Clerk + Next.js middleware
Protect routes with Clerk's middleware in Next.js App Router.
Snippets
Code snippet library
Ready TS/Python boilerplate for auth, AI, web, data, web3, ops. Copy, paste, ask the AI to extend.
29 entries
Auth & session
5 entriesLucia session check (App Router)
Server-side session lookup with Lucia in a server component.
Verify a JWT (jose)
Verify an HS256/RS256 JWT and extract claims with jose.
Auth.js credentials provider
Email + password sign-in with Auth.js (NextAuth) v5.
Verify a webhook signature (HMAC-SHA256)
Constant-time HMAC verification for incoming webhooks.
AI & LLM
8 entriesClaude streaming chat
Stream tokens from Claude Sonnet 4.6 via the official SDK.
Claude tool use loop
Minimal loop: model picks a tool, you run it, feed the result back.
Anthropic prompt caching
Mark a long system prompt as cacheable to cut token cost on repeated calls.
OpenAI streaming completion
Stream a chat completion from GPT-4o with the official SDK.
Batch embeddings (OpenAI)
Embed many texts in one call. Cheaper + faster than one-at-a-time.
Tiny RAG retrieve (cosine)
Brute-force cosine search over an in-memory vector store. Works for ≤10k chunks.
Vercel AI SDK tool calling
Define a typed tool with Zod and let the model invoke it through generateText.
Strict JSON output (Anthropic)
Coerce the model to return parseable JSON. Wrap with jsonrepair fallback.
Web & frontend
6 entriesfetch with timeout + retry
Cancel slow requests, retry transient 5xx with exponential backoff.
useDebounce hook
Delay a value update until N ms after the last change. For search-as-you-type.
useInView hook (IntersectionObserver)
Trigger when an element enters the viewport. Lazy load + infinite scroll.
Server Action form (Next.js)
Form posts directly to a server function. No client state library.
Edge rate limit (Upstash)
Per-IP fixed window rate limit at the edge.
Presigned S3 upload URL
Server signs, browser PUTs directly to S3 — no payload through your server.
DB & cache
4 entriesDrizzle schema + relations
Typed Postgres schema with one-to-many relation. Drives migrations.
Prisma interactive transaction
Multi-step write that rolls back on any error.
Postgres advisory lock
App-level lock keyed by an int, useful for preventing duplicate cron runs.
Cache wrapper (read-through)
Wrap any async function to memoize its result in Redis with TTL.