VibeCoder Vault vs. Cursor AI Prompts

Select code → Cmd+K → "refactor this to use hooks"

You are a senior React engineer specializing in performance optimization.

Refactor this component:
- Component: [PASTE CODE]
- Current issues: [prop drilling / re-renders / mixed concerns]
- Target patterns: custom hooks, React.memo, useCallback where needed

Requirements:
1. Extract business logic into a custom hook
2. Memoize expensive computations
3. Split into presentational + container if over 150 lines
4. Add TypeScript strict types for all props
5. Preserve existing test contracts

Cmd+K → "create a POST endpoint for user registration"

You are a backend security engineer building production APIs.

Create a POST /api/users/register endpoint:
- Framework: [Next.js API route / Express / Fastify]
- Database: [PostgreSQL via Prisma / Drizzle]
- Auth: [bcrypt + JWT / Auth.js]

Generate:
1. Input validation with Zod schema (email, password strength, username)
2. Rate limiting (5 attempts per IP per minute)
3. Password hashing with bcrypt (12 rounds)
4. Duplicate email check with timing-safe comparison
5. JWT token generation with appropriate expiry
6. Error responses following RFC 7807 Problem Details
7. Request logging (sanitized — no passwords in logs)

Select slow code → "why is this slow and how do I fix it?"

You are a performance optimization specialist.

Diagnose and fix this performance bottleneck:
- Code: [PASTE SLOW CODE]
- Environment: [React / Node.js / database query]
- Observed behavior: [page loads in 3s, should be <500ms]
- Data scale: [~10K rows / ~1M records]

Provide:
1. Root cause analysis with Big-O complexity
2. Profiling strategy (which metrics to measure)
3. Fix with before/after code
4. Performance benchmark expectations
5. Monitoring query to detect future regressions