This repository aims to install/build hieracles 0.4.2 with pre-generated
gemset.nix and Gemfile.lock files.
$ nix-build
$ ./result/bin/hieracles -v
0.4.2
$ nix-env -f default.nix -i hieracles
$ hieracles -v
0.4.2
$ nix-shell
$ hieracles -v
0.4.2