Glossary · Web & App Development
Express
Overview
What Express is
Express, often called Express.js, is a minimal and unopinionated web framework for Node.js. It handles the essentials of a web server—routing requests to the right code and passing them through a chain of middleware functions that can read, modify, or respond to each request. It adds little on top of Node itself, leaving architecture decisions to the developer.
Why Express matters
Express has been the de facto standard for Node.js backends for over a decade, with a huge ecosystem of compatible middleware for authentication, logging, security, and more. Many higher-level frameworks, including NestJS, run on top of it. Its simplicity is the point: it is fast to learn and flexible enough for anything from a small API to a large service.
How an agency uses Express
For backend development and app backend and API development, Express is a dependable choice for REST APIs, webhooks, and lightweight services where a heavier framework would be overkill. Its flexibility does require discipline on larger projects, so an experienced in-house team sets conventions up front, or reaches for a structured framework like NestJS when a codebase is expected to grow.
Where we use it
Related Zen in Tech services
How our team puts Express to work in real projects.
FAQ
Express — common questions
Is Express still relevant?
Yes. Express remains the most widely used Node.js web framework, and Express 5 was released to modernize it. Its enormous ecosystem and simplicity keep it a common foundation for APIs and for other frameworks built on top of it.
Express vs NestJS — which should I use?
Use Express for small, straightforward services where you want full control and minimal overhead. Use NestJS—which itself runs on Express—when you need built-in structure, dependency injection, and consistency across a larger team or codebase.
Is Express good for large applications?
It can be, but Express provides no built-in structure, so large teams must impose their own conventions to avoid inconsistency. For big, long-lived projects, many teams choose a more opinionated framework built on Express, such as NestJS.
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