Hydra

Hydra build farm

About

Hydra is a Nix-based continuous build system. It continuously checks out sources of software projects from version management systems to build, test and release them. The build tasks are described using Nix expressions. This allows a Hydra build task to specify all the dependencies needed to build or test a project. It supports a number of operating systems, such as various Linux flavours, Mac OS X, and Windows.

At Delft University of Technology we run a Hydra-based build farm to build and test the NixOS Linux distribution, the Nix Packages collection, the Stratego/XT program transformation system, and various other open source projects. If you want to use our build farm for your open source project, please let us know.

Documentation

There is a draft paper about Hydra. There are also some (incomplete and somewhat outdated) instructions available on how to set up your own Hydra server.

Feedback

If you would like to give some feedback, or report some bugs, please visit,