diff --git a/skills/design-patterns/references/architecture-patterns.md b/skills/design-patterns/references/architecture-patterns.md
index 8c6841b..f98eb6f 100644
--- a/skills/design-patterns/references/architecture-patterns.md
+++ b/skills/design-patterns/references/architecture-patterns.md
@@ -58,10 +58,12 @@ src/
 ```typescript
 // app/api/users/route.ts — Controller (THIN)
 import { UserService } from "@/services/user.service";
+import { CreateUserSchema } from "@/types/user.types";
 
 export async function POST(req: Request) {
   const body = await req.json();
-  const result = await UserService.create(body);
+  const validated = CreateUserSchema.parse(body); // ← validate before passing to service
+  const result = await UserService.create(validated);
   return Response.json(result, { status: 201 });
 }
 
diff --git a/skills/design-patterns/references/code-patterns.md b/skills/design-patterns/references/code-patterns.md
index 4aedf40..b919c68 100644
--- a/skills/design-patterns/references/code-patterns.md
+++ b/skills/design-patterns/references/code-patterns.md
@@ -314,13 +314,19 @@ function withAuth(next: Middleware): Middleware {
   };
 }
 
-function withRateLimit(limit: number, next: Middleware): Middleware {
-  const counts = new Map<string, number>();
+function withRateLimit(limit: number, windowMs: number, next: Middleware): Middleware {
+  const windows = new Map<string, { count: number; resetAt: number }>();
   return async (req) => {
     const ip = req.headers.get("x-forwarded-for") ?? "unknown";
-    const current = counts.get(ip) ?? 0;
-    if (current >= limit) return new Response("Too Many Requests", { status: 429 });
-    counts.set(ip, current + 1);
+    const now = Date.now();
+    const w = windows.get(ip);
+    if (!w || w.resetAt <= now) {
+      windows.set(ip, { count: 1, resetAt: now + windowMs });
+    } else if (w.count >= limit) {
+      return new Response("Too Many Requests", { status: 429 });
+    } else {
+      w.count++;
+    }
     return next(req);
   };
 }
diff --git a/skills/design-patterns/references/framework-catalog.md b/skills/design-patterns/references/framework-catalog.md
index cc78c01..a5ae08c 100644
--- a/skills/design-patterns/references/framework-catalog.md
+++ b/skills/design-patterns/references/framework-catalog.md
@@ -57,10 +57,11 @@ src/
 // app/actions/user.actions.ts
 "use server"
 import { UserService } from "@/services/user.service";
+import { CreateUserSchema } from "@/types/user.types";
 import { revalidatePath } from "next/cache";
 
 export async function createUser(formData: FormData) {
-  const data = Object.fromEntries(formData);
+  const data = CreateUserSchema.parse(Object.fromEntries(formData)); // ← validate first
   await UserService.create(data);
   revalidatePath("/dashboard/users");
 }
diff --git a/skills/design-patterns/references/testing-patterns.md b/skills/design-patterns/references/testing-patterns.md
index 9fe6f13..69c6afd 100644
--- a/skills/design-patterns/references/testing-patterns.md
+++ b/skills/design-patterns/references/testing-patterns.md
@@ -31,7 +31,8 @@ describe("NotificationFactory", () => {
   });
 
   it("throws for unknown type", () => {
-    expect(() => createNotification("pigeon" as any)).toThrow();
+    // @ts-expect-error — testing runtime rejection of an invalid type
+    expect(() => createNotification("pigeon")).toThrow();
   });
 });
 ```
@@ -172,7 +173,7 @@ describe("Middleware Decorators", () => {
   });
 
   it("withRateLimit blocks after limit", async () => {
-    const handler = withRateLimit(2, async () => new Response("OK"));
+    const handler = withRateLimit(2, 60_000, async () => new Response("OK"));
     const req = new Request("http://test.com");
     await handler(req);  // 1
     await handler(req);  // 2