Fastify v3 released

2 min readJul 7, 2020
Courtesy of Arnaud Gillard

We are thrilled to announce the final release of the third major version of Fastify! In April this year, we published the first Fastify v3 Release Candidate Since then we have been focusing our efforts on porting all modules maintained in the Fastify GitHub organization to Fastify v3. We would like to thank our amazing community for all of the work they put in to making this a reality.

This new version of Fastify includes some changes that will allow you to have an even better experience with Fastify, starting from the brand new type definitions, the new full support of Express middleware, and the refactored request validation.

Full release notes can be found here, with a handy guide to help you migrate from v2.

The most noticeable breaking changes are:

Fastify v3 can now be installed with npm install fastify.

Please let us know about any compatibility and upgrade issues at fastify/help!

Updated benchmarks


  • More than 2300 commits
  • More than 130 releases,
  • More than 1000 forks
  • Used in production by more than 20 companies
  • More than 540k downloads per month
  • 136 officially recognized plugins.

This wouldn’t have been possible without the help of our fantastic team, which we would like to thank for all their hard work:

allevo, cemremengu, davidmarkclements, delvedor, eomm, Ethan-Arrowood, jsumners, mcollina, SerayaEryn, and starptech.

We also want to thank our amazing contributors, for all the bug reports, pull requests, and faith in the Fastify vision!

Fastify v2 will reach End of Life in early January 2021, but until then we will continue to maintain this version with security patches and critical fixes.

Fastify v3 is covered by our LTS support cycle. This means at least six months of active support is provided by our core team, plus an additional six months of security fixes after LTS goes into maintenance, which will occur upon the release of Fastify v4.

Happy coding!

The Fastify Team