diff --git a/packages/dev-server/package.json b/packages/dev-server/package.json
index 33256894..da910339 100644
--- a/packages/dev-server/package.json
+++ b/packages/dev-server/package.json
@@ -8,6 +8,7 @@
     "./serve-entry": "./src/serve-entry.ts"
   },
   "dependencies": {
+    "@wrnexus/authz": "workspace:*",
     "@wrnexus/core": "workspace:*",
     "@wrnexus/dev-toolbar": "workspace:*",
     "@wrnexus/router": "workspace:*",
diff --git a/packages/dev-server/src/authz-boot.ts b/packages/dev-server/src/authz-boot.ts
new file mode 100644
index 00000000..d22022e7
--- /dev/null
+++ b/packages/dev-server/src/authz-boot.ts
@@ -0,0 +1,31 @@
+import { pathToFileURL } from "node:url";
+import { buildRouter } from "@wrnexus/router";
+import {
+  emptyCatalog,
+  mergeCatalogs,
+  type AuthzCatalog,
+  type AuthzModule,
+  type CatalogSource,
+} from "@wrnexus/authz";
+
+/**
+ * Load and merge every `app/authz/*.ts` declaration. Conflicts throw so a
+ * misconfigured catalog fails the boot rather than silently changing who can
+ * do what. An app with no `app/authz/` directory gets an empty catalog rather
+ * than an error, since not every app uses permissions.
+ */
+export async function loadAppAuthzCatalog(appDir: string): Promise<AuthzCatalog> {
+  const router = buildRouter(appDir);
+  if (!router.authz.length) return emptyCatalog();
+  const sources: CatalogSource[] = [];
+  for (const entry of router.authz) {
+    // buildRouter already skips *.gen.ts, so only real declarations arrive here.
+    const imported = (await import(pathToFileURL(entry.file).href)) as { default?: AuthzModule };
+    if (!imported.default) {
+      console.warn(`[wrnexus] authz declaration ${entry.file} has no default export; skipping.`);
+      continue;
+    }
+    sources.push({ source: entry.file, module: imported.default });
+  }
+  return mergeCatalogs(sources);
+}
diff --git a/packages/dev-server/test/authz-boot.test.ts b/packages/dev-server/test/authz-boot.test.ts
new file mode 100644
index 00000000..52240762
--- /dev/null
+++ b/packages/dev-server/test/authz-boot.test.ts
@@ -0,0 +1,62 @@
+import { afterAll, describe, expect, test } from "bun:test";
+import { mkdirSync, mkdtempSync, rmSync, writeFileSync } from "node:fs";
+import { join } from "node:path";
+import { loadAppAuthzCatalog } from "../src/authz-boot.ts";
+
+// Fixtures must live inside the repo tree, not os.tmpdir(). A scaffolded file
+// under app/authz importing "@wrnexus/authz" by bare specifier resolves via
+// the root tsconfig.json `paths` map, walked from the *imported file's*
+// location — an out-of-tree path (os.tmpdir(), often a different drive on
+// Windows) never reaches it and fails to resolve the module.
+const scratchRoot = join(import.meta.dir, ".tmp-authz-boot");
+mkdirSync(scratchRoot, { recursive: true });
+
+function scaffold(body: string): string {
+  const root = mkdtempSync(join(scratchRoot, "app-"));
+  mkdirSync(join(root, "app", "authz"), { recursive: true });
+  mkdirSync(join(root, "app", "pages"), { recursive: true });
+  writeFileSync(join(root, "app", "authz", "main.ts"), body, "utf8");
+  return join(root, "app");
+}
+
+afterAll(() => {
+  rmSync(scratchRoot, { recursive: true, force: true });
+});
+
+describe("loadAppAuthzCatalog", () => {
+  test("loads declarations from app/authz", async () => {
+    const appDir = scaffold(
+      `import { defineAuthz } from "@wrnexus/authz";
+export default defineAuthz({ permissions: { "post:read": {} } });`,
+    );
+    const catalog = await loadAppAuthzCatalog(appDir);
+    expect(catalog.permissions.has("post:read")).toBe(true);
+  });
+
+  test("an app with no declarations gets an empty catalog rather than an error", async () => {
+    const root = mkdtempSync(join(scratchRoot, "empty-"));
+    mkdirSync(join(root, "app", "pages"), { recursive: true });
+    const catalog = await loadAppAuthzCatalog(join(root, "app"));
+    expect(catalog.permissions.size).toBe(0);
+  });
+
+  test("a conflicting declaration fails the boot loudly", async () => {
+    const appDir = scaffold(
+      `import { defineAuthz } from "@wrnexus/authz";
+export default defineAuthz({ permissions: { "post:read": { risk: "low" } } });`,
+    );
+    writeFileSync(
+      join(appDir, "authz", "other.ts"),
+      `import { defineAuthz } from "@wrnexus/authz";
+export default defineAuthz({ permissions: { "post:read": { risk: "high" } } });`,
+      "utf8",
+    );
+    await expect(loadAppAuthzCatalog(appDir)).rejects.toThrow(/WRN-AUTHZ-CONFLICT/);
+  });
+
+  test("a declaration with no default export is skipped, not fatal", async () => {
+    const appDir = scaffold(`export const notDefault = 1;`);
+    const catalog = await loadAppAuthzCatalog(appDir);
+    expect(catalog.permissions.size).toBe(0);
+  });
+});