Rate Limiting

Sliding window limiter for Next.js API routes

Production rate limiting with in-memory sliding window (works on Vercel, single Lambda) and optional Upstash Redis for multi-instance production. Per-endpoint configs, X-RateLimit headers, 429 responses with Retry-After, withRateLimit() and withAuthRateLimit() wrappers, and a peek function for dashboard display.

1var(--text-3);font-style:italic">// Protect an API route:
2export const POST = withRateLimit('auth', async (req) => {
3  return NextResponse.json({ ok: true })
4})
5var(--text-3);font-style:italic">// Automatic 429 + Retry-After on breach. X-RateLimit-* headers on all responses.