example.nix

   1 { pkgs ? import <nixpkgs> {} }: with pkgs;
   2
   3 let clever-tools = fetchFromGitHub {
   4                      owner  = "fretlink";
   5                      repo   = "clever-tools-nix";
   6                      rev    = "DESIRED_REVISION_HASH";
   7                      sha256 = "CONTENT_HASH";
   8                    };
   9 in (import clever-tools {}).latest # select appropriate version