How to Hire Express.js Developers and Fix Slow Backends

Hiring Express.js developers sounds simple — after all, it’s the fifth most popular framework according to the 2024 Stack Overflow Developer Survey. But then reality hits. You bring someone on board, and suddenly, your backend starts lagging. APIs slow down, users drop off, and performance issues arise.

You thought you made a solid hire, but now you’re here, dealing with bottlenecks. Express.js is powerful, yet in the wrong hands, it can become a nightmare. If that sounds familiar, this guide is for you. We’ll explain how to hire the right Express.js developers and maintain a fast, stable, and scalable backend.

What Slows Down Express.js Backends and Why Most Developers Miss It

Engineers love Express.js for its simplicity. It’s minimal, unopinionated, and gets your project up and running fast. Yet, that is a double-edged sword.

Since Express.js doesn’t enforce structure, performance practices, or scalability patterns by default, it’s easy for less experienced Express.js developers to build apps that work fine—until they don’t.

Once real users start accessing your API, problems come up: slow response times, sudden server loads, or unpredictable crashes. The backend looks good on the surface, but it isn’t under the hood.

Let’s now look at the most common technical causes of performance bottlenecks in Express.js projects:

• Inefficient routing or middleware stacking. Poorly organized routing logic or stacking all middleware at the top level can slow down every request. If you have too many unnecessary checkpoints, the package takes forever to get where it needs to go.

• Heavy synchronous operations or unoptimized queries. JavaScript is single-threaded, meaning it handles tasks one by one. If the code blocks the event loop — say, with a slow database query — the whole server stops. As a result, one heavy operation delays every other incoming request.

• Improper use of async logic. Asynchronous programming involves using async/await and Promises. Developers might forget to “await” something or mismanage Promises, which causes subtle bugs and random slowdowns. Under higher loads, these issues can cascade into bigger problems.

• No caching or pagination in data-heavy routes. Imagine every time someone visits your blog, your backend has to go fetch all your blog posts from the database, even the old ones that haven’t changed in years. Without caching or pagination, your database becomes a huge bottleneck.

• Tightly coupled logic. When your business logic, database access, and request handling are all tangled together, it’s harder to scale or debug anything. This makes backend performance optimization tough and requires rewriting entire chunks of code.

What Do You Really Need from a Docker Developer?

So, how do you hire Express.js developers who won’t leave you with a laggy backend? Focus on devs who think about performance, structure, and scalability from the start. Here’s what separates them from the rest:

• Understands middleware flow and centralized error handling. Express.js relies heavily on middleware, and if a developer doesn’t understand how it flows, they’ll end up with spaghetti code and bugs that are impossible to trace. Look for someone who knows how to keep middleware clean and centralized.

• Implements caching and pagination in high-load routes. High-traffic endpoints shouldn’t hit the database in every single request. Skilled Express.js developers know when to add caching layers, like Redis or Memcached. They also know when to use pagination — retrieving data in smaller, manageable chunks — to reduce payloads.

• Uses async/await effectively and avoids blocking operations. A good Express.js dev understands async programming and knows how to write non-blocking code. They use async/await and Promises correctly, ensuring that heavy operations don’t block the main event loop.

• Reads logs and uses profiling tools to find performance issues. Performance problems rarely fix themselves. The right developer applies Express.js performance tips, reads server logs, and uses profiling tools like Node.js built-ins or third-party monitoring like Datadog or New Relic.

• Chooses database access methods based on performance needs. Object-relational mappers (ORMs) like Sequelize are great for speed of development — but not always for performance. Experienced devs know when to use an ORM, when to write raw queries, and how to structure data access for speed.

Interview Tips to Quickly Identify the Right Express.js Developers

Resumes and portfolios are good. But they don’t really show you how Express.js developers act when things get tough. Here are some practical ways to spot the right dev:

• Ask for examples of real-world performance issues they’ve solved.

• Give small tasks that test their architectural thinking.

• Check how they handle traffic spikes, timeouts, and API rate limiting.

• Prepare a tech task to see how they debug and optimize code.

Why Backend Performance Is a Long-Term Investment

It’s tempting to cut corners early on — launch fast, patch later. However, when it comes to a performant and scalable Express.js backend, that mindset can backfire.

You need Express.js developers not just to get work done today. Instead, you need them to build a system that won’t crash when your user base grows.

Here’s why backend performance is something you cannot treat as an afterthought:

• Poor backend performance leads to long-term scaling issues. A poorly structured backend might seem “good enough” at first. But it won’t stay that way. As your traffic grows, those small inefficiencies accumulate. And scaling such a fragile system means completely remaking big parts of it.

• Fixing it later is more expensive than building it right. Reworking backend logic, refactoring routes, optimizing queries — all of that takes time, money, and effort. It’s far cheaper to hire Express.js developers who build with performance in mind right away.

• Express.js apps are only fast when built well. This framework gives you speed — but only if your Express.js developer knows how to use it wisely. Without that knowledge, that “fast” framework can become slow and unstable.

Conclusion

When hiring Express.js developers, you need more than a basic tech skill assessment. Instead, focus on devs who build with backend performance and scalability in mind from the very beginning.

And if you’re after Express.js or Node.js developers for hire who get it right the first time, reach out to Integrio Systems. Having extensively worked on Node.js and Express.js projects, we’ll match you with developers who know how to keep your backend smooth, even under pressure.