nix: a shell.nix for running go test
Created by: keegancsmith
This is a first step towards support nix in our development environment. It only covers go test and yarn. I am still a nix noob as well, so could be much better.
Different to our usual environment is that it runs postgres under ~/.sourcegraph with a unix socket. No need to manage service. Must remember to run pg_ctl shutdown if you want to stop.