A few cleanups and renames. One feature remains...

pkgs/development/ruby-modules/bundler-app/default.nix

@@ -0,0 +1,47 @@
+{ lib, stdenv, callPackage, runCommand, ruby }@defs:
+
+# Use for simple installation of Ruby tools shipped in a Gem.
+# Start with a Gemfile that includes `gem <toolgem>`
+# > nix-shell -p bundler bundix
+# (shell)> bundle lock
+# (shell)> bundix
+# Then use rubyTool in the default.nix:
+
+# rubyTool { name = "gemifiedTool"; gemdir = ./.; exes = ["gemified-tool"]; }
+# The 'exes' parameter ensures that a copy of e.g. rake doesn't polute the system.
+{
+  name
+  # gemdir is the location of the Gemfile{,.lock} and gemset.nix; usually ./.
+, gemdir
+  # Exes is the list of executables provided by the gems in the Gemfile
+, exes ? []
+  # Scripts are ruby programs depend on gems in the Gemfile (e.g. scripts/rails)
+, scripts ? []
+, ruby ? defs.ruby
+, gemfile ? null
+, lockfile ? null
+, gemset ? null
+, preferLocalBuild ? false
+, allowSubstitutes ? false
+, meta ? {}
+, postBuild ? ""
+}@args:
+
+let
+  basicEnv = (callPackage ../bundled-common {}) args;
+
+  cmdArgs = removeAttrs args [ "name" "postBuild" ]
+  // { inherit preferLocalBuild allowSubstitutes; }; # pass the defaults
+in
+   runCommand name cmdArgs ''
+    mkdir -p $out/bin;
+      ${(lib.concatMapStrings (x: "ln -s '${basicEnv}/bin/${x}' $out/bin/${x};\n") exes)}
+      ${(lib.concatMapStrings (s: "makeWrapper $out/bin/$(basename ${s}) $srcdir/${s} " +
+              "--set BUNDLE_GEMFILE ${basicEnv.confFiles}/Gemfile "+
+              "--set BUNDLE_PATH ${basicEnv}/${ruby.gemPath} "+
+              "--set BUNDLE_FROZEN 1 "+
+              "--set GEM_HOME ${basicEnv}/${ruby.gemPath} "+
+              "--set GEM_PATH ${basicEnv}/${ruby.gemPath} "+
+              "--run \"cd $srcdir\";\n") scripts)}
+    ${postBuild}
+  ''