Node.js Developer Resume Keywords

What You Need to Know

Node.js developers embrace JavaScript on the backend but face challenges unique to server environments. Async/await syntax makes asynchronous code readable, but you need to understand promises and error handling. Callback hell was solved by promises years ago, but unhandled promise rejections still crash applications if not caught properly. The event loop is Node.js's superpower and its biggest complexity—blocking it with CPU-intensive operations kills performance for all concurrent requests. Memory leaks happen easily when event listeners aren't removed, slowly degrading performance until restart. NPM package security is a constant concern with thousands of dependencies creating a massive attack surface. Supply chain attacks through compromised packages are real threats requiring vigilance. Node.js brought JavaScript to the backend, enabling full-stack JavaScript development. This unified language across frontend and backend appeals to many developers, enabling code sharing and knowledge transfer. But backend development introduces concerns that don't exist in browser code—security vulnerabilities, database management, API design, and production deployment. Understanding these backend-specific concerns is essential for professional Node.js development, not just knowing JavaScript syntax. Express.js remains the most popular Node.js web framework despite newer alternatives. Its minimalist approach provides routing, middleware, and template rendering without imposing structure. But this flexibility means making many decisions yourself. Middleware order matters because each middleware can modify request and response or end the request early. Error handling requires specific middleware patterns—error handlers need four parameters to be recognized. Route organization affects maintainability as applications grow. Understanding Express middleware is fundamental—requests flow through middleware functions sequentially, each capable of modifying data, calling the next middleware, or ending the request. Custom middleware handles cross-cutting concerns like authentication, logging, and request validation. NestJS provides an opinionated, TypeScript-first framework inspired by Angular. Its module system organizes code, dependency injection manages dependencies, and decorators provide declarative syntax. This structure helps in large applications where organization becomes critical. Guards handle authorization, interceptors transform responses, and pipes validate input. But Nest's learning curve is steeper than Express, and its abstraction can obscure what's happening. Understanding when Nest's structure benefits your project versus when Express simplicity suffices requires evaluating project complexity and team preferences. Fastify offers better performance than Express while maintaining API simplicity. Schema-based validation provides automatic request validation and response serialization, catching errors early. Plugin architecture enables extending functionality. Asynchronous programming is fundamental to Node.js but creates pitfalls. Every I/O operation—database queries, file operations, HTTP requests—is asynchronous by default. Using async/await makes code look synchronous, greatly improving readability. But error handling with async functions requires try-catch blocks or .catch() on promises. Unhandled promise rejections crash applications in modern Node.js versions. Understanding the event loop—how microtasks, timers, I/O callbacks, and close callbacks are scheduled—helps debug unexpected behavior and performance issues. Database access patterns differ from traditional blocking I/O. ORMs like Prisma generate type-safe database clients, catching errors at compile time through TypeScript integration. Prisma migrations manage schema changes. TypeORM provides Active Record and Data Mapper patterns, each with different trade-offs around simplicity and separation of concerns. Sequelize is older but widely used, providing promise-based operations and migrations. Understanding N+1 query problems, database transactions, and connection pooling is essential for performance. Raw SQL queries with libraries like node-postgres provide maximum control but require careful parameter sanitization to prevent SQL injection. Query builders like Knex.js provide a middle ground between raw SQL and full ORMs. Authentication and authorization are common backend responsibilities. JWT tokens provide stateless authentication, embedding user information in the token itself. But token expiration, refresh token rotation, and token revocation require careful design. Session-based authentication stores state on the server in session stores like Redis, requiring session management but enabling easy revocation. Passport.js provides strategies for various authentication methods—local username/password, OAuth for social login, SAML for enterprise SSO. Understanding security concerns is non-negotiable—password hashing with bcrypt, rate limiting to prevent brute force attacks, CSRF protection for state-changing operations, and proper CORS configuration. Real-time features use WebSockets or Socket.io for bidirectional communication. Building chat applications, live notifications, or collaborative editing requires understanding WebSocket connections, rooms for grouping connections, and namespaces for separation. Socket.io adds reconnection logic, fallback transports, and convenience methods over raw WebSockets. But WebSocket connections are stateful, complicating horizontal scaling and load balancing. Sticky sessions ensure connections route to the same server, but better approaches use Redis adapters for message passing between servers. Error handling in Node.js requires discipline because errors in asynchronous code don't propagate automatically. Async errors need explicit catching with try-catch or promise rejection handlers. Centralized error handling with Express error middleware provides consistent error responses. Logging errors with Winston, Pino, or Bunyan helps debug production issues, providing structured logging with different log levels. Understanding when to crash the process versus recovering from errors affects application reliability. Microservices architecture is common in Node.js applications. Multiple small services communicate via HTTP APIs or message queues. This architecture enables independent deployment, scaling, and technology choices. But microservices introduce complexity—service discovery, inter-service authentication, distributed tracing, and eventual consistency. Message queues like RabbitMQ or Kafka handle asynchronous communication between services. Docker containerizes services for consistent deployment across environments.