It does not compile.
I "patched" app.vala, so it does compile. But i didn't knew what I was doing. The result then compiles, but does not work. Segfault with 0.14 and no function with 0.16.
I don't know how attach a patch, so here it is:
Work with new parameters for Socket#receive. Fixes #1
Thanks for the heads up. Fixed by 8227a33 (at least for me on 0.14.2). Let me know if there are any problems.
I would strongly recommend using another framework, (Valum maybe). Valatra was done just as a small project to learn Vala, and hasn't been looked at since the summer.