diff --git a/packages/auth/src/di/bind-production.ts b/packages/auth/src/di/bind-production.ts
index 94d5868..b422fb0 100644
--- a/packages/auth/src/di/bind-production.ts
+++ b/packages/auth/src/di/bind-production.ts
@@ -6,7 +6,9 @@ import {
   type ILogger,
 } from "@repo/core-shared/instrumentation";
 import type { BindProductionContext } from "@repo/core-shared/di";
+import { assertFeatureConformance } from "@repo/core-shared/conformance";
 import type { ProductionUseCase } from "@repo/core-shared/conformance";
+import { authManifest } from "../feature.manifest";
 import type { AuthManifest } from "../feature.manifest";
 import type {
   SignInInput,
@@ -158,4 +160,17 @@ export function bindProductionAuth(ctx: BindProductionContext): void {
   // <gen:event-handlers>
   // <gen:jobs>
   // <gen:realtime-handlers>
+
+  // Boot-time conformance check: refuses to start if any use-case binding
+  // is missing a required brand (withSpan / withCapture / withAudit).
+  assertFeatureConformance(
+    authContainer,
+    authManifest,
+    {
+      signIn: AUTH_SYMBOLS.ISignInUseCase,
+      signUp: AUTH_SYMBOLS.ISignUpUseCase,
+      signOut: AUTH_SYMBOLS.ISignOutUseCase,
+    },
+    ctx,
+  );
 }