The software driving the GAVO data center is available under the GPL. There are some libraries and user tools that came into being in the close vicinity of the data center. All that can be downloaded here.
If you are interested in using this software, it is recommended to run a Debian-derived operating system and install the software through apt. See our page on the GAVO APT repository. However, with a bit of manual effort, you can get it to work on other machines, too.
Software packages distributed by the GAVO data center include:
There is work-in-progress documentation on DaCHS and the component libraries. In particular, you may want to skim over the tutorial to get an idea what you can do with DaCHS.
For Debian squeeze, we recommend the installation of our updated nevow module. If you don't you will see some depreciation warnings (that have nothing to do with DaCHS and are harmless; but they're ugly anyway).