ebd8573046
This is a small wrapper around fetchzip. It allows you to say:
src = fetchGitHub {
owner = "NixOS";
repo = "nix";
rev = "924e19341a5ee488634bc9ce1ea9758ac496afc3"; # or a tag
sha256 = "1ld1jc26wy0smkg63chvdzsppfw6zy1ykf3mmc50hkx397wcbl09";
};