The Vala compiler also supports a language called Genie, which is very similar to Python but compiles down to C in the same way that Vala does. Genie files can be mixed with Vala files on the command line.
https://wiki.gnome.org/Projects/GenieAutomake does not currently support files with the extension .gs - this is easily confirmed by adding one to the _SOURCE primary for a Vala project.
This patch adds support for Genie files. The patch includes modifications to the existing Vala tests to ensure that it functions correctly. The patch does not appear to affect any other modules when the entire test suite is run.
vala-genie-support.patch