+  readonly routes: readonly RegisteredModuleHttpRoute[];
  stop(): Promise<void>;
 }

@@ -63,11 +77,16 @@ interface LoadedModule {
  readonly discovered: DiscoveredModule;
 }

-interface RegistrationStage {
-  readonly context: ModuleRegistrationContext;
+interface CapabilityRegistrationStage {
+  readonly capabilities: CapabilityRegistrar;
  commit(): readonly ModuleRuntimeIssue[];
 }

+interface HttpRouteRegistrationStage {
+  readonly http: ModuleHttpRouteRegistrar;
+  commit(): void;
+}
+
 class ModuleRuntimeSignal extends Error {
  readonly issue: ModuleRuntimeIssue;

@@ -109,7 +128,7 @@ function defaultExport(moduleNamespace: unknown): unknown {
 class StagedCapabilityRegistry {
  readonly #registered = new Map<CapabilityId, RegisteredCapability>();

-  createRegistrationStage(module: DiscoveredModule): RegistrationStage {
+  createRegistrationStage(module: DiscoveredModule): CapabilityRegistrationStage {
    const local = new Map<CapabilityId, RegisteredCapability>();
    const declarations = new Map(
      module.manifest.capabilities.map((declaration) => [declaration.id, declaration] as const),
@@ -154,13 +173,9 @@ class StagedCapabilityRegistry {
      },
      resolve,
    });
-    const context: ModuleRegistrationContext = Object.freeze({
-      capabilities,
-      moduleId: module.manifest.id,
-    });

    return {
-      context,
+      capabilities,
      commit: (): readonly ModuleRuntimeIssue[] => {
        const missing = [...declarations.keys()]
          .filter((capabilityId) => !local.has(capabilityId))
@@ -252,6 +267,88 @@ class StagedCapabilityRegistry {
  }
 }

+/**
+ * Stages a module's HTTP route registrations during `register`, exactly like
+ * `StagedCapabilityRegistry` stages capability provision: routes accumulate in a per-module local
+ * list, validated and rejected immediately (`ModuleRuntimeSignal`) at the `http.route(...)` call
+ * site, and are only merged into the shared, eventually-published list by `commit()` — called only
+ * after the module's `register` hook returns without throwing. Unlike capabilities, there is no
+ * "declared but never provided" concept for routes (a manifest never declares routes), so `commit`
+ * has nothing to validate; it only publishes what already passed validation.
+ */
+class StagedModuleHttpRoutes {
+  readonly #routes: RegisteredModuleHttpRoute[] = [];
+
+  createRegistrationStage(module: DiscoveredModule): HttpRouteRegistrationStage {
+    const local: RegisteredModuleHttpRoute[] = [];
+    const shapes = new Set<string>();
+    const ownedPermissionIds = new Set(
+      module.manifest.permissions.map((declaration) => declaration.id),
+    );
+
+    const http: ModuleHttpRouteRegistrar = Object.freeze({
+      route: (definition: ModuleRouteDefinitionInput): void => {
+        const parsed = safeParseModuleRouteDefinition(definition);
+        if (!parsed.success) {
+          throw new ModuleRuntimeSignal(
+            runtimeIssue(
+              parsed.code,
+              "register",
+              module.manifest.id,
+              `Module ${module.manifest.id} registered an invalid HTTP route.`,
+            ),
+          );
+        }
+        // Ownership is checked against this module's own manifest-declared permissions only, never
+        // the composed platform registry — a module can therefore never gate a route with Core's or
+        // another module's permission, structurally, regardless of what that other permission is.
+        if (!ownedPermissionIds.has(parsed.data.permission)) {
+          throw new ModuleRuntimeSignal(
+            runtimeIssue(
+              "MODULE_ROUTE_PERMISSION_UNDECLARED",
+              "register",
+              module.manifest.id,
+              `Module ${module.manifest.id} registered an HTTP route with a permission its own manifest does not declare.`,
+            ),
+          );
+        }
+        const shapeKey = moduleRouteShapeKey(parsed.data.method, parsed.data.path);
+        if (shapes.has(shapeKey)) {
+          throw new ModuleRuntimeSignal(
+            runtimeIssue(
+              "MODULE_ROUTE_DUPLICATE",
+              "register",
+              module.manifest.id,
+              `Module ${module.manifest.id} registered a duplicate HTTP route.`,
+            ),
+          );
+        }
+        shapes.add(shapeKey);
+        local.push(
+          Object.freeze({
+            handler: parsed.data.handler,
+            method: parsed.data.method,
+            moduleId: module.manifest.id,
+            path: parsed.data.path,
+            permission: parsed.data.permission,
+          }),
+        );
+      },
+    });
+
+    return {
+      http,
+      commit: (): void => {
+        this.#routes.push(...local);
+      },
+    };
+  }
+
+  publish(): readonly RegisteredModuleHttpRoute[] {
+    return Object.freeze([...this.#routes]);
+  }
+}
+
 async function loadRuntimeDefinitions(
  discoveredModules: readonly DiscoveredModule[],
 ): Promise<readonly LoadedModule[]> {
@@ -327,12 +424,19 @@ async function loadRuntimeDefinitions(

 async function registerModules(
  modules: readonly LoadedModule[],
-  registry: StagedCapabilityRegistry,
+  capabilityRegistry: StagedCapabilityRegistry,
+  httpRoutes: StagedModuleHttpRoutes,
 ): Promise<void> {
  for (const module of modules) {
-    const stage = registry.createRegistrationStage(module.discovered);
+    const capabilityStage = capabilityRegistry.createRegistrationStage(module.discovered);
+    const routeStage = httpRoutes.createRegistrationStage(module.discovered);
+    const context: ModuleRegistrationContext = Object.freeze({
+      capabilities: capabilityStage.capabilities,
+      http: routeStage.http,
+      moduleId: module.discovered.manifest.id,
+    });
    try {
-      await module.definition.register?.(stage.context);
+      await module.definition.register?.(context);
    } catch (error) {
      if (error instanceof ModuleRuntimeSignal) {
        throw new ModuleRuntimeError([error.issue]);
@@ -346,10 +450,15 @@ async function registerModules(
        ),
      ]);
    }
-    const issues = stage.commit();
+    const issues = capabilityStage.commit();
    if (issues.length > 0) {
      throw new ModuleRuntimeError(issues);
    }
+    // Routes are only merged into the shared published list once this module's registration has
+    // fully succeeded (register hook did not throw, and every declared capability was provided) —
+    // a failed registration therefore publishes no routes for this module, matching the same
+    // all-or-nothing guarantee capabilities already have.
+    routeStage.commit();
  }
 }

@@ -405,16 +514,25 @@ async function startModules(
  }
 }

-export async function startModuleRuntime(
-  options: StartModuleRuntimeOptions,
+/**
+ * Starts the module runtime from a module list the caller already discovered — performs no
+ * module-directory scan or manifest read of its own, and preserves the given list's order exactly.
+ * `startModuleRuntime` below is the convenient discovery-plus-start wrapper most callers want;
+ * `apps/api`'s production startup calls this form directly (`prepareStartupModuleInventory`,
+ * `apps/api/src/platform-permissions.ts`) so permission composition and module HTTP/runtime
+ * startup share the exact same one-time discovery rather than discovering modules twice.
+ */
+export async function startDiscoveredModuleRuntime(
+  discoveredModules: readonly DiscoveredModule[],
 ): Promise<StartedModuleRuntime> {
-  const discovered = await discoverModules(options);
-  const modules = await loadRuntimeDefinitions(discovered);
-  const stagedRegistry = new StagedCapabilityRegistry();
-  await registerModules(modules, stagedRegistry);
-  await startModules(modules, stagedRegistry);
+  const modules = await loadRuntimeDefinitions(discoveredModules);
+  const capabilityRegistry = new StagedCapabilityRegistry();
+  const httpRoutes = new StagedModuleHttpRoutes();
+  await registerModules(modules, capabilityRegistry, httpRoutes);
+  await startModules(modules, capabilityRegistry);

-  const capabilities = stagedRegistry.publish();
+  const capabilities = capabilityRegistry.publish();
+  const routes = httpRoutes.publish();
  const runningModules = Object.freeze(
    modules.map((module) =>
      Object.freeze({
@@ -428,9 +546,10 @@ export async function startModuleRuntime(
  return Object.freeze({
    capabilities,
    modules: runningModules,
+    routes,
    stop: (): Promise<void> => {
      stopPromise ??= (async () => {
-        const issues = await stopModules(modules, stagedRegistry, "stop");
+        const issues = await stopModules(modules, capabilityRegistry, "stop");
        if (issues.length > 0) {
          throw new ModuleRuntimeError(issues);
        }
@@ -439,3 +558,10 @@ export async function startModuleRuntime(
    },
  });
 }
+
+export async function startModuleRuntime(
+  options: StartModuleRuntimeOptions,
+): Promise<StartedModuleRuntime> {
+  const discovered = await discoverModules(options);
+  return startDiscoveredModuleRuntime(discovered);
+}
@@ -0,0 +1,26 @@
+import { describe, expect, it, vi } from "vitest";
+
+const readdir = vi.fn();
+const readFile = vi.fn();
+const realpath = vi.fn();
+const stat = vi.fn();
+
+vi.mock("node:fs/promises", async (importOriginal) => ({
+  ...(await importOriginal<typeof import("node:fs/promises")>()),
+  readdir,
+  readFile,
+  realpath,
+  stat,
+}));
+
+describe("module HTTP contract and runtime import safety", () => {
+  it("performs no filesystem I/O merely by importing the module runtime or the module-http contract", async () => {
+    await import("../src/modules/index.js");
+    await import("@ekklesia/contracts");
+
+    expect(readdir).not.toHaveBeenCalled();
+    expect(readFile).not.toHaveBeenCalled();
+    expect(realpath).not.toHaveBeenCalled();
+    expect(stat).not.toHaveBeenCalled();
+  });
+});
@@ -1,14 +1,21 @@
 import { mkdir, mkdtemp, rm, writeFile } from "node:fs/promises";
 import { tmpdir } from "node:os";
 import path from "node:path";
-import { afterEach, describe, expect, it } from "vitest";
+import { afterEach, describe, expect, it, vi } from "vitest";
+import { discoverModules } from "../src/modules/discovery.js";
 import {
  ModuleDiscoveryError,
  ModuleRuntimeError,
  type ModuleRuntimeIssueCode,
+  startDiscoveredModuleRuntime,
  startModuleRuntime,
 } from "../src/modules/index.js";

+vi.mock("../src/modules/discovery.js", async (importOriginal) => {
+  const actual = await importOriginal<typeof import("../src/modules/discovery.js")>();
+  return { ...actual, discoverModules: vi.fn(actual.discoverModules) };
+});
+
 interface RuntimeModuleFixture {
  readonly directory?: string;
  readonly manifest?: Record<string, unknown>;
@@ -40,6 +47,7 @@ function manifestFor(
  options: {
    capabilities?: Array<{ id: string; version: string }>;
    dependencies?: Record<string, unknown>;
+    permissions?: Array<{ id: string; baseline: string; description: string }>;
  } = {},
 ): Record<string, unknown> {
  return {
@@ -52,7 +60,7 @@ function manifestFor(
      moduleSdk: "^0.1.0",
    },
    capabilities: options.capabilities ?? [],
-    permissions: [],
+    permissions: options.permissions ?? [],
    ...(options.dependencies ? { dependencies: options.dependencies } : {}),
    entrypoints: {
      server: "./dist/server/index.js",
@@ -370,3 +378,482 @@ describe("module runtime", () => {
    expect(JSON.stringify(error.issues)).not.toContain(modulesDirectory);
  });
 });
+
+function noopHandlerSource(): string {
+  return "() => new Response(null, { status: 204 })";
+}
+
+function permissionDeclaration(
+  id: string,
+  baseline: "authenticated" | "public" | "restricted" = "restricted",
+): { id: string; baseline: string; description: string } {
+  return { id, baseline, description: `Test permission ${id}.` };
+}
+
+describe("module HTTP routes", () => {
+  it("registers one route and publishes it on the started runtime", async () => {
+    const modulesDirectory = await createModulesDirectory();
+    await createRuntimeModule(modulesDirectory, "single", {
+      manifest: manifestFor("single", {
+        permissions: [permissionDeclaration("single.items.read")],
+      }),
+      serverSource: `export default {
+        id: "single", version: "0.1.0",
+        register({ http }) {
+          http.route({
+            method: "GET",
+            path: "/items",
+            permission: "single.items.read",
+            handler: ${noopHandlerSource()},
+          });
+        }
+      };`,
+    });
+
+    const runtime = await startModuleRuntime(runtimeOptions(modulesDirectory));
+    expect(runtime.routes).toHaveLength(1);
+    expect(runtime.routes[0]).toMatchObject({
+      moduleId: "single",
+      method: "GET",
+      path: "/items",
+      permission: "single.items.read",
+    });
+    await runtime.stop();
+  });
+
+  it("retains registration order within a module and discovery order across modules", async () => {
+    const modulesDirectory = await createModulesDirectory();
+    await createRuntimeModule(modulesDirectory, "alpha", {
+      manifest: manifestFor("alpha", {
+        permissions: [
+          permissionDeclaration("alpha.first.read"),
+          permissionDeclaration("alpha.second.read"),
+        ],
+      }),
+      serverSource: `export default {
+        id: "alpha", version: "0.1.0",
+        register({ http }) {
+          http.route({ method: "GET", path: "/first", permission: "alpha.first.read", handler: ${noopHandlerSource()} });
+          http.route({ method: "GET", path: "/second", permission: "alpha.second.read", handler: ${noopHandlerSource()} });
+        }
+      };`,
+    });
+    await createRuntimeModule(modulesDirectory, "beta", {
+      manifest: manifestFor("beta", {
+        permissions: [permissionDeclaration("beta.third.read")],
+      }),
+      serverSource: `export default {
+        id: "beta", version: "0.1.0",
+        register({ http }) {
+          http.route({ method: "GET", path: "/third", permission: "beta.third.read", handler: ${noopHandlerSource()} });
+        }
+      };`,
+    });
+
+    const runtime = await startModuleRuntime(runtimeOptions(modulesDirectory));
+    expect(
+      runtime.routes.map((route) => `${route.moduleId}:${route.method}:${route.path}`),
+    ).toEqual(["alpha:GET:/first", "alpha:GET:/second", "beta:GET:/third"]);
+    await runtime.stop();
+  });
+
+  it("allows the same path under different methods", async () => {
+    const modulesDirectory = await createModulesDirectory();
+    await createRuntimeModule(modulesDirectory, "same-path", {
+      manifest: manifestFor("same-path", {
+        permissions: [
+          permissionDeclaration("same-path.items.read"),
+          permissionDeclaration("same-path.items.write"),
+        ],
+      }),
+      serverSource: `export default {
+        id: "same-path", version: "0.1.0",
+        register({ http }) {
+          http.route({ method: "GET", path: "/items", permission: "same-path.items.read", handler: ${noopHandlerSource()} });
+          http.route({ method: "POST", path: "/items", permission: "same-path.items.write", handler: ${noopHandlerSource()} });
+        }
+      };`,
+    });
+
+    const runtime = await startModuleRuntime(runtimeOptions(modulesDirectory));
+    expect(runtime.routes.map((route) => `${route.method} ${route.path}`)).toEqual([
+      "GET /items",
+      "POST /items",
+    ]);
+    await runtime.stop();
+  });
+
+  it("rejects a duplicate method/path route registered by the same module", async () => {
+    const modulesDirectory = await createModulesDirectory();
+    await createRuntimeModule(modulesDirectory, "dup", {
+      manifest: manifestFor("dup", {
+        permissions: [permissionDeclaration("dup.items.read")],
+      }),
+      serverSource: `export default {
+        id: "dup", version: "0.1.0",
+        register({ http }) {
+          http.route({ method: "GET", path: "/items", permission: "dup.items.read", handler: ${noopHandlerSource()} });
+          http.route({ method: "GET", path: "/items", permission: "dup.items.read", handler: ${noopHandlerSource()} });
+        }
+      };`,
+    });
+
+    const error = await captureRuntimeError(modulesDirectory);
+    expect(runtimeIssueCodes(error)).toEqual(["MODULE_ROUTE_DUPLICATE"]);
+  });
+
+  it("collides parameter-name-only path variants under the same method", async () => {
+    const modulesDirectory = await createModulesDirectory();
+    await createRuntimeModule(modulesDirectory, "param-shape", {
+      manifest: manifestFor("param-shape", {
+        permissions: [permissionDeclaration("param-shape.events.read")],
+      }),
+      serverSource: `export default {
+        id: "param-shape", version: "0.1.0",
+        register({ http }) {
+          http.route({ method: "GET", path: "/events/:eventId", permission: "param-shape.events.read", handler: ${noopHandlerSource()} });
+          http.route({ method: "GET", path: "/events/:id", permission: "param-shape.events.read", handler: ${noopHandlerSource()} });
+        }
+      };`,
+    });
+
+    const error = await captureRuntimeError(modulesDirectory);
+    expect(runtimeIssueCodes(error)).toEqual(["MODULE_ROUTE_DUPLICATE"]);
+  });
+
+  it("fails a malformed route with its specific structured issue code", async () => {
+    const badMethodDirectory = await createModulesDirectory();
+    await createRuntimeModule(badMethodDirectory, "bad-method", {
+      manifest: manifestFor("bad-method", {
+        permissions: [permissionDeclaration("bad-method.items.read")],
+      }),
+      serverSource: `export default {
+        id: "bad-method", version: "0.1.0",
+        register({ http }) {
+          http.route({ method: "get", path: "/items", permission: "bad-method.items.read", handler: ${noopHandlerSource()} });
+        }
+      };`,
+    });
+    expect(runtimeIssueCodes(await captureRuntimeError(badMethodDirectory))).toEqual([
+      "MODULE_ROUTE_METHOD_INVALID",
+    ]);
+
+    const badPathDirectory = await createModulesDirectory();
+    await createRuntimeModule(badPathDirectory, "bad-path", {
+      manifest: manifestFor("bad-path", {
+        permissions: [permissionDeclaration("bad-path.items.read")],
+      }),
+      serverSource: `export default {
+        id: "bad-path", version: "0.1.0",
+        register({ http }) {
+          http.route({ method: "GET", path: "items", permission: "bad-path.items.read", handler: ${noopHandlerSource()} });
+        }
+      };`,
+    });
+    expect(runtimeIssueCodes(await captureRuntimeError(badPathDirectory))).toEqual([
+      "MODULE_ROUTE_PATH_INVALID",
+    ]);
+
+    const badDefinitionDirectory = await createModulesDirectory();
+    await createRuntimeModule(badDefinitionDirectory, "bad-shape", {
+      manifest: manifestFor("bad-shape", {
+        permissions: [permissionDeclaration("bad-shape.items.read")],
+      }),
+      serverSource: `export default {
+        id: "bad-shape", version: "0.1.0",
+        register({ http }) {
+          http.route({
+            method: "GET",
+            path: "/items",
+            permission: "bad-shape.items.read",
+            baseline: "public",
+            handler: ${noopHandlerSource()},
+          });
+        }
+      };`,
+    });
+    expect(runtimeIssueCodes(await captureRuntimeError(badDefinitionDirectory))).toEqual([
+      "MODULE_ROUTE_DEFINITION_INVALID",
+    ]);
+  });
+
+  it("rejects a route permission the registering module does not itself declare", async () => {
+    const modulesDirectory = await createModulesDirectory();
+    await createRuntimeModule(modulesDirectory, "undeclared", {
+      manifest: manifestFor("undeclared"),
+      serverSource: `export default {
+        id: "undeclared", version: "0.1.0",
+        register({ http }) {
+          http.route({ method: "GET", path: "/items", permission: "undeclared.items.read", handler: ${noopHandlerSource()} });
+        }
+      };`,
+    });
+
+    const error = await captureRuntimeError(modulesDirectory);
+    expect(runtimeIssueCodes(error)).toEqual(["MODULE_ROUTE_PERMISSION_UNDECLARED"]);
+  });
+
+  it("rejects a module gating a route with a Core-owned permission it cannot declare", async () => {
+    const modulesDirectory = await createModulesDirectory();
+    await createRuntimeModule(modulesDirectory, "coreattempt", {
+      manifest: manifestFor("coreattempt"),
+      serverSource: `export default {
+        id: "coreattempt", version: "0.1.0",
+        register({ http }) {
+          http.route({
+            method: "GET",
+            path: "/items",
+            permission: "core.authorization.grants.manage",
+            handler: ${noopHandlerSource()},
+          });
+        }
+      };`,
+    });
+
+    const error = await captureRuntimeError(modulesDirectory);
+    expect(runtimeIssueCodes(error)).toEqual(["MODULE_ROUTE_PERMISSION_UNDECLARED"]);
+  });
+
+  it("rejects a module gating a route with another module's permission", async () => {
+    const modulesDirectory = await createModulesDirectory();
+    await createRuntimeModule(modulesDirectory, "alpha", {
+      manifest: manifestFor("alpha", {
+        permissions: [permissionDeclaration("alpha.items.read")],
+      }),
+      serverSource: `export default { id: "alpha", version: "0.1.0" };`,
+    });
+    await createRuntimeModule(modulesDirectory, "beta", {
+      manifest: manifestFor("beta"),
+      serverSource: `export default {
+        id: "beta", version: "0.1.0",
+        register({ http }) {
+          http.route({ method: "GET", path: "/items", permission: "alpha.items.read", handler: ${noopHandlerSource()} });
+        }
+      };`,
+    });
+
+    const error = await captureRuntimeError(modulesDirectory);
+    expect(runtimeIssueCodes(error)).toEqual(["MODULE_ROUTE_PERMISSION_UNDECLARED"]);
+  });
+
+  it("accepts a declared public, authenticated, or restricted permission without interpreting its baseline", async () => {
+    const modulesDirectory = await createModulesDirectory();
+    await createRuntimeModule(modulesDirectory, "baselines", {
+      manifest: manifestFor("baselines", {
+        permissions: [
+          permissionDeclaration("baselines.public.read", "public"),
+          permissionDeclaration("baselines.authenticated.read", "authenticated"),
+          permissionDeclaration("baselines.restricted.read", "restricted"),
+        ],
+      }),
+      serverSource: `export default {
+        id: "baselines", version: "0.1.0",
+        register({ http }) {
+          http.route({ method: "GET", path: "/public", permission: "baselines.public.read", handler: ${noopHandlerSource()} });
+          http.route({ method: "GET", path: "/authenticated", permission: "baselines.authenticated.read", handler: ${noopHandlerSource()} });
+          http.route({ method: "GET", path: "/restricted", permission: "baselines.restricted.read", handler: ${noopHandlerSource()} });
+        }
+      };`,
+    });
+
+    const runtime = await startModuleRuntime(runtimeOptions(modulesDirectory));
+    expect(runtime.routes).toHaveLength(3);
+    for (const route of runtime.routes) {
+      expect(Object.keys(route).sort()).toEqual([
+        "handler",
+        "method",
+        "moduleId",
+        "path",
+        "permission",
+      ]);
+    }
+    await runtime.stop();
+  });
+
+  it("never invokes a route handler while registering or starting", async () => {
+    const modulesDirectory = await createModulesDirectory();
+    const recorder = createEventRecorder();
+    await createRuntimeModule(modulesDirectory, "never-invoked", {
+      manifest: manifestFor("never-invoked", {
+        permissions: [permissionDeclaration("never-invoked.items.read")],
+      }),
+      serverSource: `export default {
+        id: "never-invoked", version: "0.1.0",
+        register({ http }) {
+          http.route({
+            method: "GET",
+            path: "/items",
+            permission: "never-invoked.items.read",
+            handler: () => { ${recorder.expression}.push("handler:called"); return new Response(null, { status: 204 }); },
+          });
+        }
+      };`,
+    });
+
+    const runtime = await startModuleRuntime(runtimeOptions(modulesDirectory));
+    expect(recorder.events).toEqual([]);
+    await runtime.stop();
+    expect(recorder.events).toEqual([]);
+  });
+
+  it("publishes frozen, immutable routes as a frozen route list", async () => {
+    const modulesDirectory = await createModulesDirectory();
+    await createRuntimeModule(modulesDirectory, "frozen", {
+      manifest: manifestFor("frozen", {
+        permissions: [permissionDeclaration("frozen.items.read")],
+      }),
+      serverSource: `export default {
+        id: "frozen", version: "0.1.0",
+        register({ http }) {
+          http.route({ method: "GET", path: "/items", permission: "frozen.items.read", handler: ${noopHandlerSource()} });
+        }
+      };`,
+    });
+
+    const runtime = await startModuleRuntime(runtimeOptions(modulesDirectory));
+    expect(Object.isFrozen(runtime.routes)).toBe(true);
+    expect(Object.isFrozen(runtime.routes[0])).toBe(true);
+    await runtime.stop();
+  });
+
+  it("does not let a module mutate the published route by mutating its own definition afterward", async () => {
+    const modulesDirectory = await createModulesDirectory();
+    await createRuntimeModule(modulesDirectory, "mutate", {
+      manifest: manifestFor("mutate", {
+        permissions: [
+          permissionDeclaration("mutate.items.read"),
+          permissionDeclaration("mutate.other.read"),
+        ],
+      }),
+      serverSource: `export default {
+        id: "mutate", version: "0.1.0",
+        register({ http }) {
+          const definition = {
+            method: "GET",
+            path: "/items",
+            permission: "mutate.items.read",
+            handler: ${noopHandlerSource()},
+          };
+          http.route(definition);
+          definition.method = "POST";
+          definition.path = "/mutated";
+          definition.permission = "mutate.other.read";
+        }
+      };`,
+    });
+
+    const runtime = await startModuleRuntime(runtimeOptions(modulesDirectory));
+    expect(runtime.routes[0]).toMatchObject({
+      method: "GET",
+      path: "/items",
+      permission: "mutate.items.read",
+    });
+    await runtime.stop();
+  });
+
+  it("publishes no runtime when a later module's route registration fails", async () => {
+    const modulesDirectory = await createModulesDirectory();
+    await createRuntimeModule(modulesDirectory, "first-ok", {
+      manifest: manifestFor("first-ok", {
+        permissions: [permissionDeclaration("first-ok.items.read")],
+      }),
+      serverSource: `export default {
+        id: "first-ok", version: "0.1.0",
+        register({ http }) {
+          http.route({ method: "GET", path: "/items", permission: "first-ok.items.read", handler: ${noopHandlerSource()} });
+        }
+      };`,
+    });
+    await createRuntimeModule(modulesDirectory, "second-bad", {
+      manifest: manifestFor("second-bad"),
+      serverSource: `export default {
+        id: "second-bad", version: "0.1.0",
+        register({ http }) {
+          http.route({ method: "GET", path: "/items", permission: "second-bad.items.read", handler: ${noopHandlerSource()} });
+        }
+      };`,
+    });
+
+    const error = await captureRuntimeError(modulesDirectory);
+    expect(runtimeIssueCodes(error)).toEqual(["MODULE_ROUTE_PERMISSION_UNDECLARED"]);
+    expect(error.issues[0]?.moduleId).toBe("second-bad");
+  });
+
+  it("preserves existing rollback behavior when a registered route's module later fails to start", async () => {
+    const modulesDirectory = await createModulesDirectory();
+    const recorder = createEventRecorder();
+    await createRuntimeModule(modulesDirectory, "routed", {
+      manifest: manifestFor("routed", {
+        permissions: [permissionDeclaration("routed.items.read")],
+      }),
+      serverSource: `export default {
+        id: "routed", version: "0.1.0",
+        register({ http }) {
+          http.route({ method: "GET", path: "/items", permission: "routed.items.read", handler: ${noopHandlerSource()} });
+        },
+        start() { ${recorder.expression}.push("routed:start"); },
+        stop() { ${recorder.expression}.push("routed:stop"); }
+      };`,
+    });
+    await createRuntimeModule(modulesDirectory, "failing", {
+      manifest: manifestFor("failing", {
+        dependencies: { modules: { required: { routed: "^0.1.0" } } },
+      }),
+      serverSource: `export default {
+        id: "failing", version: "0.1.0",
+        start() { throw new Error("boom"); }
+      };`,
+    });
+
+    const error = await captureRuntimeError(modulesDirectory);
+    expect(runtimeIssueCodes(error)).toEqual(["MODULE_START_FAILED"]);
+    expect(recorder.events).toEqual(["routed:start", "routed:stop"]);
+  });
+});
+
+describe("already-discovered module runtime", () => {
+  it("starts from an already-discovered inventory without a second directory scan", async () => {
+    const modulesDirectory = await createModulesDirectory();
+    await createRuntimeModule(modulesDirectory, "already-discovered", {
+      serverSource: `export default { id: "already-discovered", version: "0.1.0" };`,
+    });
+
+    vi.mocked(discoverModules).mockClear();
+    const discovered = await discoverModules(runtimeOptions(modulesDirectory));
+    expect(discoverModules).toHaveBeenCalledTimes(1);
+
+    const runtime = await startDiscoveredModuleRuntime(discovered);
+    expect(discoverModules).toHaveBeenCalledTimes(1);
+    expect(runtime.modules.map((module) => module.id)).toEqual(["already-discovered"]);
+    await runtime.stop();
+  });
+
+  it("preserves the given discovered-module list order exactly, without re-sorting", async () => {
+    const modulesDirectory = await createModulesDirectory();
+    await createRuntimeModule(modulesDirectory, "first", {
+      serverSource: `export default { id: "first", version: "0.1.0" };`,
+    });
+    await createRuntimeModule(modulesDirectory, "second", {
+      serverSource: `export default { id: "second", version: "0.1.0" };`,
+    });
+
+    const discovered = await discoverModules(runtimeOptions(modulesDirectory));
+    expect(discovered.map((module) => module.manifest.id)).toEqual(["first", "second"]);
+
+    const runtime = await startDiscoveredModuleRuntime([...discovered].reverse());
+    expect(runtime.modules.map((module) => module.id)).toEqual(["second", "first"]);
+    await runtime.stop();
+  });
+
+  it("startModuleRuntime remains backward-compatible and discovers exactly once", async () => {
+    const modulesDirectory = await createModulesDirectory();
+    await createRuntimeModule(modulesDirectory, "compat", {
+      serverSource: `export default { id: "compat", version: "0.1.0" };`,
+    });
+
+    vi.mocked(discoverModules).mockClear();
+    const runtime = await startModuleRuntime(runtimeOptions(modulesDirectory));
+    expect(discoverModules).toHaveBeenCalledTimes(1);
+    await runtime.stop();
+  });
+});
@@ -28,6 +28,15 @@ registry, which conflicts with install-by-cloning discovery.
 > ordering — remains accepted and unchanged. This section is left as originally accepted, as the
 > historical record of the manifest's prior shape.

+> **Cross-reference — see [ADR 0015](0015-static-module-http-routing-and-runtime-lifecycle.md).**
+> "HTTP routing... remain[s] outside this slice" (Consequences, below) and "The injected contexts
+> contain only the module ID and a capability registrar or resolver" (this section, below) described
+> this ADR's own scope accurately at the time. ADR 0015 implements module HTTP routing: it extends
+> `ModuleRegistrationContext` (the `register`-only context) with an `http` route registrar, while
+> `ModuleRuntimeContext` (the `start`/`stop` context this sentence also describes) remains exactly as
+> limited to module ID and capability access as originally decided here. Every other statement in
+> this ADR remains accepted and unchanged.
+
 `ekklesia.module.json` remains the one canonical static manifest and moves to
 `manifestVersion: 2`. Provided capabilities are declarations containing an identifier and an exact
 semantic version. Required and optional capability dependencies map identifiers to semantic-version
@@ -223,6 +223,10 @@ current deployment model but not the final word on it.

 ## Deferred

+> **Cross-reference — see [ADR 0015](0015-static-module-http-routing-and-runtime-lifecycle.md).**
+> Module HTTP route-registration contracts and their production mounting, listed immediately below
+> as deferred, are now implemented. Every other item in this list remains deferred and unimplemented.
+
 Module HTTP route-registration contracts (a module mounting its own endpoints); a
 `ModuleRuntimeContext` authorization service; relationship-derived grant creation (a roster or
 similar module operation using `sourceKind: "relationship"`, not the generic explicit-grant API);
@@ -0,0 +1,286 @@
+# 0015: Static module HTTP routing and production runtime lifecycle
+
+- Status: Accepted
+- Date: 2026-07-24
+- Extends: [0006](0006-versioned-capabilities-and-compiled-module-runtime.md) and
+  [0014](0014-module-permission-declarations-and-platform-registry.md)
+
+## Context
+
+ADR 0006 established the compiled module runtime — deterministic discovery, a staged capability
+registry, dependency-ordered registration and lifecycle, and the injected context's deliberate
+limit to module ID and capability access. ADR 0014 wired module-declared permissions into Core's
+authorization system and explicitly deferred two things: a module mounting its own HTTP routes,
+and `apps/api`'s permission-composition startup retaining the discovered module list for anything
+beyond composition itself. This ADR records the architecture that closes both gaps: a
+framework-neutral route contract a module declares during its existing `register` hook, Core's
+atomic collection of those routes into the same immutable startup snapshot as capabilities, and
+`apps/api`'s production mounting of that snapshot — enforced, origin-checked, and
+response-sanitized — under one platform-owned path prefix.
+
+## Decision
+
+### One contracts-layer, Fetch-based route definition
+
+`packages/contracts/src/module-http.ts` is the sole route contract, consumed identically by Core's
+module runtime and `apps/api`'s mounting adapter — there is no second, parallel definition in
+either layer. It depends only on standard Fetch primitives (`Request`, `Response`), `EkklesiaPrincipal`,
+`ModuleId`, and `PermissionId`; it never imports Hono, Node HTTP types, Better Auth, a database
+client, or any other framework or Core implementation type. A route definition contains exactly
+four fields — `method`, `path`, `permission`, `handler` — validated as an exact-shape object with
+no unknown properties; a module cannot smuggle a baseline, a mount prefix, an absolute path, CORS
+or origin policy, authentication behavior, grant/platform-owner state, middleware, audit metadata,
+or another module's namespace through this contract, because the type has no field for any of
+them. `permission` is accepted as a plain string at the authoring boundary (so a module writes a
+literal identifier with no parse call) and validated and branded to `PermissionId` by the
+contract's own parser, mirroring how `PermissionDeclarationInput`/`PermissionDeclaration` already
+split authoring input from validated output (ADR 0014).
+
+Exactly `GET`, `POST`, `PUT`, `PATCH`, and `DELETE` are authorable, always uppercase; there is no
+`OPTIONS` (the platform owns CORS preflight) and no wildcard or all-methods registration. A path is
+always local to the module and canonical: it begins with `/`, a non-root path never ends with `/`,
+and every segment is either a lowercase kebab-case static segment or a single `:parameterName`
+segment — no empty or repeated slashes, no query string or fragment, no backslash or
+percent-encoding, no dot segment, and no wildcard/catch-all segment, because none of those
+characters can ever satisfy either segment grammar. Malformed input is rejected outright, never
+normalized, so a module can never register a path Core silently reinterpreted.
+
+### Permission ownership is structural, not a runtime policy choice
+
+Every route — including one meant to be publicly reachable — names exactly one permission the
+owning module's own manifest declares (ADR 0014's `manifestVersion: 3` declarations); there is no
+way to construct an unprotected, no-permission route through this contract. A route can never
+supply a baseline: the trusted `public`/`authenticated`/`restricted` baseline comes exclusively
+from the composed platform permission registry at enforcement time, exactly like every other
+permission check in the platform. Public access is expressed by referencing a permission whose own
+manifest declaration has `baseline: "public"`, never by omitting a permission. Core's module
+runtime checks route ownership against only the registering module's own manifest-declared
+permissions — never the composed platform registry, never another module's manifest — so a module
+can never gate a route with Core's or another module's permission; this is a structural
+consequence of what the ownership check is allowed to consult, not a policy a caller could
+misconfigure.
+
+### Atomic validation and publication alongside capabilities
+
+Core's staged registration (ADR 0006) now stages a module's HTTP routes exactly as it already
+stages capability provision: a route is validated and, on failure, rejected immediately at the
+`http.route(...)` call site during `register`, using structured `ModuleRuntimeIssue` codes
+distinguishing invalid shape/handler, invalid method, invalid path, invalid permission identifier,
+an undeclared (unowned) permission, and a duplicate route — never a caught exception's message,
+handler source, or a machine path. A module's routes are merged into the shared, eventually
+published list only after that module's `register` hook returns without throwing *and* every
+capability it declared was actually provided — the same all-or-nothing gate capabilities already
+enforce. `StartedModuleRuntime.routes` is populated, and becomes non-empty, only after every
+discovered module has registered and started successfully; a failed registration or a failed
+startup (with Core's existing reverse-order rollback) publishes no route snapshot at all, exactly
+as no capability registry is published in that case either.
+
+Duplicate detection uses route *shape* — method plus path with every parameter segment collapsed
+to one placeholder — not the parameter's chosen name, so `/events/:eventId` and `/events/:id`
+collide under the same method exactly like the identical route they are. Detection is scoped to
+one module's own routes; two different modules may register the identical local method and path
+without conflict, because the production mount prefix (below) namespaces them apart regardless.
+
+### An immutable, ordered startup snapshot
+
+`StartedModuleRuntime.routes` is a single frozen array of frozen route records, published once at
+startup and never mutated afterward — there is no dynamic route addition or removal while the
+process runs. Its order is deterministic: discovered-module order, then registration order within
+each module. Because a caller-owned route-definition object could otherwise be mutated after
+`http.route(...)` returns, Core never retains the caller's own object — it copies each validated
+field into a freshly frozen record, so mutating the original definition afterward cannot alter the
+published snapshot. Core never invokes a handler during registration or startup; a handler is only
+ever a stored function reference until a route is actually dispatched (a concern entirely owned by
+`apps/api`, below).
+
+### One discovered inventory drives both composition and runtime startup
+
+`prepareStartupModuleInventory` (`apps/api/src/platform-permissions.ts`) discovers the installed
+module inventory exactly once and returns both the discovered module list and the platform
+permission registry composed from it, together. `apps/api`'s production startup
+(`startApi`, `apps/api/src/server.ts`) passes that same discovered list directly to
+`startDiscoveredModuleRuntime` — a Core entry point that performs no discovery of its own and
+preserves the given list's order exactly — so permission composition and executable module
+startup are provably looking at the same installed-module set, never two independently discovered
+ones. `startModuleRuntime` (discover-then-start) remains available as a convenience wrapper for
+callers that do not already have a discovered list; production never calls it. The test-only
+`discoveredModulesOverride` drives both composition and runtime startup identically, for the same
+reason: it stands in for the one real discovered list, never a second, competing one.
+
+Production startup composes in one fixed order: discover the module inventory and compose the
+platform permission registry from it; construct the shared PostgreSQL pool; construct Identity,
+the authorization store, and the evaluator; start the module runtime from that same discovered
+inventory; create the Hono application and mount the started runtime's published routes; bind the
+HTTP server. A discovery or composition failure therefore occurs before any pool, Better Auth
+instance, or executable module code exists; a database/identity construction failure occurs before
+any module runtime starts; and a module runtime or app-construction failure binds no server. Every
+cleanup path preserves the original failure if cleanup itself also fails, matching the sanitized,
+non-masking failure discipline the rest of the platform already follows.
+
+### The platform-owned `/api/v1/modules/<module-id>` namespace, enforced identically to Core's own routes
+
+`apps/api/src/module-http-routes.ts` — the one place in the repository below `apps/api` importing
+Hono for this purpose — mounts a started runtime's published route snapshot under
+`/api/v1/modules/<module-id>`, in publication order, never sorted or otherwise rewritten. A local
+`"/"` maps to the bare module prefix; every other local path appends directly; the platform alone
+decides this mapping, and a module has no way to choose or influence its own mount prefix. This
+ordering is load-bearing, not cosmetic: Hono's router resolves two routes whose patterns overlap at
+the same depth (a static segment and a same-position `:parameter`) by registration order, not by
+static-path specificity, so preserving the runtime's exact publication order is what lets a module
+author's more-specific-first declaration continue to take precedence after mounting. Mounting uses
+one fixed-arity `app.on(method, path, ...middleware, handler)` call per route rather than spreading
+a variable-length handler array — Hono's overload resolution is arity-sensitive, and a spread call
+silently resolves to an unrelated, incompatible overload.
+
+Every mounted route is protected by the identical `requirePermission` middleware Core's own routes
+use (ADR 0013), consulting `route.permission` against the exact same composed platform registry —
+there is no module-specific enforcement path, no wildcard, prefix, namespace, or implication
+matching, and a route's baseline always comes from the registry, never the route. A public
+permission still resolves a principal and traverses the same authorization check as any other
+baseline; only the evaluator's own decision differs. Because the mounted routes and the injected
+registry both derive from the same discovered inventory, every mounted route's permission should
+already be registered; `apps/api` still checks this invariant explicitly at app-construction time
+and fails construction with a fixed, sanitized configuration error if it ever does not hold, rather
+than silently mounting an unenforceable route — `requirePermission`'s own per-request registry
+lookup remains the live, defense-in-depth enforcement regardless of that check.
+
+### Trusted origin, and platform-owned `OPTIONS`/`HEAD`
+
+A state-changing method (`POST`, `PUT`, `PATCH`, `DELETE`) additionally requires an exact trusted
+`Origin`, checked before authorization or the handler ever run — the identical `requireTrustedOrigin`
+mechanism the explicit-grant mutation routes already use (ADR 0013), for the identical reason: CORS
+response headers alone do not stop a browser from *sending* a state-changing cross-origin request,
+only from reading its response. `GET` does not require an `Origin`. `OPTIONS` is never authorable by
+a module and remains entirely platform-owned: the shared CORS middleware intercepts every preflight
+request before any route-specific middleware or handler runs, so a preflight never reaches
+authorization or module code. `HEAD` is not separately authorable either; Hono's own router
+transparently re-dispatches a `HEAD` request through the identical registered `GET` chain and
+strips the response body afterward, so a `HEAD` request is authorized exactly like the `GET` it
+mirrors and cannot bypass anything a direct `GET` would not also bypass. The platform's CORS policy
+advertises `GET`, `POST`, `PUT`, `PATCH`, `DELETE`, and `OPTIONS`, and reflects only an exact
+configured trusted origin — never a wildcard, and never anything module-influenced.
+
+### A frozen, minimal handler context and sanitized failure boundary
+
+A handler receives the unmodified Fetch `Request` (`c.req.raw`, so `Request.url`, headers, method,
+body, and a streaming request all behave normally, and the full query string remains available
+without a competing query abstraction) and a frozen context of exactly `moduleId`, the
+already-authorized `EkklesiaPrincipal`, and an immutable, Hono-decoded parameter record — an empty
+frozen object for a root or fully static route. A handler never receives a Hono `Context`, a
+database connection, the authorization store or evaluator, PostgreSQL, configuration, secrets, or
+any other middleware-internal state. Module code is executable, trusted backend plugin code, not a
+sandboxed boundary — the same trust model ADR 0006 already established for capability registration
+and lifecycle hooks — but its HTTP-facing boundary is still sanitized: a handler that throws,
+rejects, or returns anything other than a `Response` becomes a fixed `500
+{"code":"MODULE_HANDLER_FAILED"}` with `Cache-Control: no-store`, and nothing about the caught
+value, a stack, the module ID, the route's path, or its permission ID is ever included. A
+`Response` a handler deliberately returns — including a 4xx or 5xx one — is never remapped, and a
+streaming body is passed through unread rather than consumed or buffered while headers are
+sanitized.
+
+### Platform-controlled caching and CORS on every module response
+
+The platform remains the sole owner of caching and CORS for a module response: any
+`Access-Control-*` header a handler set is stripped (case-insensitively, since header names are
+themselves case-insensitive) before the response leaves the process, and every module response is
+forced to `Cache-Control: no-store` with a `Vary` that always includes `Origin` and `Cookie` —
+merged case-insensitively so a differently-cased duplicate never appears, and collapsed to a bare
+`*` rather than an invalid combination whenever an existing `Vary` already contains one (RFC 9110
+§12.5.5 forbids combining `*` with any other value) — while any of a handler's own legitimate
+`Vary` values are preserved alongside the forced ones. This is deliberately conservative: even a
+public-baseline handler receives an authorized principal and may personalize its response, so
+until a dedicated module-declared cache-policy contract exists, no module response is ever treated
+as cacheable or origin-independent by default.
+
+### Discovery, Doctor, and `modules:validate` remain manifest-only; production runtime startup does not
+
+Module discovery, Doctor's checks, `modules:validate`, and permission composition continue to read
+only manifests — none of them imports or executes a module's server entrypoint, register hook, or
+any other lifecycle code, exactly as ADR 0006 and ADR 0014 established. A *successful* production
+runtime startup is the one deliberate exception: it imports each installed module's compiled server
+entrypoint and runs its `register` and `start` hooks, because that is the only way a module's
+declared routes and capabilities become real, dispatchable behavior. Entrypoint modules remain
+trusted backend plugins, not a sandbox boundary (ADR 0006); their top-level ESM evaluation must
+remain side-effect-free, because ESM evaluation cannot be rolled back or unloaded once it has run —
+this was already a hard requirement for capability registration and remains exactly as hard a
+requirement now that routes are declared the same way, during the same hook.
+
+### Restart-based static installation, and ordered runtime shutdown
+
+Installing, removing, or editing a module's routes takes effect only on the next API restart,
+exactly like permission composition (ADR 0014) — there is no hot installation, removal, or dynamic
+route mutation while the process runs. Removing a module makes its former routes return the
+platform's ordinary `404 {"code":"NOT_FOUND"}`, the same fallback every unmatched path already
+receives. `RunningApi`'s shutdown stops accepting new HTTP work and drains in-flight requests
+first, then stops the module runtime, then closes the shared PostgreSQL pool — in that order, so no
+module resource stops while a route handler might still be executing. One memoized shutdown promise
+is shared by every concurrent or later caller; each of the three steps runs at most once regardless
+of how many times `shutdown()` is called. Unlike a startup-failure cleanup path (which always
+swallows a secondary cleanup failure so it never masks the original error), a module-stop failure
+during *normal* shutdown is not swallowed — it is a genuine result a caller should observe — but
+database cleanup still always completes first, so a stop failure never leaves the pool open.
+
+## Alternatives
+
+- **Hono or another framework's own request/response/routing types in the contracts layer** was
+  rejected: it would leak an implementation-layer framework choice into the one public contract
+  every module and Core depend on, and would make swapping the HTTP transport a breaking contract
+  change instead of an internal one.
+- **Declaring routes in the static module manifest** (alongside capabilities and permissions) was
+  rejected: a route's `handler` is executable behavior, not inert data a manifest can express
+  without executing module code, and duplicating the same route between a manifest and the runtime
+  definition would create two sources of truth that could silently drift.
+- **Permissionless routes, or a route/handler that selects its own baseline** were rejected outright
+  by the contract's shape: there is no field for either, so no caller can construct a route that
+  omits a permission or asserts its own trust level.
+- **An arbitrary or module-chosen mount prefix** was rejected in favor of a single platform-owned
+  `/api/v1/modules/<module-id>` namespace: a module choosing its own path risks colliding with
+  Core's own routes or another module's, and removes the platform's ability to reason about the
+  complete route surface from one place.
+- **A second module discovery pass, or a second route/runtime registry, for HTTP routes
+  specifically** was rejected in favor of reusing the exact discovery Phase 5A already performs and
+  staging routes inside the same `StartedModuleRuntime` capabilities already publish through —
+  avoiding two independently discovered inventories that could disagree, and two registry
+  implementations that could drift.
+- **Module-owned authorization, CORS, or origin-checking middleware** was rejected: every module
+  route is enforced through the identical, already-audited `requirePermission`/`requireTrustedOrigin`
+  mechanism Core's own routes use, so there is exactly one enforcement mechanism to reason about and
+  audit, not one per module.
+- **`OPTIONS` or `HEAD` as module-authorable methods** were rejected: `OPTIONS` is inseparable from
+  the platform's own CORS policy, and `HEAD` is fully and correctly served by Hono's own transparent
+  `GET`-chain re-dispatch; making either authorable would only create a second, competing code path
+  for behavior the platform already provides correctly.
+- **Dynamic or hot route mutation** (adding, removing, or replacing a route while the process runs)
+  was rejected for this phase: it would reopen the same concurrent-mutation and partial-update
+  hazards ADR 0014 already rejected for permission composition, for no benefit the current
+  deployment model needs.
+- **A module-declared cache policy** (letting a route specify its own `Cache-Control`/`Vary`
+  behavior) was rejected for this phase: the conservative default (`no-store`, vary on `Origin` and
+  `Cookie`) is always correct, while a wrong module-declared policy could leak one user's
+  personalized response to another; a real cache-policy contract is deferred, deliberately, rather
+  than guessed at now.
+
+## Consequences
+
+A module gains a real, dispatchable HTTP surface the moment its `register` hook declares routes
+against permissions its own manifest already declares — no second registration step, no
+module-specific transport code to write. The integration boundary is safe by construction: the
+contracts-layer shape structurally prevents a permissionless route or a module-asserted baseline,
+Core's ownership check structurally prevents borrowing another owner's permission, and `apps/api`'s
+mounting reuses exactly the enforcement, origin-checking, and response-sanitization machinery
+already audited for Core's own routes. The operational cost mirrors ADR 0014's: every module
+inventory or route change requires an API restart to take effect, and — because production startup
+now deliberately imports and executes trusted module entrypoints, not merely their manifests — a
+module's compiled server code must be as trustworthy as any other backend plugin code Core already
+runs, since nothing about this design sandboxes it.
+
+## Deferred
+
+Module database or Drizzle access; module storage access; jobs and workflow/event automation;
+module-owned configuration and secrets services; a `ModuleRuntimeContext` authorization service;
+relationship-derived grant operations; reinstall/reactivation semantics for a permission or route
+whose owning module was previously removed; roles, groups, teams, and tenants; an owner-management
+HTTP endpoint; service accounts and API tokens for non-browser automation; a native-client
+trusted-origin exemption policy; a module-declared cache-policy contract; hot module
+installation, removal, or reloading; Surfaces and UI; and real product-module endpoints. None of
+these are implemented by, or required for, the architecture this ADR records.
@@ -23,3 +23,4 @@ ADRs capture durable choices that affect more than one package or phase.
 - [0012: Production-equivalent identity origin/CSRF protection under test](0012-identity-origin-csrf-protection-under-test.md) — Accepted
 - [0013: Core authorization, permission registry, and platform-owner bootstrap](0013-core-authorization-and-owner-bootstrap.md) — Accepted
 - [0014: Module permission declarations and platform permission registry](0014-module-permission-declarations-and-platform-registry.md) — Accepted
+- [0015: Static module HTTP routing and production runtime lifecycle](0015-static-module-http-routing-and-runtime-lifecycle.md) — Accepted
@@ -57,6 +57,7 @@ No real values are shown here — configure per environment and never commit the
 | `POST\|GET /api/auth/*` | Better Auth (mounted directly) | Better Auth's own request/response shapes pass through unmodified — see [Better Auth's email/password docs](https://www.better-auth.com/docs/authentication/email-password) for the exact endpoints (`/sign-up/email`, `/sign-in/email`, `/sign-out`, `/get-session`, ...). |
 | `GET /api/v1/principal` | Ekklesia | Returns the minimal `EkklesiaPrincipal` contract as JSON. `Cache-Control: no-store`. |
 | `GET\|POST /api/v1/grants*` | Ekklesia | Explicit authorization grant management, gated by `core.authorization.grants.manage`. See [Authorization](authorization.md#explicit-grant-http-api). |
+| `/api/v1/modules/<module-id>/*` | Installed modules | Every route an installed module registered during its `register` hook, gated by that route's own declared permission. See [Module HTTP routes](#module-http-routes). |

 Better Auth's handler is unreachable outside `/api/auth/*`; every other unmatched path returns a
 deterministic `404 {"code":"NOT_FOUND"}`.
@@ -206,17 +207,74 @@ trusted-proxy IP policy is configured, Better Auth may fall back to a single sha
 rather than a genuine per-client bucket. This is not yet the final, distributed, production-grade
 abuse-control design.

-## Module permission discovery at startup
+## Module discovery, permission composition, and module runtime startup

-Before any database pool, Better Auth instance, or HTTP server exists, `startApi()` discovers
-every installed module's manifest and composes the one immutable platform permission registry
-(Core's own declarations plus every module's) that the rest of startup — and every subsequent
-request — enforces against. A discovery or composition failure (an invalid manifest, a module
-claiming the reserved `core.*` permission namespace, a duplicate permission declaration, ...) fails
-startup outright, before there is anything to close; startup never falls back to a Core-only
-registry. See [Authorization](authorization.md#api-startup-discovery-composition-and-enforcement)
-for the full flow, and [Module development](module-development/README.md) for the manifest shape
-that produces these declarations.
+`startApi()` composes production in one fixed order:
+
+1. Discover every installed module's manifest exactly once and compose the one immutable platform
+   permission registry (Core's own declarations plus every module's) — `prepareStartupModuleInventory`,
+   `apps/api/src/platform-permissions.ts`.
+2. Construct the one shared PostgreSQL pool.
+3. Construct the Core identity runtime, authorization store, and evaluator.
+4. Start the module runtime from that exact same discovered inventory
+   (`startDiscoveredModuleRuntime`) — modules are never rediscovered for this step.
+5. Create the Hono application, mounting the started module runtime's published routes.
+6. Bind the HTTP server.
+
+Discovery and permission composition happen before any pool, Better Auth instance, module
+entrypoint import, or HTTP server exists, so a discovery or composition failure (an invalid
+manifest, a module claiming the reserved `core.*` permission namespace, a duplicate permission
+declaration, ...) fails startup outright, before there is anything to close; startup never falls
+back to a Core-only registry. Core infrastructure exists before any executable module lifecycle
+code runs, and every module route is published only after the *entire* module runtime has
+registered and started successfully, so no request can ever reach a module before every module has
+started. See [Authorization](authorization.md#api-startup-discovery-composition-and-enforcement)
+for the permission-composition detail, and [Module development](module-development/README.md) for
+the manifest shape that produces these declarations.
+
+Unlike discovery/composition/Doctor/`modules:validate` (which only ever read manifests), a
+successful production startup does import each module's compiled server entrypoint and run its
+`register`/`start` hooks — this is the one place in the platform that deliberately executes module
+code, and only after every other startup step already listed has succeeded.
+
+## Module HTTP routes
+
+An installed module's routes (declared via `http.route(...)` in its `register` hook — see
+[Module development](module-development/README.md#http-routes) for the module-authoring contract)
+are mounted under `/api/v1/modules/<module-id>`, in the module runtime's published order, by
+`apps/api/src/module-http-routes.ts`. Mounting never invokes a handler.
+
+- **Enforcement.** Every route runs through the identical `requirePermission` middleware Core's own
+  routes use, with the route's own declared permission id as the only permission ever consulted —
+  its trusted baseline always comes from the composed platform registry, never from the route or
+  the request. A `public`, `authenticated`, and `restricted` module permission are enforced through
+  the exact same path; a public-baseline route still resolves and receives an authorized principal.
+- **Trusted origin.** `POST`, `PUT`, `PATCH`, and `DELETE` module routes additionally require an
+  exact trusted `Origin` (see [Origin, CORS, and cookies](#origin-cors-and-cookies)) before
+  authorization ever runs, exactly like the existing grants-mutation routes. `GET` does not require
+  one. `OPTIONS` remains entirely platform-owned: a module cannot register it, and a CORS preflight
+  never reaches authorization or a handler. `GET` inherits Hono's own implicit `HEAD` handling
+  (same permission check, response body stripped); a module cannot separately author `HEAD`.
+- **Handler input.** A handler receives the raw Fetch `Request` (so `Request.url`, headers, and
+  body all behave normally, and the full query string remains available) plus a frozen context of
+  exactly `moduleId`, the authorized `EkklesiaPrincipal`, and frozen, Hono-decoded path parameters
+  (an empty frozen object for a route with none) — never a Hono `Context`, a database connection,
+  the authorization store, storage, jobs, configuration, or secrets.
+- **Handler failure.** A handler that throws, rejects, or returns anything other than a `Response`
+  becomes a fixed `500 {"code":"MODULE_HANDLER_FAILED"}` with `Cache-Control: no-store` — never the
+  caught value, a stack, the route's path or permission id, or the module id. A `Response` a
+  handler deliberately returns — including a 4xx/5xx one — passes through unchanged.
+- **CORS and caching.** The platform remains the sole owner of CORS for module routes exactly like
+  every other `/api/v1/*` route (see [Origin, CORS, and cookies](#origin-cors-and-cookies), now
+  additionally advertising `PUT`/`PATCH`/`DELETE`); any CORS-control header a handler sets on its
+  own response is stripped before the response leaves the process. Every module response is forced
+  to `Cache-Control: no-store` and a `Vary` that always includes `Origin` and `Cookie` (a handler's
+  own legitimate `Vary` values are preserved alongside those) — deliberately conservative until a
+  dedicated cache-policy contract exists, since even a public-baseline handler receives an
+  authorized principal and may personalize its response.
+- **Static snapshot.** Routes are part of the same static startup snapshot as the permission
+  registry: installing, removing, or editing a module's routes takes effect only on the next API
+  restart. Removing a module makes its former routes return the ordinary `404 {"code":"NOT_FOUND"}`.

 ## Database connection limits

@@ -239,17 +297,25 @@ not two.
 `startApi()` (the composition function `apps/api/src/server.ts` exports, used by both the
 executable entry point and tests) returns `{app, server, shutdown}`. `shutdown()` memoizes one
 shared promise the first time it is called: every caller, concurrent or sequential, awaits the
-exact same listener-drain-then-pool-close operation, and that operation runs exactly once no matter
-how many times `shutdown()` is called. It stops the HTTP listener from accepting new connections and
-lets in-flight requests finish, then closes the one shared PostgreSQL pool (identity and
-authorization both read from it — see
-[Authorization](authorization.md#shared-database-composition)). The executable entry point's
-`SIGINT`/`SIGTERM` wiring is extracted into `installShutdownSignalHandlers(running, exit)` — the
-same function production composition uses, but independently testable with a fake `running`/`exit`
-so a test can trigger "a signal arrived" without sending a real process signal or invoking the real
-`process.exit`. A startup failure after the database pool was already created (identity
-construction failure, or the server failing to bind its listen address) always closes that pool
-before the failure propagates.
+exact same operation, and that operation runs exactly once no matter how many times `shutdown()`
+is called. In order: it stops the HTTP listener from accepting new connections and lets in-flight
+requests finish; then stops the module runtime (so no module resource stops while a route handler
+might still be in flight); then closes the one shared PostgreSQL pool (identity and authorization
+both read from it — see [Authorization](authorization.md#shared-database-composition)). Unlike a
+startup-failure cleanup path (below), a module-stop failure here is not swallowed — it is a
+genuine result a caller should observe — but pool cleanup always still runs first, so a stop
+failure never leaves the pool open. The executable entry point's `SIGINT`/`SIGTERM` wiring is
+extracted into `installShutdownSignalHandlers(running, exit)` — the same function production
+composition uses, but independently testable with a fake `running`/`exit` so a test can trigger "a
+signal arrived" without sending a real process signal or invoking the real `process.exit`.
+
+A startup failure after the database pool was already created always closes that pool before the
+failure propagates: identity/authorization construction failing (no module runtime was started
+yet); the server failing to bind its listen address; or an app-construction failure, both of which
+also stop the module runtime first, since it may have already started successfully. A module
+load/register/start failure uses Core's own existing rollback (already-started modules stop, in
+reverse order, before the failure propagates) and then closes the pool — there is no separate
+runtime handle to stop in that case, since `startDiscoveredModuleRuntime` never returned one.

 ## A real signup → sign-in → principal → sign-out transcript

@@ -16,14 +16,15 @@ for the durable architectural decisions this page describes in more implementati

 An operator can bootstrap exactly one platform owner for a deployment; a platform owner (or anyone
 they delegate to) can create, list, and revoke *explicit* authorization grants over HTTP for any
-registered permission, Core-owned or module-owned; and every enforced route fails closed on
-infrastructure trouble instead of silently allowing or denying. It is **not** possible to manage
-roles, groups, teams, or tenants; there is no owner-management HTTP endpoint (revoking or
-re-granting platform-owner status is not exposed at all); there are no service accounts or API
-tokens, so only cookie-authenticated browser callers can reach the mutation routes; a module cannot
-yet mount its own HTTP routes; and relationship-derived grants (for example, automatic access from
-a roster assignment) cannot yet be created by anything in this repository — the generic grants API
-structurally cannot create or revoke them either.
+registered permission, Core-owned or module-owned; a module can register its own HTTP routes and
+have them mounted, enforced, and reachable in production (see
+[API](api.md#module-http-routes)); and every enforced route fails closed on infrastructure trouble
+instead of silently allowing or denying. It is **not** possible to manage roles, groups, teams, or
+tenants; there is no owner-management HTTP endpoint (revoking or re-granting platform-owner status
+is not exposed at all); there are no service accounts or API tokens, so only cookie-authenticated
+browser callers can reach mutation routes, Core-owned or module-owned; and relationship-derived
+grants (for example, automatic access from a roster assignment) cannot yet be created by anything
+in this repository — the generic grants API structurally cannot create or revoke them either.

 ## Core authorization schema and store

@@ -105,27 +106,37 @@ integration layer depends on authorization).

 ## API startup: discovery, composition, and enforcement

-`apps/api` builds its production permission registry from the complete installed-module inventory
-every time it starts, in a fixed order, before anything else:
+`apps/api` builds its production permission registry, and starts the module runtime, from the
+exact same installed-module inventory every time it starts, in a fixed order, before anything
+else:

 1. Resolve module-discovery configuration (the repository's `modules/` directory, and the
   platform/Module SDK versions from their own `package.json` files).
-2. Discover installed modules (`discoverModules`).
-3. Compose the platform permission registry (`composePlatformPermissionRegistry`).
+2. Discover installed modules exactly once (`discoverModules`).
+3. Compose the platform permission registry from that exact discovered list
+   (`composePlatformPermissionRegistry`).
 4. Construct the shared PostgreSQL pool.
-5. Construct Identity and Authorization.
-6. Create the Hono application, injecting the composed registry.
-7. Bind the HTTP server.
+5. Construct Identity, the authorization store, and the evaluator.
+6. Start the module runtime from that same discovered list (`startDiscoveredModuleRuntime`) —
+   modules are never rediscovered for this step.
+7. Create the Hono application, injecting the composed registry and mounting the started module
+   runtime's published routes (see [API](api.md#module-http-routes)).
+8. Bind the HTTP server.

-`apps/api/src/platform-permissions.ts`'s `composeStartupPermissionRegistry` performs steps 1–3.
-Discovery and composition happen strictly before any pool, Better Auth instance, or HTTP server
-exists, so a failure there — an invalid manifest, a broken dependency graph, a module claiming the
-reserved `core.*` namespace, or a duplicate permission declaration — leaves nothing to close: it
-propagates directly out of `startApi()`, and startup never falls back to `CORE_PERMISSION_REGISTRY`
-or any Core-only registry. The repository root is resolved from this compiled/source file's own
-location (two directories up from `apps/api/dist/*.js` or `apps/api/src/*.ts`, which sit at
-identical depth), never `process.cwd()` — a package-scoped test run has `apps/api` as its working
-directory, which would otherwise point discovery at the wrong `modules/` directory.
+`apps/api/src/platform-permissions.ts`'s `prepareStartupModuleInventory` performs steps 1–3,
+returning both the discovered module list and the composed registry so step 6 can start the module
+runtime from that identical list rather than rediscovering modules a second time.
+(`composeStartupPermissionRegistry` remains available as a registry-only convenience wrapper
+around it, for callers — Doctor, `modules:validate`, existing tests — that only need the
+registry.) Discovery and composition happen strictly before any pool, Better Auth instance, module
+entrypoint import, or HTTP server exists, so a failure there — an invalid manifest, a broken
+dependency graph, a module claiming the reserved `core.*` namespace, or a duplicate permission
+declaration — leaves nothing to close: it propagates directly out of `startApi()`, and startup
+never falls back to `CORE_PERMISSION_REGISTRY` or any Core-only registry. The repository root is
+resolved from this compiled/source file's own location (two directories up from
+`apps/api/dist/*.js` or `apps/api/src/*.ts`, which sit at identical depth), never `process.cwd()`
+— a package-scoped test run has `apps/api` as its working directory, which would otherwise point
+discovery at the wrong `modules/` directory.

 The resulting registry is a **static, immutable snapshot** taken once at startup. There is no hot
 installation, removal, or dynamic mutation of installed modules or their permissions while the
@@ -148,10 +159,11 @@ consults the registry for a grant that already exists — revocation is keyed to
 and source kind, not to whether its permission is currently registered — so a manager can still
 revoke a historical grant for a now-unregistered permission.

-Module HTTP route registration (a module owning its own mounted endpoints) and relationship-derived
-grant creation both remain deferred, unrelated slices — this work only makes a module's *declared*
-permission usable through Core's existing, generic explicit-grant HTTP API and enforcement
-middleware.
+A module's own mounted HTTP routes (`/api/v1/modules/<module-id>/*`) are enforced through this
+identical registry and `requirePermission` middleware — see [API](api.md#module-http-routes) for
+the route-mounting contract. Relationship-derived grant creation remains a deferred, unrelated
+slice — this work only makes a module's *declared* permission usable through Core's existing,
+generic explicit-grant HTTP API, enforcement middleware, and now its own mounted routes.

 ## Doctor and modules:validate

@@ -446,12 +458,34 @@ there are or whether the failure happened during startup.
  `403` and `store.createGrant` never called, exact server-derived-argument assertions,
  sourceKind-filtered revoke returning 404 for a non-explicit grant, origin enforcement, and
  store-error mapping.
+- `apps/api/tests/module-http-routes.test.ts` — the production route-mounting contract: exact
+  prefix/path joining (including the non-trailing-slash root case), every supported method,
+  independent same-path routes across two modules, deterministic static-versus-parameterized
+  resolution by published order, request/handler adaptation (raw `Request`, frozen context, decoded
+  and frozen path parameters, empty frozen params for static/root routes), the registry's exact
+  baseline for `public`/`authenticated`/`restricted` module permissions, denial/infrastructure-
+  failure paths never invoking the handler, `ModuleRouteConfigurationError` for an inconsistent
+  route/registry snapshot, trusted-origin enforcement for state-changing methods, CORS (advertised
+  methods, no reflection for an untrusted origin, no authorization or handler invocation on
+  preflight), fixed sanitized `500` for a throwing/rejecting/non-`Response`-returning handler with
+  no raw leakage, a valid module-owned 4xx/5xx response passing through unchanged, forced
+  `Cache-Control`/`Vary` with a handler's own `Vary` preserved, stripped module-supplied CORS
+  headers, `HEAD` traversing the same permission middleware as `GET` with no body, and unmatched
+  paths/zero-route/no-handler-during-construction behavior.
 - `apps/api/tests/lifecycle.test.ts` — shared-pool-closes-exactly-once coverage described above,
  plus module-permission composition at startup: discovery/composition run before any pool,
  Better Auth instance, or HTTP server is constructed; a discovery failure, a reserved-namespace
  failure, and a generic duplicate-declaration failure each create zero pools/Better Auth
  instances/servers and remain distinguishable from one another; zero installed modules still
-  succeeds; and import safety for `platform-permissions.ts`.
+  succeeds; and import safety for `platform-permissions.ts`. A dedicated block covers module
+  *runtime* startup and shutdown against real, working (non-throwing) fixture modules: permission
+  composition and module runtime startup share the exact same discovered inventory, route mounting
+  order matches discovery order, a load/register/start failure each close the pool exactly once and
+  bind no server (preserving Core's own rollback for a start failure), an app-construction failure
+  and a bind failure both stop the module runtime before closing the pool, normal shutdown stops the
+  server/module-runtime/pool in that exact order, a module stop failure still runs pool cleanup
+  before the shutdown rejection surfaces, and a direct `discoveredModulesOverride` drives both
+  composition and runtime startup identically.
 - `core/tests/authorization-evaluator.test.ts` — includes a malformed permission id denying under
  every baseline (`public`, `authenticated`, `restricted`), never just `restricted`, and never
  consulting the grant or platform-owner ports for `public`/`authenticated`.
@@ -466,16 +500,23 @@ there are or whether the failure happened during startup.
  invisible to LIST and unreachable by REVOKE, and an infrastructure-failure scenario (database
  dropped out from under a live session) asserting a `503` rather than a false `403` or `200`.
 - `apps/api/tests/api-http.integration.ts`, "installed module permission end-to-end" (live
-  PostgreSQL) — a real temporary module fixture (structurally valid manifest, a server entrypoint
-  that throws if ever imported) proves the complete chain against a real API process and real
-  Doctor run: Doctor recognizes the installed module and passes permission composition without
-  executing its entrypoint; API startup discovers the fixture and makes its declared permission
-  enforceable; a bootstrapped platform owner creates a real explicit grant for the module's
-  permission with an atomic audit row recorded under its exact declared id; a well-formed
-  permission absent from the composed registry is rejected with no grant or audit write; and,
-  after a clean shutdown and restart with the module absent, the same permission can no longer be
-  newly granted while the earlier, still-unrevoked grant remains listed — with ordinary identity
-  HTTP behavior (sign-up, sign-in, principal resolution) unaffected throughout.
+  PostgreSQL) — a real temporary module fixture (structurally valid manifest; a real, working
+  server entrypoint recording register/start/stop markers instead of throwing, and declaring a
+  restricted `GET /events/:eventId` route plus a restricted, state-changing `POST /events` route
+  against its own manifest permission) proves the complete chain against a real API process and
+  real Doctor run: Doctor recognizes the installed module and passes permission composition
+  without executing its entrypoint (an empty marker set); a successful `startApi()` discovers the
+  same fixture, imports/registers/starts its runtime exactly once, and makes its declared
+  permission enforceable; a bootstrapped platform owner creates a real explicit grant for the
+  module's permission with an atomic audit row recorded under its exact declared id; the module's
+  own mounted route denies an anonymous caller and then serves the newly granted owner with the
+  decoded path parameter and authenticated principal; the module's state-changing route requires a
+  trusted `Origin` exactly like the platform's own mutation routes; a well-formed permission absent
+  from the composed registry is rejected with no grant or audit write; and, after a clean shutdown
+  (module stop invoked exactly once) and restart with the module absent, its former route returns
+  the ordinary `404`, the same permission can no longer be newly granted, and the earlier,
+  still-unrevoked grant remains listed — with ordinary identity HTTP behavior (sign-up, sign-in,
+  principal resolution) unaffected throughout.

 Run the focused suites:

@@ -487,10 +528,11 @@ pnpm test:migrations:integration   # requires Docker

 ## Next phase

-Deliberately deferred, unrelated slices — see
+Module HTTP route registration and production mounting (see
 [ADR 0014](../architecture/decisions/0014-module-permission-declarations-and-platform-registry.md#deferred)
-for the complete list: module HTTP route-registration contracts (a module mounting its own
-endpoints), a module runtime-context authorization service, relationship-derived grant creation
+for the deferral this closes) is now implemented — see [API](api.md#module-http-routes) and
+[Module development](module-development/README.md#http-routes). Deliberately deferred, unrelated
+slices remain: a module runtime-context authorization service, relationship-derived grant creation
 itself (a roster or similar module operation, not the generic grants API), reinstall/reactivation
 policy for a permission whose owning module was previously removed, roles/groups/teams/tenants, an
 owner-management HTTP endpoint, and service accounts/API tokens for non-browser automation.
@@ -22,13 +22,18 @@ error-only sanitized logger that strips Better Auth's own message and arguments
 they contain, pinned 8–128 password-length bounds, sanitized failures, and that a database outage
 during principal resolution is never silently reported as anonymous), and Core migration discovery
 (deterministic ordering, the reserved `core` identity, and collision rejection) — all without a
-live database. `apps/api`'s own unit tests cover its pure Hono app factory (route shapes, CORS
-allow/deny/preflight, deterministic 404 and sanitized error responses), its runtime configuration,
-its idempotent shutdown lifecycle (concurrent callers share one server-close-then-pool-close
-promise; a startup failure after the pool was already created still closes it; `SIGINT`/`SIGTERM`
-wiring is exercised through an injectable exit function rather than the real `process.exit`), and
-that importing any of its modules — including the executable server module without calling its
-exported `main` — never reads the environment, connects to PostgreSQL, or starts a server.
+live database. `apps/api`'s own unit tests cover its pure Hono app factory (route shapes, module
+route mounting/enforcement/CORS/response sanitization, CORS allow/deny/preflight, deterministic 404
+and sanitized error responses), its runtime configuration, its idempotent shutdown lifecycle
+(concurrent callers share one server-close-then-module-runtime-stop-then-pool-close promise; a
+module-stop failure never prevents pool cleanup; a startup failure after the pool was already
+created still closes it, stopping the module runtime first if it had already started;
+`SIGINT`/`SIGTERM` wiring is exercised through an injectable exit function rather than the real
+`process.exit`), and that importing any of its modules — including the executable server module
+without calling its exported `main` — never reads the environment, connects to PostgreSQL, imports
+a module entrypoint, or starts a server. Real, working (non-throwing) module fixtures prove
+production module-runtime startup/shutdown ordering and cleanup against a mocked pool/Better
+Auth/server — see [Authorization](authorization.md#tests).

 `pnpm verify` is intentionally Docker-free. It never plans or applies migrations against a live
 database.
@@ -177,6 +177,84 @@ Entrypoint imports must have no top-level side effects. Modules are trusted back
 evaluation cannot be rolled back. Keep registration declarative; open resources in `start` and
 close them in `stop`.

+## HTTP routes
+
+A module registers plain Fetch (`Request` in, `Response` out) route handlers during `register`,
+through the `http` registrar `ModuleRegistrationContext` provides alongside `capabilities`:
+
+```ts
+import { defineModuleRuntime } from "@ekklesia/module-sdk";
+
+export default defineModuleRuntime({
+  id: "calendar",
+  version: "0.1.0",
+
+  register({ capabilities, http }) {
+    capabilities.provide("calendar.events", calendarEvents);
+
+    http.route({
+      method: "GET",
+      path: "/events/:eventId",
+      permission: "calendar.events.read",
+      async handler(request, context) {
+        return Response.json({
+          eventId: context.params.eventId,
+          principal: context.principal.kind,
+        });
+      },
+    });
+  },
+});
+```
+
+A route definition has exactly four fields — `method`, `path`, `permission`, `handler` — and nothing
+else; an unknown field (a baseline, a mount prefix, CORS/origin policy, middleware, audit metadata,
+authentication behavior, or another module's namespace) fails registration outright rather than
+being ignored. `method` is one of `GET`, `POST`, `PUT`, `PATCH`, `DELETE`, always uppercase; there is
+no `OPTIONS` (the platform owns CORS preflight) and no wildcard/all-method registration.
+
+`path` is local to the module, never the path a caller actually sends. The platform alone owns the
+production mount prefix, `/api/v1/modules/<module-id>`: `"/"` is the module's own root, `"/events"`
+means `/api/v1/modules/calendar/events`, and `"/events/:eventId"` is a parameterized route using the
+same `:name` syntax a caller's request is matched against. A canonical path begins with `/`, a
+non-root path never ends with `/`, and every segment is either a lowercase kebab-case static segment
+or one `:parameterName` segment — no empty or repeated slashes, no query string or fragment, no
+backslash or percent-encoding, no dot segments, and no wildcard/catch-all segment. A malformed path
+is rejected outright, never silently normalized.
+
+Every route — including a route meant to be publicly reachable — names exactly one `permission` the
+owning module's own manifest declares; there is no way to register an unprotected, no-permission
+route. A module cannot supply a baseline directly: the permission's trusted `public`, `authenticated`,
+or `restricted` baseline always comes from the composed platform registry, exactly like any other
+enforcement decision. Public access is therefore expressed by referencing a permission whose manifest
+declaration has `baseline: "public"`, never by omitting a permission. A module may only reference a
+permission its own manifest declares — never a Core-owned permission, and never another module's —
+so it can never gate a route behind authority it does not itself own. The same local path may be
+registered under more than one method, but registering the same module twice under the identical
+method and path (or two paths that are identical once every parameter is treated as an anonymous
+placeholder, such as `/events/:eventId` and `/events/:id` under `GET`) fails as a duplicate route.
+
+The handler receives the standard `Request` plus a context of exactly `moduleId`, the caller's
+already-authorized `EkklesiaPrincipal`, and the immutable decoded path parameters — never a database
+connection, authorization store, grant/platform-owner state, storage, jobs, configuration, secrets,
+a framework-specific request context, or a raw Better Auth session. The full query string remains
+available through `Request.url`; there is no separate query or body abstraction.
+
+Core defines, validates, and collects routes into `StartedModuleRuntime`'s immutable route
+snapshot — it never invokes a handler itself. `apps/api` mounts that exact snapshot into production
+at startup, under the `/api/v1/modules/<module-id>` prefix described above: every route is enforced
+through the identical `requirePermission` middleware Core's own routes use, a state-changing method
+(`POST`/`PUT`/`PATCH`/`DELETE`) additionally requires a trusted `Origin` before authorization ever
+runs, and a handler that throws, rejects, or returns something other than a `Response` becomes a
+fixed, sanitized `500 {"code":"MODULE_HANDLER_FAILED"}` — never the caught value, a stack, the
+route's path, its permission id, or the module id. The platform remains the sole owner of CORS and
+caching for every module route: a handler-supplied CORS-control header is stripped, and every
+module response is forced to `Cache-Control: no-store` with `Vary: Origin, Cookie` (in addition to
+any of the handler's own legitimate `Vary` values) until a dedicated cache-policy contract exists —
+deliberately conservative, since even a public-baseline handler still receives an authorized
+principal and may personalize its response. See [API](../development/api.md#module-http-routes) for
+the full production mounting, enforcement, and error-response contract.
+
 ## Drizzle schema definition

 A module with tables keeps the generator-facing declarations in `src/schema/tables.ts`:
@@ -327,10 +405,12 @@ not misreported as a successful check.

 Core completes discovery before importing any server entrypoint. It then loads and verifies every
 runtime definition before running hooks, registers all modules dependency-first into an unpublished
-staged capability registry, and starts them in the same order. Shutdown is reverse-order. If a later
-module fails to start, Core stops already-started modules in reverse order and reports any cleanup
-failures without leaking caught exceptions or machine paths. A failing `start` hook must clean up
-its own partial work before rejecting.
+staged capability registry and an unpublished staged HTTP route list side by side, and starts them in
+the same order. Neither the capability registry nor the route list is published — visible on
+`StartedModuleRuntime` — unless every module registers and starts successfully. Shutdown is
+reverse-order. If a later module fails to start, Core stops already-started modules in reverse order
+and reports any cleanup failures without leaking caught exceptions or machine paths. A failing
+`start` hook must clean up its own partial work before rejecting.

 ## Start from the template

@@ -1,6 +1,7 @@
 export * from "./authorization.js";
 export * from "./identifiers.js";
 export * from "./identity.js";
+export * from "./module-http.js";
 export * from "./module-lifecycle.js";
 export * from "./module-manifest.js";
 export * from "./module-migration.js";
@@ -0,0 +1,258 @@
+import { z } from "zod";
+import type { EkklesiaPrincipal } from "./identity.js";
+import { type ModuleId, type PermissionId, permissionIdSchema } from "./identifiers.js";
+
+// Not imported from `./module-runtime.js`'s own `Awaitable` (structurally identical) — importing
+// it would create a source dependency cycle with that module, which also imports from this one for
+// `ModuleHttpRouteRegistrar`. `scripts/check-boundaries.ts` rejects any source cycle, including one
+// formed only by `import type`, so this tiny, fixed-shape utility type is kept private here instead.
+type Awaitable<Value> = Value | PromiseLike<Value>;
+
+/** The exact, canonical HTTP methods a module route may declare. Uppercase only — a module never
+ * gets `OPTIONS` (the platform owns CORS preflight) or a wildcard/all-methods registration. */
+export const MODULE_HTTP_METHODS = ["DELETE", "GET", "PATCH", "POST", "PUT"] as const;
+
+export type ModuleHttpMethod = (typeof MODULE_HTTP_METHODS)[number];
+
+const moduleHttpMethods: ReadonlySet<string> = new Set(MODULE_HTTP_METHODS);
+
+export function isModuleHttpMethod(value: unknown): value is ModuleHttpMethod {
+  return typeof value === "string" && moduleHttpMethods.has(value);
+}
+
+const MODULE_ROUTE_PATH_MAX_LENGTH = 256;
+const staticSegmentPattern = /^[a-z0-9]+(?:-[a-z0-9]+)*$/u;
+const parameterSegmentPattern = /^:[a-z][a-zA-Z0-9]*$/u;
+
+/**
+ * A module-local route path — never the production-mounted `/api/v1/modules/<module-id>` path a
+ * caller actually sends (`apps/api/src/module-http-routes.ts` owns that mapping). Not branded
+ * (unlike `PermissionId`): like `PackageRelativePath`,
+ * this is a validated location, not an opaque cross-system identifier. `"/"` is the module root;
+ * any other canonical path begins with `/`, never ends with `/`, and is composed only of lowercase
+ * kebab-case static segments or single `:parameterName` segments — no empty or repeated slashes, no
+ * query string or fragment, no backslash or percent-encoding, no dot segments, and no wildcard or
+ * catch-all segment, since none of those can ever match either segment grammar. Malformed input is
+ * rejected outright rather than normalized, so a module can never register a path Core silently
+ * reinterpreted.
+ */
+export const moduleRoutePathSchema = z
+  .string()
+  .max(MODULE_ROUTE_PATH_MAX_LENGTH)
+  .superRefine((value, context) => {
+    if (
+      !value.startsWith("/") ||
+      value.includes("\\") ||
+      value.includes("%") ||
+      value.includes("?") ||
+      value.includes("#")
+    ) {
+      context.addIssue({
+        code: "custom",
+        message:
+          "Module route paths must begin with / and must not contain backslashes, " +
+          "percent-encoding, query strings, or fragments.",
+      });
+      return;
+    }
+    if (value === "/") {
+      return;
+    }
+    if (value.endsWith("/")) {
+      context.addIssue({
+        code: "custom",
+        message: "Non-root module route paths must not end with /.",
+      });
+      return;
+    }
+
+    const segments = value.slice(1).split("/");
+    const parameterNames = new Set<string>();
+    for (const segment of segments) {
+      const isParameter = segment.startsWith(":");
+      const matchesGrammar = isParameter
+        ? parameterSegmentPattern.test(segment)
+        : staticSegmentPattern.test(segment);
+      if (!matchesGrammar) {
+        context.addIssue({
+          code: "custom",
+          message:
+            "Module route path segments must be lowercase kebab-case static segments or a " +
+            "single :parameterName segment.",
+        });
+        return;
+      }
+      if (isParameter) {
+        const parameterName = segment.slice(1);
+        if (parameterNames.has(parameterName)) {
+          context.addIssue({
+            code: "custom",
+            message: "Module route path parameter names must be unique within the path.",
+          });
+          return;
+        }
+        parameterNames.add(parameterName);
+      }
+    }
+  });
+
+export type ModuleRoutePath = z.output<typeof moduleRoutePathSchema>;
+
+export function parseModuleRoutePath(input: unknown): ModuleRoutePath {
+  return moduleRoutePathSchema.parse(input);
+}
+
+export function safeParseModuleRoutePath(input: unknown): z.ZodSafeParseResult<ModuleRoutePath> {
+  return moduleRoutePathSchema.safeParse(input);
+}
+
+/**
+ * Produces a deterministic key identifying a route's shape — method plus path with every parameter
+ * segment collapsed to one placeholder — so `/events/:eventId` and `/events/:id` collide under the
+ * same method exactly like the identical route they are, regardless of the parameter's chosen name.
+ * Takes an already-validated `ModuleRoutePath`; never re-validates or echoes the original path.
+ */
+export function moduleRouteShapeKey(method: ModuleHttpMethod, path: ModuleRoutePath): string {
+  if (path === "/") {
+    return `${method} /`;
+  }
+  const shapeSegments = path
+    .slice(1)
+    .split("/")
+    .map((segment) => (segment.startsWith(":") ? ":param" : segment));
+  return `${method} /${shapeSegments.join("/")}`;
+}
+
+/**
+ * What a module's route handler receives about the caller and the match — never a database
+ * connection, authorization-store, grant-management, storage, jobs, configuration, secrets, the
+ * Hono `Context`, or a raw Better Auth session. `principal` is already authorized by the time a
+ * handler runs: `apps/api/src/module-http-routes.ts` mounts and enforces every route before ever
+ * invoking its handler; this contracts-layer module never invokes a handler itself.
+ */
+export interface ModuleRouteHandlerContext {
+  readonly moduleId: ModuleId;
+  readonly principal: EkklesiaPrincipal;
+  readonly params: Readonly<Record<string, string>>;
+}
+
+/** A framework-neutral Fetch handler: standard `Request` in, standard `Response` out. The full
+ * query string remains available through `Request.url`; there is no competing query or body
+ * abstraction. */
+export type ModuleRouteHandler = (
+  request: Request,
+  context: ModuleRouteHandlerContext,
+) => Awaitable<Response>;
+
+/**
+ * What a module passes to `http.route(...)` during `register`. `permission` is a plain string here
+ * (never the branded `PermissionId`) so a module can write a literal permission id without an
+ * explicit parse call first; `http.route` validates and brands it. The type has exactly these four
+ * fields — a module cannot specify a baseline, mount prefix, absolute path, CORS/origin policy,
+ * authentication behavior, grant/platform-owner state, middleware, audit metadata, another module's
+ * namespace, or an unprotected/no-permission route.
+ */
+export interface ModuleRouteDefinitionInput {
+  readonly method: ModuleHttpMethod;
+  readonly path: string;
+  readonly permission: string;
+  readonly handler: ModuleRouteHandler;
+}
+
+/** The validated, canonical form of a `ModuleRouteDefinitionInput` — what `http.route` produces
+ * only after every field passes its own grammar. */
+export interface ModuleRouteDefinition {
+  readonly method: ModuleHttpMethod;
+  readonly path: ModuleRoutePath;
+  readonly permission: PermissionId;
+  readonly handler: ModuleRouteHandler;
+}
+
+/** The Fetch-based registrar exposed as `context.http` during `register` only — never on
+ * `ModuleRuntimeContext`, so `start`/`stop` cannot register a route after the fact. */
+export interface ModuleHttpRouteRegistrar {
+  route(definition: ModuleRouteDefinitionInput): void;
+}
+
+/** One published route in `StartedModuleRuntime`'s immutable route snapshot — the same validated
+ * fields as `ModuleRouteDefinition` plus the owning module's ID, which the production mount prefix
+ * (`/api/v1/modules/<module-id>`, `apps/api/src/module-http-routes.ts`) uses to keep two modules'
+ * routes from ever colliding regardless of their own local paths. */
+export interface RegisteredModuleHttpRoute {
+  readonly moduleId: ModuleId;
+  readonly method: ModuleHttpMethod;
+  readonly path: ModuleRoutePath;
+  readonly permission: PermissionId;
+  readonly handler: ModuleRouteHandler;
+}
+
+const moduleRouteDefinitionKeys = new Set(["method", "path", "permission", "handler"]);
+
+function isRecord(value: unknown): value is Record<string, unknown> {
+  return typeof value === "object" && value !== null && !Array.isArray(value);
+}
+
+function hasModuleRouteDefinitionShape(
+  value: unknown,
+): value is { method: unknown; path: unknown; permission: unknown; handler: unknown } {
+  if (!isRecord(value)) {
+    return false;
+  }
+  const keys = Object.keys(value);
+  return (
+    keys.length === moduleRouteDefinitionKeys.size &&
+    keys.every((key) => moduleRouteDefinitionKeys.has(key)) &&
+    typeof value.handler === "function"
+  );
+}
+
+export type ModuleRouteDefinitionIssueCode =
+  | "MODULE_ROUTE_DEFINITION_INVALID"
+  | "MODULE_ROUTE_METHOD_INVALID"
+  | "MODULE_ROUTE_PATH_INVALID"
+  | "MODULE_ROUTE_PERMISSION_INVALID";
+
+export type ModuleRouteDefinitionParseResult =
+  | { readonly success: true; readonly data: ModuleRouteDefinition }
+  | { readonly success: false; readonly code: ModuleRouteDefinitionIssueCode };
+
+/**
+ * Validates every field-level rule a route definition must satisfy on its own — exact shape,
+ * canonical method, canonical path, well-formed permission id — but never whether the permission is
+ * actually declared by the registering module. That ownership check needs the module's own manifest
+ * and belongs to the caller (Core's module runtime), not this framework-neutral contract. Never
+ * echoes the rejected input in the returned code.
+ */
+export function safeParseModuleRouteDefinition(value: unknown): ModuleRouteDefinitionParseResult {
+  if (!hasModuleRouteDefinitionShape(value)) {
+    return { success: false, code: "MODULE_ROUTE_DEFINITION_INVALID" };
+  }
+  if (!isModuleHttpMethod(value.method)) {
+    return { success: false, code: "MODULE_ROUTE_METHOD_INVALID" };
+  }
+  const parsedPath = moduleRoutePathSchema.safeParse(value.path);
+  if (!parsedPath.success) {
+    return { success: false, code: "MODULE_ROUTE_PATH_INVALID" };
+  }
+  const parsedPermission = permissionIdSchema.safeParse(value.permission);
+  if (!parsedPermission.success) {
+    return { success: false, code: "MODULE_ROUTE_PERMISSION_INVALID" };
+  }
+  return {
+    success: true,
+    data: Object.freeze({
+      method: value.method,
+      path: parsedPath.data,
+      permission: parsedPermission.data,
+      handler: value.handler as ModuleRouteHandler,
+    }),
+  };
+}
+
+export function parseModuleRouteDefinition(value: unknown): ModuleRouteDefinition {
+  const result = safeParseModuleRouteDefinition(value);
+  if (!result.success) {
+    throw new TypeError("Invalid Ekklesia module route definition.");
+  }
+  return result.data;
+}
@@ -1,5 +1,6 @@
 import type { CapabilityId, ModuleId } from "./identifiers.js";
 import { moduleIdSchema } from "./identifiers.js";
+import type { ModuleHttpRouteRegistrar } from "./module-http.js";
 import { semanticVersionSchema } from "./versions.js";

 export type Awaitable<Value> = Value | PromiseLike<Value>;
@@ -21,6 +22,10 @@ export interface CapabilityRegistrar extends CapabilityResolver {

 export interface ModuleRegistrationContext {
  readonly capabilities: CapabilityRegistrar;
+  /** Available only during `register` — never on `ModuleRuntimeContext` — so a route can only ever
+   * be declared while Core is still building the immutable startup snapshot, never added or removed
+   * afterward from `start`, `stop`, or any other post-registration code path. */
+  readonly http: ModuleHttpRouteRegistrar;
  readonly moduleId: ModuleId;
 }

@@ -0,0 +1,255 @@
+import { describe, expect, it } from "vitest";
+import {
+  isModuleHttpMethod,
+  MODULE_HTTP_METHODS,
+  type ModuleRouteDefinitionInput,
+  moduleRoutePathSchema,
+  moduleRouteShapeKey,
+  parseModuleRouteDefinition,
+  parseModuleRoutePath,
+  safeParseModuleRouteDefinition,
+  safeParseModuleRoutePath,
+} from "../src/index.js";
+
+function noopHandler(): Response {
+  return new Response(null, { status: 204 });
+}
+
+function validDefinition(
+  overrides: Partial<ModuleRouteDefinitionInput> = {},
+): ModuleRouteDefinitionInput {
+  return {
+    method: "GET",
+    path: "/events/:eventId",
+    permission: "calendar.events.read",
+    handler: noopHandler,
+    ...overrides,
+  };
+}
+
+describe("ModuleHttpMethod", () => {
+  it("accepts every supported method", () => {
+    for (const method of MODULE_HTTP_METHODS) {
+      expect(isModuleHttpMethod(method)).toBe(true);
+    }
+    expect(MODULE_HTTP_METHODS).toEqual(["DELETE", "GET", "PATCH", "POST", "PUT"]);
+  });
+
+  it("rejects lowercase, unknown, OPTIONS, HEAD, and wildcard methods", () => {
+    for (const method of ["get", "post", "TRACE", "OPTIONS", "HEAD", "*", "ALL", ""]) {
+      expect(isModuleHttpMethod(method)).toBe(false);
+    }
+    expect(isModuleHttpMethod(42)).toBe(false);
+    expect(isModuleHttpMethod(undefined)).toBe(false);
+  });
+});
+
+describe("moduleRoutePathSchema", () => {
+  it("accepts the root, static, nested, and parameterized canonical paths", () => {
+    for (const path of [
+      "/",
+      "/events",
+      "/events/upcoming",
+      "/events/:eventId",
+      "/events/:eventId/attendees/:attendeeId",
+    ]) {
+      expect(parseModuleRoutePath(path)).toBe(path);
+    }
+  });
+
+  it("rejects paths that do not begin with /", () => {
+    expect(safeParseModuleRoutePath("events").success).toBe(false);
+    expect(safeParseModuleRoutePath("").success).toBe(false);
+  });
+
+  it("rejects a non-root path ending with /", () => {
+    expect(safeParseModuleRoutePath("/events/").success).toBe(false);
+  });
+
+  it("rejects empty and repeated segments", () => {
+    expect(safeParseModuleRoutePath("/events//upcoming").success).toBe(false);
+    expect(safeParseModuleRoutePath("//events").success).toBe(false);
+  });
+
+  it("rejects query strings and fragments", () => {
+    expect(safeParseModuleRoutePath("/events?limit=10").success).toBe(false);
+    expect(safeParseModuleRoutePath("/events#upcoming").success).toBe(false);
+  });
+
+  it("rejects backslashes and percent-encoded path syntax", () => {
+    expect(safeParseModuleRoutePath("/events\\upcoming").success).toBe(false);
+    expect(safeParseModuleRoutePath("/events%2Fupcoming").success).toBe(false);
+    expect(safeParseModuleRoutePath("/%2e%2e/events").success).toBe(false);
+  });
+
+  it("rejects dot segments and traversal syntax", () => {
+    expect(safeParseModuleRoutePath("/events/..").success).toBe(false);
+    expect(safeParseModuleRoutePath("/events/.").success).toBe(false);
+    expect(safeParseModuleRoutePath("/../events").success).toBe(false);
+  });
+
+  it("rejects wildcard or catch-all segments", () => {
+    expect(safeParseModuleRoutePath("/events/*").success).toBe(false);
+    expect(safeParseModuleRoutePath("/events/**").success).toBe(false);
+    expect(safeParseModuleRoutePath("/*").success).toBe(false);
+  });
+
+  it("rejects non-kebab-case static segments", () => {
+    expect(safeParseModuleRoutePath("/Events").success).toBe(false);
+    expect(safeParseModuleRoutePath("/events_list").success).toBe(false);
+    expect(safeParseModuleRoutePath("/events--upcoming").success).toBe(false);
+    expect(safeParseModuleRoutePath("/-events").success).toBe(false);
+    expect(safeParseModuleRoutePath("/events-").success).toBe(false);
+  });
+
+  it("rejects a malformed parameter segment", () => {
+    expect(safeParseModuleRoutePath("/events/:").success).toBe(false);
+    expect(safeParseModuleRoutePath("/events/:Event-Id").success).toBe(false);
+    expect(safeParseModuleRoutePath("/events/:1id").success).toBe(false);
+  });
+
+  it("rejects duplicate parameter names within one path", () => {
+    expect(safeParseModuleRoutePath("/events/:id/attendees/:id").success).toBe(false);
+  });
+
+  it("rejects an unreasonably long path", () => {
+    expect(safeParseModuleRoutePath(`/${"a".repeat(300)}`).success).toBe(false);
+  });
+
+  it("never echoes the rejected raw path in its issue messages", () => {
+    const secret = "/machine/private/path/traversal-attempt-%2e%2e";
+    const result = moduleRoutePathSchema.safeParse(secret);
+    expect(result.success).toBe(false);
+    expect(JSON.stringify(result.error?.issues)).not.toContain(secret);
+  });
+});
+
+describe("moduleRouteShapeKey", () => {
+  it("collapses different parameter names into the same shape for the same method", () => {
+    const eventId = parseModuleRoutePath("/events/:eventId");
+    const id = parseModuleRoutePath("/events/:id");
+    expect(moduleRouteShapeKey("GET", eventId)).toBe(moduleRouteShapeKey("GET", id));
+  });
+
+  it("distinguishes shapes by method and by static path structure", () => {
+    const path = parseModuleRoutePath("/events/:eventId");
+    expect(moduleRouteShapeKey("GET", path)).not.toBe(moduleRouteShapeKey("POST", path));
+    expect(moduleRouteShapeKey("GET", parseModuleRoutePath("/events"))).not.toBe(
+      moduleRouteShapeKey("GET", parseModuleRoutePath("/events/:eventId")),
+    );
+  });
+
+  it("treats the root path as its own shape", () => {
+    expect(moduleRouteShapeKey("GET", parseModuleRoutePath("/"))).toBe("GET /");
+  });
+});
+
+describe("safeParseModuleRouteDefinition", () => {
+  it("accepts a well-formed definition and brands its path and permission", () => {
+    const result = safeParseModuleRouteDefinition(validDefinition());
+    expect(result.success).toBe(true);
+    if (result.success) {
+      expect(result.data).toEqual({
+        method: "GET",
+        path: "/events/:eventId",
+        permission: "calendar.events.read",
+        handler: noopHandler,
+      });
+      expect(Object.isFrozen(result.data)).toBe(true);
+    }
+  });
+
+  it("rejects a non-object, null, or array definition", () => {
+    for (const value of [null, undefined, "route", 42, []]) {
+      expect(safeParseModuleRouteDefinition(value)).toEqual({
+        success: false,
+        code: "MODULE_ROUTE_DEFINITION_INVALID",
+      });
+    }
+  });
+
+  it("rejects an unknown route-definition field", () => {
+    expect(safeParseModuleRouteDefinition({ ...validDefinition(), baseline: "public" })).toEqual({
+      success: false,
+      code: "MODULE_ROUTE_DEFINITION_INVALID",
+    });
+    expect(
+      safeParseModuleRouteDefinition({ ...validDefinition(), mountPrefix: "/custom" }),
+    ).toEqual({ success: false, code: "MODULE_ROUTE_DEFINITION_INVALID" });
+  });
+
+  it("rejects a missing required field", () => {
+    const { handler: _handler, ...withoutHandler } = validDefinition();
+    expect(safeParseModuleRouteDefinition(withoutHandler)).toEqual({
+      success: false,
+      code: "MODULE_ROUTE_DEFINITION_INVALID",
+    });
+  });
+
+  it("rejects a non-function handler", () => {
+    expect(
+      safeParseModuleRouteDefinition({ ...validDefinition(), handler: "not-a-function" }),
+    ).toEqual({ success: false, code: "MODULE_ROUTE_DEFINITION_INVALID" });
+  });
+
+  it("rejects an invalid method", () => {
+    expect(safeParseModuleRouteDefinition({ ...validDefinition(), method: "get" })).toEqual({
+      success: false,
+      code: "MODULE_ROUTE_METHOD_INVALID",
+    });
+  });
+
+  it("rejects an invalid path", () => {
+    expect(safeParseModuleRouteDefinition({ ...validDefinition(), path: "events" })).toEqual({
+      success: false,
+      code: "MODULE_ROUTE_PATH_INVALID",
+    });
+  });
+
+  it("rejects an invalid permission id", () => {
+    expect(
+      safeParseModuleRouteDefinition({ ...validDefinition(), permission: "not namespaced" }),
+    ).toEqual({ success: false, code: "MODULE_ROUTE_PERMISSION_INVALID" });
+    expect(safeParseModuleRouteDefinition({ ...validDefinition(), permission: "*" })).toEqual({
+      success: false,
+      code: "MODULE_ROUTE_PERMISSION_INVALID",
+    });
+  });
+
+  it("does not retain the caller's mutable definition object: mutating it afterward cannot change the parsed result", () => {
+    const source = { ...validDefinition() };
+    const result = safeParseModuleRouteDefinition(source);
+    expect(result.success).toBe(true);
+    source.method = "POST";
+    source.path = "/mutated";
+    source.permission = "mutated.permission.id";
+    if (result.success) {
+      expect(result.data.method).toBe("GET");
+      expect(result.data.path).toBe("/events/:eventId");
+      expect(result.data.permission).toBe("calendar.events.read");
+    }
+  });
+});
+
+describe("parseModuleRouteDefinition", () => {
+  it("returns the parsed definition for valid input", () => {
+    expect(parseModuleRouteDefinition(validDefinition())).toMatchObject({
+      method: "GET",
+      path: "/events/:eventId",
+      permission: "calendar.events.read",
+    });
+  });
+
+  it("throws without echoing the rejected input", () => {
+    const secret = "secret-token-value";
+    expect(() => parseModuleRouteDefinition({ ...validDefinition(), permission: secret })).toThrow(
+      "Invalid Ekklesia module route definition.",
+    );
+    try {
+      parseModuleRouteDefinition({ ...validDefinition(), permission: secret });
+      throw new Error("expected parseModuleRouteDefinition to throw");
+    } catch (error) {
+      expect(String(error)).not.toContain(secret);
+    }
+  });
+});
@@ -1,5 +1,11 @@
 import { describe, expect, it, vi } from "vitest";
-import { defineModuleRuntime } from "../src/index.js";
+import {
+  defineModuleRuntime,
+  isModuleHttpMethod,
+  MODULE_HTTP_METHODS,
+  type ModuleHttpRouteRegistrar,
+  type ModuleRegistrationContext,
+} from "../src/index.js";

 describe("defineModuleRuntime", () => {
  it("defines a frozen server runtime without duplicating the static manifest", async () => {
@@ -22,4 +28,42 @@ describe("defineModuleRuntime", () => {
      }),
    ).toThrow("Invalid Ekklesia module runtime definition.");
  });
+
+  it("re-exports the module-http contract so a module's register hook can declare routes", async () => {
+    expect(MODULE_HTTP_METHODS).toContain("GET");
+    expect(isModuleHttpMethod("GET")).toBe(true);
+    expect(isModuleHttpMethod("get")).toBe(false);
+
+    const registeredRoutes: unknown[] = [];
+    const http: ModuleHttpRouteRegistrar = {
+      route: (definition) => {
+        registeredRoutes.push(definition);
+      },
+    };
+    const runtime = defineModuleRuntime({
+      id: "example",
+      version: "0.1.0",
+      register({ http: registrar }) {
+        registrar.route({
+          method: "GET",
+          path: "/records",
+          permission: "example.records.read",
+          handler: () => new Response(null, { status: 204 }),
+        });
+      },
+    });
+
+    const context: ModuleRegistrationContext = {
+      capabilities: {
+        provide: () => undefined,
+        resolve: () => undefined,
+      },
+      http,
+      moduleId: "example",
+    };
+    await runtime.register?.(context);
+
+    expect(registeredRoutes).toHaveLength(1);
+    expect(registeredRoutes[0]).toMatchObject({ method: "GET", path: "/records" });
+  });
 });
@@ -70,6 +70,11 @@ describe("module template", () => {
          return undefined;
        },
      },
+      http: {
+        route() {
+          throw new Error("The template does not register any HTTP route.");
+        },
+      },
      moduleId: "example",
    });