<h3>1.2. About Us</h3>
Hydra is the successor of the Nix Buildfarm, which was developed in
tandem with the Nix software deployment system. Nix was originally
developed at the Department of Information and Computing Sciences,
Utrecht University by the TraCE project (2003-2008). The project was
funded by the Software Engineering Research Program Jacquard to
improve the support for variability in software systems.  Funding for
the development of Nix and Hydra is now provided by the NIRICT LaQuSo
Build Farm project.
<h3>1.3. About this Manual</h3>
This manual tells you how to install the Hydra buildfarm software on
your own server and how to operate that server using its web
interface.

<h3>1.2. Hydra at nixos.org</h3>

<h3>1.4. License</h3>
Hydra is free software; you can redistribute it and/or modify it under
the terms of the GNU Lesser General Public License as published by the
Free Software Foundation; either version 2.1 of the License, or (at
your option) any later version. Hydra is distributed in the hope that
it will be useful, but WITHOUT ANY WARRANTY; without even the implied
warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See
the GNU Lesser General Public License for more details.
<h3>1.5. Hydra at nixos.org</h3>

<h3>1.3. Hydra on your own buildfarm</h3>

<h3>1.6. Hydra on your own buildfarm</h3>

We assume that you have 

To run Hydra you need a Linux server with at least a considerable
amount of diskspace to store builds. A multi-core machine is not a
waste since Hydra can schedule multiple simultaneous build jobs.

To run Hydra you need a Linux server.  For small projects, Hydra can
be run on any reasonably modern machine. For individual projects you
can even run Hydra on a laptop. However, the charm of a buildfarm
server is usually that it operates without disturbing the developer's
working environment and can serve releases over the internet. In
conjunction you should typically have your source code administered in
a version management system, such as subversion. Therefore, you will
probably want to install a server that is connected to the
internet. To scale up to large and/or many projects, you will need at
least a considerable amount of diskspace to store builds. Since Hydra
can schedule multiple simultaneous build jobs, it can be useful to
have a multi-core machine, and/or attach multiple build machines in a
network to the central Hydra server.

A project definition consists of some general information 

A project definition consists of some general information and a set of
jobsets. We start with the general information.