AdonisJS vs Fastify
Which should you use? A side-by-side look at what each one does, who it suits, what it costs, how hard it is to set up, and where each falls short.
Open source · MIT
A TypeScript web framework for building web apps and API servers on Node.js.
Open source · MIT
A fast, low-overhead web framework for building servers and APIs with Node.js.
The short answer
Choose AdonisJS if you need…
- Developers who want a structured, batteries-included framework on Node.js
- TypeScript developers building full-stack web apps
- Teams building API servers or microservices who want an opinionated MVC layout
- Developers who want official packages that work together
Choose Fastify if you need…
- Node.js developers building JSON APIs or backend services
- Teams that care about request throughput and want a lightweight framework
- Projects that want schema-based validation of routes and responses
- Developers who want to organize code into reusable plugins
Side-by-side
| AdonisJS | Fastify | |
|---|---|---|
| Type | Library | Library |
| Price | Free and open source | Free and open source |
| Licence | MIT | MIT |
| GitHub stars | 19.2k | 37.3k |
| Setup difficulty | Intermediate | Beginner |
| How you get it | Install with a package manager | Install with a package manager |
| Main language | TypeScript | JavaScript |
| Last code update | 6 days ago | 4 days ago |
What each one is
AdonisJS
AdonisJS is a full-stack MVC web framework for Node.js, written in TypeScript. It provides a structured set of tools for building web applications and API servers, including testing support and an ecosystem of official packages. The README describes its focus as ergonomics and speed, with the aim of handling common web development chores so developers can work from a consistent API.
Fastify
Fastify is a framework for building web servers and APIs in Node.js. You define routes, such as a URL that returns data, and Fastify handles incoming requests with minimal extra work per request. It also offers a plugin system, input and output validation using JSON Schema, and built-in logging through Pino.
Best for
AdonisJS
- Developers who want a structured, batteries-included framework on Node.js
- TypeScript developers building full-stack web apps
- Teams building API servers or microservices who want an opinionated MVC layout
- Developers who want official packages that work together
Fastify
- Node.js developers building JSON APIs or backend services
- Teams that care about request throughput and want a lightweight framework
- Projects that want schema-based validation of routes and responses
- Developers who want to organize code into reusable plugins
Strengths
AdonisJS
- TypeScript-first design with a documented, consistent API
- Includes testing support and modern tooling out of the box
- Maintained by an active project with a large official package ecosystem (per the description)
Fastify
- The README reports high request throughput in a synthetic hello-world benchmark, with the caveat that real results depend on the application
- Supports JSON Schema validation and serialization for routes
- Includes a plugin architecture and hooks for extending behavior
Not ideal for
AdonisJS
- Beginners with no JavaScript or Node.js experience, since the framework assumes familiarity with TypeScript and MVC concepts
- People who prefer small, minimal libraries they assemble themselves, because AdonisJS brings a larger opinionated structure
Fastify
- Beginners who have not yet learned Node.js basics, since the framework assumes JavaScript familiarity
- Projects that need a non-Node.js language, because Fastify is for Node.js only
- Teams expecting a large built-in feature set; much functionality comes from plugins, per the docs
Trade-offs
AdonisJS
- The README is truncated and gives little detail on specific features, so the full scope is unclear from this source alone
- Being an opinionated MVC framework, it imposes a project structure that may not suit every team
Fastify
- Benchmark figures come from the maintainers' own synthetic test and may not match your workload
- The README's benchmark table lists an older Fastify version (4.0.0), so the numbers are not current
- Binding to 0.0.0.0 in containers requires care, since the README warns of security risks
Getting started
AdonisJS
Clone the repository
git clone https://github.com/adonisjs/coreFastify
Install Fastify in an existing project
npm i fastifyGenerate a new Fastify project
npm init fastifyFrequently asked questions
What is the difference between AdonisJS and Fastify?
AdonisJS: A TypeScript web framework for building web apps and API servers on Node.js. Fastify: A fast, low-overhead web framework for building servers and APIs with Node.js. AdonisJS suits developers who want a structured, batteries-included framework on node.js, while Fastify suits node.js developers building json apis or backend services.
Are AdonisJS and Fastify free?
AdonisJS: Free and open source. Fastify: Free and open source.
Which is easier to set up, AdonisJS or Fastify?
Fastify is easier to get started with (rated beginner); AdonisJS is rated intermediate and usually needs more setup.
Is AdonisJS or Fastify more popular?
Fastify has more GitHub stars (37.3k) than AdonisJS (19.2k). Popularity isn't the same as fit — check which one matches your use case above.
What are other alternatives to AdonisJS and Fastify?
Other options people compare them with include Express, Next.js, Vapor, Koa.
Keep comparing
Built from our catalogue entries for both products: open-source details come from each project's README (AI-assisted, refreshed weekly) and GitHub data; AI-tool details are editorial. Spotted something wrong? Let us know from either product's page.