Are You Using NestJS?

Are you using NestJS? Then you should be. Read our latest guide to NestJS and what you need to know.

Matthew Foot

7 min read Reading Time

9 May 2022 Date Created

Are You Using NestJS?

While plenty of projects exist to boost productivity and efficiency for frontend Node.js developers, tools to help backend developers are sorely lacking.

Enter: NestJS, a fast and efficient framework designed to help both frontend and backend developers create testable, scalable, and maintainable applications for Node.js.

What Is NestJS?

If you’re familiar with Angular, React, or Vue, you’ll already be familiar with a lot of NestJS’ features. Think of it like Angular but mostly for backend developers.

Not familiar with Angular? Then you can think of NestJS as a simple, user-friendly framework for building Node.js server-side applications.

NestJS was originally conceived as a solution to the architecture problems found in other Node tools for creating monoliths and microservices. Built on HTTP frameworks like Express and Fastify, NestJS allows you to organise your code into clear components — making it entirely scalable, testable and loosely coupled. That means you can avoid the time-consuming refactoring that results from mistakes made when using the likes of Express or Koa alone.

The Key Components of NestJS

NestJS consists of three main components:

Controllers — Controllers are created using classes and decorators. They receive requests to your application and return responses to the client. Controllers can be configured to return standard or library-specific responses.
Providers — The term “providers” just refers to basic Nest classes, like services. These providers can be injected as a dependency and can be used with constructor-based or property-based injection.
Modules — Modules are NestJS’ key concept and they’re used to organise your app’s structure. Modules include providers and controllers, as well as imports and exports.

The Most Useful Features of NestJS

TypeScript — One key feature of NestJS is that it’s built with – and fully supports – TypeScript (though you can still code in pure JavaScript if you want to). TypeScript is popular for its developer experience and type safety; it ensures clean, bug-free, testable code that enhances efficiency. It also makes it easier to manage dependencies as they can be resolved by type.
Third-party module support — NestJS provides a level of abstraction from Express and Fastify while maintaining direct access to their APIs for the developer. That means you can use the framework with any of the third-party modules that are compatible with these frameworks (like GraphQL, TypeORM, Websockets, and more).
Pipes, Guards, and Interceptors — Like Angular, NestJS allows you to use interceptors, guards, and pipes to manipulate data before it’s saved to a database or returned to an application. This gives you an extra layer of control not present in other frameworks.
Native microservice support — NestJS was built with microservices in mind, so a great deal of the documentation is focused on specific techniques and recipes. The framework also allows your app components to run across microservices, HTTP platforms and WebSockets as it abstracts implementation details.

Possible Setbacks to NestJS

Sounds good so far, right? Well, there are some potential downsides to NestJS.

Over-abstraction of microservices — Some developers argue that NestJS’ built-in microservice abstraction is over-simplified, and won’t suit you if you need a granular level of control over modules.
Not for TypeScript critics — While NestJS can be used with JavaScript, it’s really designed to work with (and built on) TypeScript. If you’re not a fan, this might not be the framework for you.
Might not be suitable for complex API arguments — The custom decorators that come with NestJS aren’t well-suited to complex types. It may only suit you if you want to use simple API routes.
TypeORM can cause debugging issues — Some users have reported issues with debugging while using TypeORM (though switching to other ORM tools seems to resolve any problems).

The Big Advantages of NestJS

So we’ve seen some of the potential downsides, but what are the best things about NestJS?

Efficiency — From its use of TypeScript to its intuitive modular architecture, NextJS is designed to give you a fast and efficient development process.
Easy testing — NestJS’ organised architecture makes it incredibly easy to test your applications, eradicating the need for time-consuming refactoring.
Flexibility and compatibility — The framework is compatible with a huge range of third-party modules, and can be used to create monoliths, microservices, CLIs and many types of applications.
Growing community — Initially, NestJS was hampered slightly by poor documentation and support. But, as its user base grows, the framework enjoys an increasingly large community and support network.
Usability — Ultimately, one of NestJS’ greatest strengths is its ease of use. It provides an Angular-based framework that makes creating Node.js server-side applications easy. It also comes with a codebase and documentation that are both open source and regularly maintained.

The Nest Big Thing?

NestJS currently has over 46k stars on GitHub and is one of the quickest-growing Node.js frameworks of the last few years. Though not without its detractors, the framework provides a fast, efficient and easy way to create flexible, scalable and testable Node.js applications.

Whether you’re looking for a backend development tool to mimic Angular – or you just want an accessible and abstracted version of ExpressJS or Fastify – this is the framework to learn.