backend-development

# Backend Development ## API Design ### RESTful Conventions ``` GET /users # List users POST /users # Create user GET /users/:id # Get user PUT /users/:id # Update user (full) PATCH /users/:id # Update user (partial) DELETE /users/:id # Delete user GET /users/:id/posts # List user's posts POST /users/:id/posts # Create post for user ``` ### Response Format ```json { "data": { ... }, "meta": { "page": 1, "per_page": 20, "total": 100 } } ``` ### Error Format ```json { "error": { "code": "VALIDATION_ERROR", "message": "Invalid input", "details": [ { "field": "email", "message": "Invalid format" } ] } } ``` ## Database Patterns ### Schema Design ```sql -- Use UUIDs for public IDs CREATE TABLE users ( id SERIAL PRIMARY KEY, public_id UUID DEFAULT gen_random_uuid() UNIQUE, email VARCHAR(255) UNIQUE NOT NULL, created_at TIMESTAMPTZ DEFAULT NOW(), updated_at TIMESTAMPTZ DEFAULT NOW() ); -- Soft deletes ALTER TABLE users ADD COLUMN deleted_at TIMESTAMPTZ; -- Indexes CREATE INDEX idx_users_email ON users(email); CREATE INDEX idx_users_created ON users(created_at DESC); ``` ### Query Patterns ```sql -- Pagination with cursor SELECT * FROM posts WHERE created_at < $cursor ORDER BY created_at DESC LIMIT 20; -- Efficient counting SELECT reltuples::bigint AS estimate FROM pg_class WHERE relname = 'users'; ``` ## Authentication ### JWT Pattern ```typescript interface To...