[Nix-dev] github triggered builds

[Harmen]

Hi,

I'm trying to see how I can make my build processes easier with nix. So far
it's going pretty good and it's fun, although there was a lot of searching
online for scattered documents.

Want I want to do (as the first thing to change to nix in production) is to
port the building of some docker images I use for testing. The idea is to
have docker images build, tagged with their branch they come from, when someone
pushes something. The building and pushing an sich work. The .nix files live in
the repo, and with a `make docker` the image is build and uploaded. I'm very
happy to be able to build docker images without actually having to use docker
;)

So, what would be the recommended way to trigger the building process? I'm
currently using drone.io, but that works with containers. It works with nix,
when I give it the nixos/nix docker image, but building a node project takes
about 5 minutes, and drags in way too much from cache.nixos.org. I tried to
have it make a local nix binary-cache, but there are some problems there, but
drone also just doesn't fit the problem nicely.  Nix solves the problem of
versioning so much nicer than containers that I would prefer to use something
simpler. Hydra could work, but I'm a bit intimidated by that, and would like to
have something simpler for now.

The LT;DR: question: is there a simple nix based build system which can be
triggered via git{hub,lab} hooks?


Thanks!
Harmen
(If there is a better place to ask this, let me know)