anchor.diff:    # Contains the ruby version heuristics
     rubyVersion = import ./ruby-version.nix { inherit lib; };
   
  -  generic = { version, revision, sha256 }: let
  +  generic = { version, sha256 }: let
       ver = version;
       tag = ver.gitTag;
       atLeast30 = lib.versionAtLeast ver.majMin "3.0";
  
positive.code:           rm -rf $sourceRoot/{lib,test}/rubygems*
            cp -r ${rubygems}/lib/rubygems* $sourceRoot/lib
            cp -r ${rubygems}/test/rubygems $sourceRoot/test
          '' + opString buildFromGit ''
            cat <<EOF > $sourceRoot/revision.h
            #define RUBY_REVISION "${lib.substring 0 8 revision}"
            #define RUBY_FULL_REVISION "${revision}"
            EOF
          '';
  
          postPatch = ''
  
negative.code: in {
    ruby_2_7 = generic {
      version = rubyVersion "2" "7" "5" "";
      sha256 = "1wc1hwmz4m6iqlmqag8liyld917p6a8dvnhnpd1v8d8jl80bjm97";
    };
  
    ruby_3_0 = generic {
      version = rubyVersion "3" "0" "3" "";
      sha256 = "1b4j39zyyvdkf1ax2c6qfa40b4mxfkr87zghhw19fmnzn8f8d1im";
    };
  
    ruby_3_1 = generic {
      version = rubyVersion "3" "1" "1" "";
      sha256 = "sha256-/m5Hgt6XRDl43bqLpL440iKqJNw+PwKmqOdwHA7rYZ0=";
    };
  }
  