Hey folks! 👋 Today, I want to share 7 common mistakes that many NodeJS developers make. I’ve been working with NodeJS since 2012, and trust me, I’ve made plenty of mistakes. 😅 But that’s how we learn! So, let’s go through these mistakes and how to avoid them.
This post is a written version of my Youtube video about this topic.
Misunderstanding Async/Await
Many developers use await on every line, not realizing that this makes each task run one after another. If the tasks don’t depend on each other, you should run them in parallel using Promise.all() or Promise.allSettled(). This way, you avoid unnecessary delays and improve performance.
Poor Error Handling
A lot of developers focus only on the “happy path” and forget that things can go wrong: network failures, database timeouts, or unexpected inputs. Always catch errors, log them, and handle them properly so your app doesn’t crash unexpectedly.
No Scalability Planning
When writing code, think ahead. What happens if 1 million users request the same endpoint at once? What if a database query returns a huge number of rows? Consider caching, load balancing, queues, and making your app stateless so it can scale horizontally.
Blocking the Event Loop
Node.js is single-threaded, so CPU-heavy tasks can block the event loop, making the app slow. If you need to process large files or perform heavy computations, use streams or move the task to a worker thread or queue system.
Poor Code Organization
Building an app is one thing, but maintaining and scaling it over time is another. Writing clean code and using a solid architecture is crucial. Otherwise, you’ll struggle in the future (like I did 😅). Invest time in organizing your code properly!
No Testing
You don’t need 100% test coverage, but at least cover the core functionality. Tests save you from breaking things when updating dependencies or adding new features. Some say, “We don’t have time for tests.” But in reality, skipping tests leads to more wasted time fixing unexpected issues.
Ignoring Security
Security is not optional! Always use authentication, encrypt sensitive data, hash passwords, enable firewalls, and never hardcode credentials. Use environment variables instead. A security checklist can help you stay on track and avoid common vulnerabilities.
These are just some of the mistakes I’ve seen (and made myself). Hopefully, this helps you avoid them!
🚀 Have you faced any of these issues? Let me know in the comments 😊
