vercel-local-dev-loop

# Vercel Local Dev Loop ## Overview Run Vercel serverless functions and API routes locally using `vercel dev`. Covers environment variable management, hot reload, local testing patterns, and framework-specific dev servers. ## Prerequisites - Completed `vercel-install-auth` setup - Project linked via `vercel link` - Node.js 18+ with npm/pnpm ## Instructions ### Step 1: Pull Environment Variables ```bash # Pull env vars from Vercel to local .env files vercel env pull .env.development.local # This creates .env.development.local with all Development-scoped vars: # VERCEL="1" # VERCEL_ENV="development" # DATABASE_URL="postgres://..." # API_SECRET="sk-..." ``` ### Step 2: Start Local Dev Server ```bash # vercel dev starts a local server that emulates the Vercel platform vercel dev # Output: # Vercel CLI 39.x.x — dev command # > Ready on http://localhost:3000 # With a specific port vercel dev --listen 8080 # With debug logging vercel dev --debug ``` `vercel dev` provides: - Serverless function emulation at `/api/*` routes - Automatic TypeScript compilation - `vercel.json` rewrites, redirects, and headers applied locally - Environment variables loaded from `.env*.local` files - Framework detection (Next.js, Nuxt, SvelteKit, etc.) ### Step 3: Test Serverless Functions Locally ```bash # Test your API route curl http://localhost:3000/api/hello # {"message":"Hello from Vercel Serverless Function!"} # Test with POST body curl -X POST http://localhost:3000/api/users \ -H "Con...