about summary refs log tree commit diff
path: root/nixpkgs/pkgs/development/ruby-modules
diff options
context:
space:
mode:
Diffstat (limited to 'nixpkgs/pkgs/development/ruby-modules')
-rw-r--r--nixpkgs/pkgs/development/ruby-modules/bundix/default.nix44
-rw-r--r--nixpkgs/pkgs/development/ruby-modules/bundled-common/default.nix158
-rw-r--r--nixpkgs/pkgs/development/ruby-modules/bundled-common/functions.nix93
-rw-r--r--nixpkgs/pkgs/development/ruby-modules/bundled-common/gen-bin-stubs.rb48
-rw-r--r--nixpkgs/pkgs/development/ruby-modules/bundled-common/test.nix50
-rw-r--r--nixpkgs/pkgs/development/ruby-modules/bundler-app/default.nix63
-rw-r--r--nixpkgs/pkgs/development/ruby-modules/bundler-env/default.nix59
-rw-r--r--nixpkgs/pkgs/development/ruby-modules/bundler-env/test.nix33
-rw-r--r--nixpkgs/pkgs/development/ruby-modules/bundler-env/test/Gemfile0
-rw-r--r--nixpkgs/pkgs/development/ruby-modules/bundler-env/test/Gemfile.lock0
-rw-r--r--nixpkgs/pkgs/development/ruby-modules/bundler-env/test/gemset.nix10
-rw-r--r--nixpkgs/pkgs/development/ruby-modules/bundler/default.nix14
-rw-r--r--nixpkgs/pkgs/development/ruby-modules/gem-config/default.nix438
-rw-r--r--nixpkgs/pkgs/development/ruby-modules/gem-config/mkrf_conf_xapian.rb14
-rw-r--r--nixpkgs/pkgs/development/ruby-modules/gem-config/xapian-Rakefile38
-rw-r--r--nixpkgs/pkgs/development/ruby-modules/gem/default.nix228
-rw-r--r--nixpkgs/pkgs/development/ruby-modules/gem/gem-post-build.rb81
-rw-r--r--nixpkgs/pkgs/development/ruby-modules/gem/nix-bundle-install.rb182
-rwxr-xr-xnixpkgs/pkgs/development/ruby-modules/runtests.sh6
-rw-r--r--nixpkgs/pkgs/development/ruby-modules/solargraph/Gemfile3
-rw-r--r--nixpkgs/pkgs/development/ruby-modules/solargraph/Gemfile.lock50
-rw-r--r--nixpkgs/pkgs/development/ruby-modules/solargraph/default.nix15
-rw-r--r--nixpkgs/pkgs/development/ruby-modules/solargraph/gemset.nix159
-rw-r--r--nixpkgs/pkgs/development/ruby-modules/testing/assertions.nix28
-rw-r--r--nixpkgs/pkgs/development/ruby-modules/testing/driver.nix20
-rw-r--r--nixpkgs/pkgs/development/ruby-modules/testing/stubs.nix30
-rw-r--r--nixpkgs/pkgs/development/ruby-modules/testing/tap-support.nix21
-rw-r--r--nixpkgs/pkgs/development/ruby-modules/testing/testing.nix62
28 files changed, 1947 insertions, 0 deletions
diff --git a/nixpkgs/pkgs/development/ruby-modules/bundix/default.nix b/nixpkgs/pkgs/development/ruby-modules/bundix/default.nix
new file mode 100644
index 000000000000..92f14114cf10
--- /dev/null
+++ b/nixpkgs/pkgs/development/ruby-modules/bundix/default.nix
@@ -0,0 +1,44 @@
+{ buildRubyGem, fetchFromGitHub, makeWrapper, lib, bundler, nix,
+  nix-prefetch-git }:
+
+buildRubyGem rec {
+  inherit (bundler) ruby;
+
+  name = "${gemName}-${version}";
+  gemName = "bundix";
+  version = "2.4.1";
+
+  src = fetchFromGitHub {
+    owner = "manveru";
+    repo = "bundix";
+    rev = version;
+    sha256 = "175qmv7dj7v50v71b78dzn5pb4a35ml6p15asks9q1rrlkz0n4gn";
+  };
+
+  buildInputs = [ ruby bundler ];
+  nativeBuildInputs = [ makeWrapper ];
+
+  preFixup = ''
+    wrapProgram $out/bin/bundix \
+                --prefix PATH : "${nix.out}/bin" \
+                --prefix PATH : "${nix-prefetch-git.out}/bin" \
+                --prefix PATH : "${bundler.out}/bin" \
+                --set GEM_HOME "${bundler}/${bundler.ruby.gemPath}" \
+                --set GEM_PATH "${bundler}/${bundler.ruby.gemPath}"
+  '';
+
+  meta = {
+    inherit version;
+    description = "Creates Nix packages from Gemfiles";
+    longDescription = ''
+      This is a tool that converts Gemfile.lock files to nix expressions.
+
+      The output is then usable by the bundlerEnv derivation to list all the
+      dependencies of a ruby package.
+    '';
+    homepage = https://github.com/manveru/bundix;
+    license = "MIT";
+    maintainers = with lib.maintainers; [ manveru qyliss zimbatm ];
+    platforms = lib.platforms.all;
+  };
+}
diff --git a/nixpkgs/pkgs/development/ruby-modules/bundled-common/default.nix b/nixpkgs/pkgs/development/ruby-modules/bundled-common/default.nix
new file mode 100644
index 000000000000..c31dfb63b3cd
--- /dev/null
+++ b/nixpkgs/pkgs/development/ruby-modules/bundled-common/default.nix
@@ -0,0 +1,158 @@
+{ stdenv, runCommand, ruby, lib
+, defaultGemConfig, buildRubyGem, buildEnv
+, makeWrapper
+, bundler
+}@defs:
+
+{
+  name ? null
+, pname ? null
+, mainGemName ? null
+, gemdir ? null
+, gemfile ? null
+, lockfile ? null
+, gemset ? null
+, ruby ? defs.ruby
+, gemConfig ? defaultGemConfig
+, postBuild ? null
+, document ? []
+, meta ? {}
+, groups ? null
+, ignoreCollisions ? false
+, buildInputs ? []
+, ...
+}@args:
+
+assert name == null -> pname != null;
+
+with  import ./functions.nix { inherit lib gemConfig; };
+
+let
+  gemFiles = bundlerFiles args;
+
+  importedGemset = if builtins.typeOf gemFiles.gemset != "set"
+    then import gemFiles.gemset
+    else gemFiles.gemset;
+
+  filteredGemset = filterGemset { inherit ruby groups; } importedGemset;
+
+  configuredGemset = lib.flip lib.mapAttrs filteredGemset (name: attrs:
+    applyGemConfigs (attrs // { inherit ruby; gemName = name; })
+  );
+
+  hasBundler = builtins.hasAttr "bundler" filteredGemset;
+
+  bundler =
+    if hasBundler then gems.bundler
+    else defs.bundler.override (attrs: { inherit ruby; });
+
+  gems = lib.flip lib.mapAttrs configuredGemset (name: attrs: buildGem name attrs);
+
+  name' = if name != null then
+    name
+  else
+    let
+      gem = gems."${pname}";
+      version = gem.version;
+    in
+      "${pname}-${version}";
+
+  pname' = if pname != null then
+    pname
+  else
+    name;
+
+  copyIfBundledByPath = { bundledByPath ? false, ...}:
+  (if bundledByPath then
+      assert gemFiles.gemdir != null; "cp -a ${gemFiles.gemdir}/* $out/" #*/
+    else ""
+  );
+
+  maybeCopyAll = pkgname: if pkgname == null then "" else
+  let
+    mainGem = gems."${pkgname}" or (throw "bundlerEnv: gem ${pkgname} not found");
+  in
+    copyIfBundledByPath mainGem;
+
+  # We have to normalize the Gemfile.lock, otherwise bundler tries to be
+  # helpful by doing so at run time, causing executables to immediately bail
+  # out. Yes, I'm serious.
+  confFiles = runCommand "gemfile-and-lockfile" {} ''
+    mkdir -p $out
+    ${maybeCopyAll mainGemName}
+    cp ${gemFiles.gemfile} $out/Gemfile || ls -l $out/Gemfile
+    cp ${gemFiles.lockfile} $out/Gemfile.lock || ls -l $out/Gemfile.lock
+  '';
+
+  buildGem = name: attrs: (
+    let
+      gemAttrs = composeGemAttrs ruby gems name attrs;
+    in
+    if gemAttrs.type == "path" then
+      pathDerivation (gemAttrs.source // gemAttrs)
+    else
+      buildRubyGem gemAttrs
+  );
+
+  envPaths = lib.attrValues gems ++ lib.optional (!hasBundler) bundler;
+
+  basicEnv = buildEnv {
+    inherit buildInputs ignoreCollisions;
+
+    name = name';
+
+    paths = envPaths;
+    pathsToLink = [ "/lib" ];
+
+    postBuild = genStubsScript (defs // args // {
+      inherit confFiles bundler groups;
+      binPaths = envPaths;
+    }) + lib.optionalString (postBuild != null) postBuild;
+
+    meta = { platforms = ruby.meta.platforms; } // meta;
+
+    passthru = rec {
+      inherit ruby bundler gems confFiles envPaths;
+
+      wrappedRuby = stdenv.mkDerivation {
+        name = "wrapped-ruby-${pname'}";
+        nativeBuildInputs = [ makeWrapper ];
+        buildCommand = ''
+          mkdir -p $out/bin
+          for i in ${ruby}/bin/*; do
+            makeWrapper "$i" $out/bin/$(basename "$i") \
+              --set BUNDLE_GEMFILE ${confFiles}/Gemfile \
+              --set BUNDLE_PATH ${basicEnv}/${ruby.gemPath} \
+              --set BUNDLE_FROZEN 1 \
+              --set GEM_HOME ${basicEnv}/${ruby.gemPath} \
+              --set GEM_PATH ${basicEnv}/${ruby.gemPath}
+          done
+        '';
+      };
+
+      env = let
+        irbrc = builtins.toFile "irbrc" ''
+          if !(ENV["OLD_IRBRC"].nil? || ENV["OLD_IRBRC"].empty?)
+            require ENV["OLD_IRBRC"]
+          end
+          require 'rubygems'
+          require 'bundler/setup'
+        '';
+        in stdenv.mkDerivation {
+          name = "${pname'}-interactive-environment";
+          nativeBuildInputs = [ wrappedRuby basicEnv ];
+          shellHook = ''
+            export OLD_IRBRC=$IRBRC
+            export IRBRC=${irbrc}
+          '';
+          buildCommand = ''
+            echo >&2 ""
+            echo >&2 "*** Ruby 'env' attributes are intended for interactive nix-shell sessions, not for building! ***"
+            echo >&2 ""
+            exit 1
+          '';
+        };
+    };
+  };
+in
+  basicEnv
diff --git a/nixpkgs/pkgs/development/ruby-modules/bundled-common/functions.nix b/nixpkgs/pkgs/development/ruby-modules/bundled-common/functions.nix
new file mode 100644
index 000000000000..6324f27e9faf
--- /dev/null
+++ b/nixpkgs/pkgs/development/ruby-modules/bundled-common/functions.nix
@@ -0,0 +1,93 @@
+{ lib, gemConfig, ... }:
+
+let
+  inherit (lib) attrValues concatMap converge filterAttrs getAttrs
+                intersectLists;
+
+in rec {
+  bundlerFiles = {
+    gemfile ? null
+  , lockfile ? null
+  , gemset ? null
+  , gemdir ? null
+  , ...
+  }: {
+    inherit gemdir;
+
+    gemfile =
+    if gemfile == null then assert gemdir != null; gemdir + "/Gemfile"
+    else gemfile;
+
+    lockfile =
+    if lockfile == null then assert gemdir != null; gemdir + "/Gemfile.lock"
+    else lockfile;
+
+    gemset =
+    if gemset == null then assert gemdir != null; gemdir + "/gemset.nix"
+    else gemset;
+  };
+
+  filterGemset = { ruby, groups, ... }: gemset:
+    let
+      platformGems = filterAttrs (_: platformMatches ruby) gemset;
+      directlyMatchingGems = filterAttrs (_: groupMatches groups) platformGems;
+
+      expandDependencies = gems:
+        let
+          depNames = concatMap (gem: gem.dependencies or []) (attrValues gems);
+          deps = getAttrs depNames platformGems;
+        in
+          gems // deps;
+    in
+      converge expandDependencies directlyMatchingGems;
+
+  platformMatches = {rubyEngine, version, ...}: attrs: (
+  !(attrs ? "platforms") ||
+  builtins.length attrs.platforms == 0 ||
+    builtins.any (platform:
+      platform.engine == rubyEngine &&
+        (!(platform ? "version") || platform.version == version.majMin)
+    ) attrs.platforms
+  );
+
+  groupMatches = groups: attrs:
+    groups == null || !(attrs ? "groups") ||
+      (intersectLists (groups ++ [ "default" ]) attrs.groups) != [];
+
+  applyGemConfigs = attrs:
+    (if gemConfig ? "${attrs.gemName}"
+    then attrs // gemConfig."${attrs.gemName}" attrs
+    else attrs);
+
+  genStubsScript = { lib, ruby, confFiles, bundler, groups, binPaths, ... }: ''
+      ${ruby}/bin/ruby ${./gen-bin-stubs.rb} \
+        "${ruby}/bin/ruby" \
+        "${confFiles}/Gemfile" \
+        "$out/${ruby.gemPath}" \
+        "${bundler}/${ruby.gemPath}" \
+        ${lib.escapeShellArg binPaths} \
+        ${lib.escapeShellArg groups}
+    '';
+
+  pathDerivation = { gemName, version, path, ...  }:
+    let
+      res = {
+          type = "derivation";
+          bundledByPath = true;
+          name = gemName;
+          version = version;
+          outPath = path;
+          outputs = [ "out" ];
+          out = res;
+          outputName = "out";
+        };
+    in res;
+
+  composeGemAttrs = ruby: gems: name: attrs: ((removeAttrs attrs ["platforms"]) // {
+    inherit ruby;
+    inherit (attrs.source) type;
+    source = removeAttrs attrs.source ["type"];
+    gemName = name;
+    gemPath = map (gemName: gems."${gemName}") (attrs.dependencies or []);
+  });
+}
diff --git a/nixpkgs/pkgs/development/ruby-modules/bundled-common/gen-bin-stubs.rb b/nixpkgs/pkgs/development/ruby-modules/bundled-common/gen-bin-stubs.rb
new file mode 100644
index 000000000000..fe8c43f55ed1
--- /dev/null
+++ b/nixpkgs/pkgs/development/ruby-modules/bundled-common/gen-bin-stubs.rb
@@ -0,0 +1,48 @@
+require 'rbconfig'
+require 'rubygems'
+require 'rubygems/specification'
+require 'fileutils'
+
+# args/settings
+out = ENV["out"]
+ruby = ARGV[0]
+gemfile = ARGV[1]
+bundle_path = ARGV[2]
+bundler_gem_path = ARGV[3]
+paths = ARGV[4].split
+groups = ARGV[5].split
+
+# generate binstubs
+FileUtils.mkdir_p("#{out}/bin")
+paths.each do |path|
+  next unless File.directory?("#{path}/nix-support/gem-meta")
+
+  name = File.read("#{path}/nix-support/gem-meta/name")
+  executables = File.read("#{path}/nix-support/gem-meta/executables")
+    .force_encoding('UTF-8').split
+  executables.each do |exe|
+    File.open("#{out}/bin/#{exe}", "w") do |f|
+      f.write(<<-EOF)
+#!#{ruby}
+#
+# This file was generated by Nix.
+#
+# The application '#{exe}' is installed as part of a gem, and
+# this file is here to facilitate running it.
+#
+
+ENV["BUNDLE_GEMFILE"] = #{gemfile.dump}
+ENV["BUNDLE_PATH"] = #{bundle_path.dump}
+ENV['BUNDLE_FROZEN'] = '1'
+
+Gem.use_paths(#{bundler_gem_path.dump}, ENV["GEM_PATH"])
+
+require 'bundler'
+Bundler.setup(#{groups.map(&:dump).join(', ')})
+
+load Gem.bin_path(#{name.dump}, #{exe.dump})
+EOF
+      FileUtils.chmod("+x", "#{out}/bin/#{exe}")
+    end
+  end
+end
diff --git a/nixpkgs/pkgs/development/ruby-modules/bundled-common/test.nix b/nixpkgs/pkgs/development/ruby-modules/bundled-common/test.nix
new file mode 100644
index 000000000000..7c5932c4e761
--- /dev/null
+++ b/nixpkgs/pkgs/development/ruby-modules/bundled-common/test.nix
@@ -0,0 +1,50 @@
+{ stdenv, writeText, lib, ruby, defaultGemConfig, callPackage, test, stubs, should }:
+let
+  testConfigs = {
+    inherit lib;
+    gemConfig =  defaultGemConfig;
+  };
+  functions = (import ./functions.nix testConfigs);
+in
+  builtins.concatLists [
+    ( test.run "All set, no gemdir" (functions.bundlerFiles {
+      gemfile  = test/Gemfile;
+      lockfile = test/Gemfile.lock;
+      gemset   = test/gemset.nix;
+    }) {
+      gemfile  = should.equal test/Gemfile;
+      lockfile = should.equal test/Gemfile.lock;
+      gemset   = should.equal test/gemset.nix;
+    })
+
+    ( test.run "Just gemdir" (functions.bundlerFiles {
+      gemdir = test/.;
+    }) {
+      gemfile  = should.equal test/Gemfile;
+      lockfile = should.equal test/Gemfile.lock;
+      gemset   = should.equal test/gemset.nix;
+    })
+
+    ( test.run "Gemset and dir" (functions.bundlerFiles {
+      gemdir = test/.;
+      gemset = test/extraGemset.nix;
+    }) {
+      gemfile  = should.equal test/Gemfile;
+      lockfile = should.equal test/Gemfile.lock;
+      gemset   = should.equal test/extraGemset.nix;
+    })
+
+    ( test.run "Filter empty gemset" {} (set: functions.filterGemset {inherit ruby; groups = ["default"]; } set == {}))
+    ( let gemSet = { test = { groups = ["x" "y"]; }; };
+      in
+      test.run "Filter matches a group" gemSet (set: functions.filterGemset {inherit ruby; groups = ["y" "z"];} set == gemSet))
+    ( let gemSet = { test = { platforms = []; }; };
+      in
+      test.run "Filter matches empty platforms list" gemSet (set: functions.filterGemset {inherit ruby; groups = [];} set == gemSet))
+    ( let gemSet = { test = { platforms = [{engine = ruby.rubyEngine; version = ruby.version.majMin;}]; }; };
+      in
+      test.run "Filter matches on platform" gemSet (set: functions.filterGemset {inherit ruby; groups = [];} set == gemSet))
+    ( let gemSet = { test = { groups = ["x" "y"]; }; };
+      in
+      test.run "Filter excludes based on groups" gemSet (set: functions.filterGemset {inherit ruby; groups = ["a" "b"];} set == {}))
+  ]
diff --git a/nixpkgs/pkgs/development/ruby-modules/bundler-app/default.nix b/nixpkgs/pkgs/development/ruby-modules/bundler-app/default.nix
new file mode 100644
index 000000000000..d0ad56538b94
--- /dev/null
+++ b/nixpkgs/pkgs/development/ruby-modules/bundler-app/default.nix
@@ -0,0 +1,63 @@
+{ lib, stdenv, callPackage, runCommand, makeWrapper, 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 { pname = "gemifiedTool"; gemdir = ./.; exes = ["gemified-tool"]; }
+# The 'exes' parameter ensures that a copy of e.g. rake doesn't polute the system.
+{
+  # use the name of the name in question; its version will be picked up from the gemset
+  pname
+  # 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
+, installManpages ? true
+, meta ? {}
+, buildInputs ? []
+, postBuild ? ""
+, gemConfig ? null
+, passthru ? {}
+}@args:
+
+let
+  basicEnv = (callPackage ../bundled-common {}) args;
+
+  cmdArgs = removeAttrs args [ "pname" "postBuild" "gemConfig" ] // {
+    inherit preferLocalBuild allowSubstitutes; # pass the defaults
+
+    buildInputs = buildInputs ++ lib.optional (scripts != []) makeWrapper;
+  };
+in
+  runCommand basicEnv.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)}
+
+    ${lib.optionalString installManpages ''
+    for section in {1..9}; do
+      mandir="$out/share/man/man$section"
+      find -L ${basicEnv}/${ruby.gemPath}/gems/${basicEnv.name} \( -wholename "*/man/*.$section" -o -wholename "*/man/man$section/*.$section" \) -print -execdir mkdir -p $mandir \; -execdir cp '{}' $mandir \;
+    done
+    ''}
+
+    ${postBuild}
+  ''
diff --git a/nixpkgs/pkgs/development/ruby-modules/bundler-env/default.nix b/nixpkgs/pkgs/development/ruby-modules/bundler-env/default.nix
new file mode 100644
index 000000000000..5d1489ba2005
--- /dev/null
+++ b/nixpkgs/pkgs/development/ruby-modules/bundler-env/default.nix
@@ -0,0 +1,59 @@
+{ ruby, lib, callPackage, defaultGemConfig, buildEnv, bundler }@defs:
+
+{ name ? null
+, pname ? null
+, gemdir ? null
+, gemfile ? null
+, lockfile ? null
+, gemset ? null
+, groups ? ["default"]
+, ruby ? defs.ruby
+, gemConfig ? defaultGemConfig
+, postBuild ? null
+, document ? []
+, meta ? {}
+, ignoreCollisions ? false
+, ...
+}@args:
+
+let
+  inherit (import ../bundled-common/functions.nix {inherit lib ruby gemConfig groups; }) genStubsScript;
+
+  basicEnv = (callPackage ../bundled-common {}) (args // { inherit pname name; mainGemName = pname; });
+
+  inherit (basicEnv) envPaths;
+  # Idea here is a mkDerivation that gen-bin-stubs new stubs "as specified" -
+  # either specific executables or the bin/ for certain gem(s), but
+  # incorporates the basicEnv as a requirement so that its $out is in our path.
+
+  # When stubbing the bins for a gem, we should use the gem expression
+  # directly, which means that basicEnv should somehow make it available.
+
+  # Different use cases should use different variations on this file, rather
+  # than the expression trying to deduce a use case.
+
+  # The basicEnv should be put into passthru so that e.g. nix-shell can use it.
+in
+  if pname == null then
+    basicEnv // { inherit name basicEnv; }
+  else
+    (buildEnv {
+      inherit ignoreCollisions;
+
+      name = basicEnv.name;
+
+      paths = envPaths;
+      pathsToLink = [ "/lib" ];
+
+      postBuild = genStubsScript {
+        inherit lib ruby bundler groups;
+        confFiles = basicEnv.confFiles;
+        binPaths = [ basicEnv.gems."${pname}" ];
+      } + lib.optionalString (postBuild != null) postBuild;
+
+      meta = { platforms = ruby.meta.platforms; } // meta;
+      passthru = basicEnv.passthru // {
+        inherit basicEnv;
+        inherit (basicEnv) env;
+      };
+    })
diff --git a/nixpkgs/pkgs/development/ruby-modules/bundler-env/test.nix b/nixpkgs/pkgs/development/ruby-modules/bundler-env/test.nix
new file mode 100644
index 000000000000..e42f1bf25711
--- /dev/null
+++ b/nixpkgs/pkgs/development/ruby-modules/bundler-env/test.nix
@@ -0,0 +1,33 @@
+{ stdenv, writeText, lib, ruby, defaultGemConfig, callPackage, test, stubs, should}:
+let
+  bundlerEnv = callPackage ./default.nix stubs // {
+    basicEnv = callPackage ../bundled-common stubs;
+  };
+
+  justName = bundlerEnv {
+    name = "test-0.1.2";
+    gemset = ./test/gemset.nix;
+  };
+
+  pnamed = bundlerEnv {
+    pname = "test";
+    gemdir = ./test;
+    gemset = ./test/gemset.nix;
+    gemfile = ./test/Gemfile;
+    lockfile = ./test/Gemfile.lock;
+  };
+in
+  builtins.concatLists [
+    (test.run "bundlerEnv { name }" justName {
+      name = should.equal "test-0.1.2";
+    })
+    (test.run "bundlerEnv { pname }" pnamed
+    [
+      (should.haveKeys [ "name" "env" "postBuild" ])
+      {
+        name = should.equal "test-0.1.2";
+        env = should.beASet;
+        postBuild = should.havePrefix "/nix/store";
+      }
+    ])
+  ]
diff --git a/nixpkgs/pkgs/development/ruby-modules/bundler-env/test/Gemfile b/nixpkgs/pkgs/development/ruby-modules/bundler-env/test/Gemfile
new file mode 100644
index 000000000000..e69de29bb2d1
--- /dev/null
+++ b/nixpkgs/pkgs/development/ruby-modules/bundler-env/test/Gemfile
diff --git a/nixpkgs/pkgs/development/ruby-modules/bundler-env/test/Gemfile.lock b/nixpkgs/pkgs/development/ruby-modules/bundler-env/test/Gemfile.lock
new file mode 100644
index 000000000000..e69de29bb2d1
--- /dev/null
+++ b/nixpkgs/pkgs/development/ruby-modules/bundler-env/test/Gemfile.lock
diff --git a/nixpkgs/pkgs/development/ruby-modules/bundler-env/test/gemset.nix b/nixpkgs/pkgs/development/ruby-modules/bundler-env/test/gemset.nix
new file mode 100644
index 000000000000..53f15f96bc6d
--- /dev/null
+++ b/nixpkgs/pkgs/development/ruby-modules/bundler-env/test/gemset.nix
@@ -0,0 +1,10 @@
+{
+  test = {
+    source = {
+      remotes = ["https://rubygems.org"];
+      sha256 = "1j5r0anj8m4qlf2psnldip4b8ha2bsscv11lpdgnfh4nnchzjnxw";
+      type = "gem";
+    };
+    version = "0.1.2";
+  };
+}
diff --git a/nixpkgs/pkgs/development/ruby-modules/bundler/default.nix b/nixpkgs/pkgs/development/ruby-modules/bundler/default.nix
new file mode 100644
index 000000000000..decde250ac23
--- /dev/null
+++ b/nixpkgs/pkgs/development/ruby-modules/bundler/default.nix
@@ -0,0 +1,14 @@
+{ buildRubyGem, ruby }:
+
+buildRubyGem rec {
+  inherit ruby;
+  name = "${gemName}-${version}";
+  gemName = "bundler";
+  version = "1.17.2";
+  source.sha256 = "0dbnq6703mjvgsri45vaw7b4wjqr89z1h8xkzsacqcp24a706m5r";
+  dontPatchShebangs = true;
+
+  postFixup = ''
+    sed -i -e "s/activate_bin_path/bin_path/g" $out/bin/bundle
+  '';
+}
diff --git a/nixpkgs/pkgs/development/ruby-modules/gem-config/default.nix b/nixpkgs/pkgs/development/ruby-modules/gem-config/default.nix
new file mode 100644
index 000000000000..7fdf5c839013
--- /dev/null
+++ b/nixpkgs/pkgs/development/ruby-modules/gem-config/default.nix
@@ -0,0 +1,438 @@
+# The standard set of gems in nixpkgs including potential fixes.
+#
+# The gemset is derived from two points of entry:
+# - An attrset describing a gem, including version, source and dependencies
+#   This is just meta data, most probably automatically generated by a tool
+#   like Bundix (https://github.com/aflatter/bundix).
+#   {
+#     name = "bundler";
+#     version = "1.6.5";
+#     sha256 = "1s4x0f5by9xs2y24jk6krq5ky7ffkzmxgr4z1nhdykdmpsi2zd0l";
+#     dependencies = [ "rake" ];
+#   }
+# - An optional derivation that may override how the gem is built. For popular
+#   gems that don't behave correctly, fixes are already provided in the form of
+#   derivations.
+#
+# This seperates "what to build" (the exact gem versions) from "how to build"
+# (to make gems behave if necessary).
+
+{ lib, fetchurl, writeScript, ruby, kerberos, libxml2, libxslt, python, stdenv, which
+, libiconv, postgresql, v8_3_16_14, clang, sqlite, zlib, imagemagick
+, pkgconfig , ncurses, xapian_1_2_22, gpgme, utillinux, fetchpatch, tzdata, icu, libffi
+, cmake, libssh2, openssl, mysql, darwin, git, perl, pcre, gecode_3, curl
+, msgpack, qt59, libsodium, snappy, libossp_uuid, lxc, libpcap, xorg, gtk2, buildRubyGem
+, cairo, re2, rake, gobject-introspection, gdk_pixbuf, zeromq, graphicsmagick, libcxx, file
+, libselinux ? null, libsepol ? null, libvirt
+}@args:
+
+let
+  v8 = v8_3_16_14;
+
+  rainbow_rake = buildRubyGem {
+    pname = "rake";
+    gemName = "rake";
+    source.sha256 = "01j8fc9bqjnrsxbppncai05h43315vmz9fwg28qdsgcjw9ck1d7n";
+    type = "gem";
+    version = "12.0.0";
+  };
+in
+
+{
+  atk = attrs: {
+    nativeBuildInputs = [ pkgconfig ];
+    buildInputs = [ gtk2 pcre rake ];
+  };
+
+  bundler = attrs:
+    let
+      templates = "${attrs.ruby.gemPath}/gems/${attrs.gemName}-${attrs.version}/lib/bundler/templates/";
+    in {
+      # patching shebangs would fail on the templates/Executable file, so we
+      # temporarily remove the executable flag.
+      preFixup  = "chmod -x $out/${templates}/Executable";
+      postFixup = ''
+        chmod +x $out/${templates}/Executable
+
+        # Allows to load another bundler version
+        sed -i -e "s/activate_bin_path/bin_path/g" $out/bin/bundle
+      '';
+    };
+
+  cairo = attrs: {
+    nativeBuildInputs = [ pkgconfig ];
+    buildInputs = [ gtk2 pcre xorg.libpthreadstubs xorg.libXdmcp];
+  };
+
+  cairo-gobject = attrs: {
+    nativeBuildInputs = [ pkgconfig ];
+    buildInputs = [ cairo pcre xorg.libpthreadstubs xorg.libXdmcp ];
+  };
+
+  capybara-webkit = attrs: {
+    buildInputs = [ qt59.qtbase qt59.qtwebkit ] ++ stdenv.lib.optionals stdenv.isDarwin [ darwin.apple_sdk.frameworks.Cocoa ];
+    NIX_CFLAGS_COMPILE = stdenv.lib.optionalString stdenv.isDarwin "-I${libcxx}/include/c++/v1";
+  };
+
+  charlock_holmes = attrs: {
+    buildInputs = [ which icu zlib ];
+  };
+
+  curb = attrs: {
+    buildInputs = [ curl ];
+  };
+
+  curses = attrs: {
+    buildInputs = [ ncurses ];
+  };
+
+  dep-selector-libgecode = attrs: {
+    USE_SYSTEM_GECODE = true;
+    postInstall = ''
+      installPath=$(cat $out/nix-support/gem-meta/install-path)
+      sed -i $installPath/lib/dep-selector-libgecode.rb -e 's@VENDORED_GECODE_DIR =.*@VENDORED_GECODE_DIR = "${gecode_3}"@'
+    '';
+  };
+
+  ethon = attrs: {
+    dontBuild = false;
+    postPatch = ''
+      substituteInPlace lib/ethon/curls/settings.rb \
+        --replace "libcurl" "${curl.out}/lib/libcurl${stdenv.hostPlatform.extensions.sharedLibrary}"
+    '';
+  };
+
+  fog-dnsimple = attrs: {
+    postInstall = ''
+      cd $(cat $out/nix-support/gem-meta/install-path)
+      rm {$out/bin,bin,../../bin}/{setup,console}
+    '';
+  };
+
+  redis-rack = attrs: {
+    dontBuild = false;
+    preBuild = ''
+      exec 3>&1
+      output="$(gem build $gemspec | tee >(cat - >&3))"
+      exec 3>&-
+      sed -i 's!"rake".freeze!!' $gemspec
+    '';
+  };
+
+  ffi-rzmq-core = attrs: {
+    postInstall = ''
+      installPath=$(cat $out/nix-support/gem-meta/install-path)
+      sed -i $installPath/lib/ffi-rzmq-core/libzmq.rb -e 's@inside_gem =.*@inside_gem = "${zeromq}/lib"@'
+    '';
+  };
+
+  mini_magick = attrs: {
+    postInstall = ''
+      installPath=$(cat $out/nix-support/gem-meta/install-path)
+      echo -e "\nENV['PATH'] += ':${graphicsmagick}/bin'\n" >> $installPath/lib/mini_magick/configuration.rb
+    '';
+  };
+
+  do_sqlite3 = attrs: {
+    buildInputs = [ sqlite ];
+  };
+
+  eventmachine = attrs: {
+    buildInputs = [ openssl ];
+  };
+
+  ffi = attrs: {
+    nativeBuildInputs = [ pkgconfig ];
+    buildInputs = [ libffi ];
+  };
+
+  gdk_pixbuf2 = attrs: {
+    nativeBuildInputs = [ pkgconfig ];
+    buildInputs = [ rake gdk_pixbuf ];
+  };
+
+  gpgme = attrs: {
+    buildInputs = [ gpgme ];
+  };
+
+  gio2 = attrs: {
+    nativeBuildInputs = [ pkgconfig ];
+    buildInputs = [ gtk2 pcre gobject-introspection ] ++ lib.optionals stdenv.isLinux [ utillinux libselinux libsepol ];
+  };
+
+  gitlab-markup = attrs: { meta.priority = 1; };
+
+  glib2 = attrs: {
+    nativeBuildInputs = [ pkgconfig ];
+    buildInputs = [ gtk2 pcre ];
+  };
+
+  gtk2 = attrs: {
+    nativeBuildInputs = [ pkgconfig ] ++ lib.optionals stdenv.isLinux [ utillinux libselinux libsepol ];
+    buildInputs = [ gtk2 pcre xorg.libpthreadstubs xorg.libXdmcp];
+    # CFLAGS must be set for this gem to detect gdkkeysyms.h correctly
+    CFLAGS = "-I${gtk2.dev}/include/gtk-2.0 -I/non-existent-path";
+  };
+
+  gobject-introspection = attrs: {
+    nativeBuildInputs = [ pkgconfig ];
+    buildInputs = [ gobject-introspection gtk2 pcre ];
+  };
+
+  grpc = attrs: {
+    nativeBuildInputs = [ pkgconfig ];
+    buildInputs = [ openssl ];
+    hardeningDisable = [ "format" ];
+    NIX_CFLAGS_COMPILE = [ "-Wno-error=stringop-overflow" "-Wno-error=implicit-fallthrough" ];
+  };
+
+  hitimes = attrs: {
+    buildInputs =
+      stdenv.lib.optionals stdenv.isDarwin
+        [ darwin.apple_sdk.frameworks.CoreServices ];
+  };
+
+  iconv = attrs: {
+    buildFlags = lib.optional stdenv.isDarwin "--with-iconv-dir=${libiconv}";
+  };
+
+  # disable bundle install as it can't install anything in addition to what is
+  # specified in pkgs/applications/misc/jekyll/Gemfile anyway. Also do chmod_R
+  # to compensate for read-only files in site_template in nix store.
+  jekyll = attrs: {
+    postInstall = ''
+      installPath=$(cat $out/nix-support/gem-meta/install-path)
+      sed -i $installPath/lib/jekyll/commands/new.rb \
+          -e 's@Exec.run("bundle", "install"@Exec.run("true"@' \
+          -e 's@FileUtils.cp_r site_template + "/.", path@FileUtils.cp_r site_template + "/.", path; FileUtils.chmod_R "u+w", path@'
+    '';
+  };
+
+  # note that you need version >= v3.16.14.8,
+  # otherwise the gem will fail to link to the libv8 binary.
+  # see: https://github.com/cowboyd/libv8/pull/161
+  libv8 = attrs: {
+    buildInputs = [ which v8 python ];
+    buildFlags = [ "--with-system-v8=true" ];
+  };
+
+  libxml-ruby = attrs: {
+    buildFlags = [
+      "--with-xml2-lib=${libxml2.out}/lib"
+      "--with-xml2-include=${libxml2.dev}/include/libxml2"
+    ];
+  };
+
+  magic = attrs: {
+    buildInputs = [ file ];
+    postInstall = ''
+      installPath=$(cat $out/nix-support/gem-meta/install-path)
+      sed -e 's@ENV\["MAGIC_LIB"\] ||@ENV\["MAGIC_LIB"\] || "${file}/lib/libmagic.so" ||@' -i $installPath/lib/magic/api.rb
+    '';
+  };
+
+  metasploit-framework = attrs: {
+    preInstall = ''
+      export HOME=$TMPDIR
+    '';
+  };
+
+  msgpack = attrs: {
+    buildInputs = [ msgpack ];
+  };
+
+  mysql = attrs: {
+    buildInputs = [ mysql.connector-c zlib openssl ];
+  };
+
+  mysql2 = attrs: {
+    buildInputs = [ mysql.connector-c zlib openssl ];
+  };
+
+  ncursesw = attrs: {
+    buildInputs = [ ncurses ];
+    buildFlags = [
+      "--with-cflags=-I${ncurses.dev}/include"
+      "--with-ldflags=-L${ncurses.out}/lib"
+    ];
+  };
+
+  nokogiri = attrs: {
+    buildFlags = [
+      "--use-system-libraries"
+      "--with-zlib-dir=${zlib.dev}"
+      "--with-xml2-lib=${libxml2.out}/lib"
+      "--with-xml2-include=${libxml2.dev}/include/libxml2"
+      "--with-xslt-lib=${libxslt.out}/lib"
+      "--with-xslt-include=${libxslt.dev}/include"
+      "--with-exslt-lib=${libxslt.out}/lib"
+      "--with-exslt-include=${libxslt.dev}/include"
+    ] ++ lib.optional stdenv.isDarwin "--with-iconv-dir=${libiconv}";
+  };
+
+  pango = attrs: {
+    nativeBuildInputs = [ pkgconfig ];
+    buildInputs = [ gtk2 xorg.libXdmcp pcre xorg.libpthreadstubs ];
+  };
+
+  patron = attrs: {
+    buildInputs = [ curl ];
+  };
+
+  pcaprub = attrs: {
+    buildInputs = [ libpcap ];
+  };
+
+  pg = attrs: {
+    buildFlags = [
+      "--with-pg-config=${postgresql}/bin/pg_config"
+    ];
+  };
+
+  puma = attrs: {
+    buildInputs = [ openssl ];
+  };
+
+  rainbow = attrs: {
+    buildInputs = [ rainbow_rake ];
+  };
+
+  rbnacl = spec: {
+    postInstall = ''
+    sed -i $(cat $out/nix-support/gem-meta/install-path)/lib/rbnacl.rb -e "2a \
+    RBNACL_LIBSODIUM_GEM_LIB_PATH = '${libsodium.out}/lib/libsodium${stdenv.hostPlatform.extensions.sharedLibrary}'
+    "
+    '';
+  };
+
+  re2 = attrs: {
+    buildInputs = [ re2 ];
+  };
+
+  rmagick = attrs: {
+    nativeBuildInputs = [ pkgconfig ];
+    buildInputs = [ imagemagick which ];
+  };
+
+  ruby-libvirt = attrs: {
+    buildInputs = [ libvirt pkgconfig ];
+    buildFlags = [
+      "--with-libvirt-include=${libvirt}/include"
+      "--with-libvirt-lib=${libvirt}/lib"
+    ];
+  };
+
+  ruby-lxc = attrs: {
+    buildInputs = [ lxc ];
+  };
+
+  ruby-terminfo = attrs: {
+    buildInputs = [ ncurses ];
+    buildFlags = [
+      "--with-cflags=-I${ncurses.dev}/include"
+      "--with-ldflags=-L${ncurses.out}/lib"
+    ];
+  };
+  rugged = attrs: {
+    nativeBuildInputs = [ pkgconfig ];
+    buildInputs = [ cmake openssl libssh2 zlib ];
+    dontUseCmakeConfigure = true;
+  };
+
+  sassc = attrs: {
+    nativeBuildInputs = [ rake ];
+  };
+
+  scrypt = attrs:
+    if stdenv.isDarwin then {
+      dontBuild = false;
+      postPatch = ''
+        sed -i -e "s/-arch i386//" Rakefile ext/scrypt/Rakefile
+      '';
+    } else {};
+
+  sequel_pg = attrs: {
+    buildInputs = [ postgresql ];
+  };
+
+  snappy = attrs: {
+    buildInputs = [ args.snappy ];
+  };
+
+  sqlite3 = attrs: {
+    buildFlags = [
+      "--with-sqlite3-include=${sqlite.dev}/include"
+      "--with-sqlite3-lib=${sqlite.out}/lib"
+    ];
+  };
+
+  sup = attrs: {
+    dontBuild = false;
+    # prevent sup from trying to dynamically install `xapian-ruby`.
+    postPatch = ''
+      cp ${./mkrf_conf_xapian.rb} ext/mkrf_conf_xapian.rb
+
+      substituteInPlace lib/sup/crypto.rb \
+        --replace 'which gpg2' \
+                  '${which}/bin/which gpg'
+    '';
+  };
+
+  rb-readline = attrs: {
+    dontBuild = false;
+    postPatch = ''
+      substituteInPlace lib/rbreadline.rb \
+        --replace 'infocmp' '${ncurses.dev}/bin/infocmp'
+    '';
+  };
+
+  timfel-krb5-auth = attrs: {
+    buildInputs = [ kerberos ];
+  };
+
+  tiny_tds = attrs: {
+    nativeBuildInputs = [ pkgconfig openssl ];
+  };
+
+  therubyracer = attrs: {
+    buildFlags = [
+      "--with-v8-dir=${v8}"
+      "--with-v8-include=${v8}/include"
+      "--with-v8-lib=${v8}/lib"
+    ];
+  };
+
+  typhoeus = attrs: {
+    buildInputs = [ curl ];
+  };
+
+  tzinfo = attrs: lib.optionalAttrs (lib.versionAtLeast attrs.version "1.0") {
+    dontBuild = false;
+    postPatch = ''
+      substituteInPlace lib/tzinfo/zoneinfo_data_source.rb \
+        --replace "/usr/share/zoneinfo" "${tzdata}/share/zoneinfo"
+    '';
+  };
+
+  uuid4r = attrs: {
+    buildInputs = [ which libossp_uuid ];
+  };
+
+  xapian-ruby = attrs: {
+    # use the system xapian
+    dontBuild = false;
+    nativeBuildInputs = [ pkgconfig ];
+    buildInputs = [ xapian_1_2_22 zlib ];
+    postPatch = ''
+      cp ${./xapian-Rakefile} Rakefile
+    '';
+    preInstall = ''
+      export XAPIAN_CONFIG=${xapian_1_2_22}/bin/xapian-config
+    '';
+  };
+
+   zookeeper = attrs: {
+     buildInputs = stdenv.lib.optionals stdenv.isDarwin [ darwin.cctools ];
+   };
+
+}
diff --git a/nixpkgs/pkgs/development/ruby-modules/gem-config/mkrf_conf_xapian.rb b/nixpkgs/pkgs/development/ruby-modules/gem-config/mkrf_conf_xapian.rb
new file mode 100644
index 000000000000..e19f06e23ac2
--- /dev/null
+++ b/nixpkgs/pkgs/development/ruby-modules/gem-config/mkrf_conf_xapian.rb
@@ -0,0 +1,14 @@
+require 'rubygems'
+require 'rubygems/command.rb'
+require 'rubygems/dependency_installer.rb'
+require 'rbconfig'
+
+begin
+  Gem::Command.build_args = ARGV
+rescue NoMethodError
+end
+
+# create dummy rakefile to indicate success
+f = File.open(File.join(File.dirname(__FILE__), "Rakefile"), "w")
+f.write("task :default\n")
+f.close
diff --git a/nixpkgs/pkgs/development/ruby-modules/gem-config/xapian-Rakefile b/nixpkgs/pkgs/development/ruby-modules/gem-config/xapian-Rakefile
new file mode 100644
index 000000000000..9f0b8e72f08c
--- /dev/null
+++ b/nixpkgs/pkgs/development/ruby-modules/gem-config/xapian-Rakefile
@@ -0,0 +1,38 @@
+# encoding: utf-8
+# Install the xapian binaries into the lib folder of the gem
+require 'rbconfig'
+
+c = RbConfig::CONFIG
+
+def system!(cmd)
+  puts cmd
+  system(cmd) or raise
+end
+
+source_dir = 'xapian_source'
+bindings = Dir["#{source_dir}/xapian-bindings-*"].first
+bindings = File.basename(bindings, ".tar.xz")
+
+task :default do
+  system! "tar -xJf #{source_dir}/#{bindings}.tar.xz"
+
+  prefix = Dir.pwd
+  ENV['LDFLAGS'] = "-L#{prefix}/lib"
+
+  system! "mkdir -p lib"
+
+  Dir.chdir bindings do
+    ENV['RUBY'] ||= "#{c['bindir']}/#{c['RUBY_INSTALL_NAME']}"
+    system! "./configure --prefix=#{prefix} --exec-prefix=#{prefix} --with-ruby"
+    system! "make clean all"
+  end
+
+  system! "cp -r #{bindings}/ruby/.libs/_xapian.* lib"
+  system! "cp #{bindings}/ruby/xapian.rb lib"
+
+  system! "rm lib/*.la"
+  system! "rm lib/*.lai"
+
+  system! "rm -R #{bindings}"
+  system! "rm -R #{source_dir}"
+end
diff --git a/nixpkgs/pkgs/development/ruby-modules/gem/default.nix b/nixpkgs/pkgs/development/ruby-modules/gem/default.nix
new file mode 100644
index 000000000000..b0abb2c54fc5
--- /dev/null
+++ b/nixpkgs/pkgs/development/ruby-modules/gem/default.nix
@@ -0,0 +1,228 @@
+# This builds gems in a way that is compatible with bundler.
+#
+# Bundler installs gems from git sources _very_ differently from how RubyGems
+# installes gem packages, though they both install gem packages similarly.
+#
+# We monkey-patch Bundler to remove any impurities and then drive its internals
+# to install git gems.
+#
+# For the sake of simplicity, gem packages are installed with the standard `gem`
+# program.
+#
+# Note that bundler does not support multiple prefixes; it assumes that all
+# gems are installed in a common prefix, and has no support for specifying
+# otherwise. Therefore, if you want to be able to use the resulting derivations
+# with bundler, you need to create a symlink forrest first, which is what
+# `bundlerEnv` does for you.
+#
+# Normal gem packages can be used outside of bundler; a binstub is created in
+# $out/bin.
+
+{ lib, fetchurl, fetchgit, makeWrapper, git, darwin
+, ruby, bundler
+} @ defs:
+
+lib.makeOverridable (
+
+{ name ? null
+, gemName
+, version ? null
+, type ? "gem"
+, document ? [] # e.g. [ "ri" "rdoc" ]
+, platform ? "ruby"
+, ruby ? defs.ruby
+, stdenv ? ruby.stdenv
+, namePrefix ? (let
+    rubyName = builtins.parseDrvName ruby.name;
+  in "${rubyName.name}${rubyName.version}-")
+, buildInputs ? []
+, meta ? {}
+, patches ? []
+, gemPath ? []
+, dontStrip ? true
+# Assume we don't have to build unless strictly necessary (e.g. the source is a
+# git checkout).
+# If you need to apply patches, make sure to set `dontBuild = false`;
+, dontBuild ? true
+, dontInstallManpages ? false
+, propagatedBuildInputs ? []
+, propagatedUserEnvPkgs ? []
+, buildFlags ? []
+, passthru ? {}
+, ...} @ attrs:
+
+let
+  src = attrs.src or (
+    if type == "gem" then
+      fetchurl {
+        urls = map (
+          remote: "${remote}/gems/${gemName}-${version}.gem"
+        ) (attrs.source.remotes or [ "https://rubygems.org" ]);
+        inherit (attrs.source) sha256;
+      }
+    else if type == "git" then
+      fetchgit {
+        inherit (attrs.source) url rev sha256 fetchSubmodules;
+        leaveDotGit = true;
+      }
+    else if type == "url" then
+      fetchurl attrs.source
+    else
+      throw "buildRubyGem: don't know how to build a gem of type \"${type}\""
+  );
+  documentFlag =
+    if document == []
+    then "-N"
+    else "--document ${lib.concatStringsSep "," document}";
+
+in
+
+stdenv.mkDerivation ((builtins.removeAttrs attrs ["source"]) // {
+  inherit ruby;
+  inherit dontBuild;
+  inherit dontStrip;
+  inherit type;
+
+  buildInputs = [
+    ruby makeWrapper
+  ] ++ lib.optionals (type == "git") [ git ]
+    ++ lib.optionals (type != "gem") [ bundler ]
+    ++ lib.optional stdenv.isDarwin darwin.libobjc
+    ++ buildInputs;
+
+  #name = builtins.trace (attrs.name or "no attr.name" ) "${namePrefix}${gemName}-${version}";
+  name = attrs.name or "${namePrefix}${gemName}-${version}";
+
+  inherit src;
+
+  unpackPhase = attrs.unpackPhase or ''
+    runHook preUnpack
+
+    if [[ -f $src && $src == *.gem ]]; then
+      if [[ -z "$dontBuild" ]]; then
+        # we won't know the name of the directory that RubyGems creates,
+        # so we'll just use a glob to find it and move it over.
+        gempkg="$src"
+        sourceRoot=source
+        gem unpack $gempkg --target=container
+        cp -r container/* $sourceRoot
+        rm -r container
+
+        # copy out the original gemspec, for convenience during patching /
+        # overrides.
+        gem specification $gempkg  --ruby > original.gemspec
+        gemspec=$(readlink -f .)/original.gemspec
+      else
+        gempkg="$src"
+      fi
+    else
+      # Fall back to the original thing for everything else.
+      dontBuild=""
+      preUnpack="" postUnpack="" unpackPhase
+    fi
+
+    runHook postUnpack
+  '';
+
+  buildPhase = attrs.buildPhase or ''
+    runHook preBuild
+
+    if [[ "$type" == "gem" ]]; then
+      if [[ -z "$gemspec" ]]; then
+        gemspec="$(find . -name '*.gemspec')"
+        echo "found the following gemspecs:"
+        echo "$gemspec"
+        gemspec="$(echo "$gemspec" | head -n1)"
+      fi
+
+      exec 3>&1
+      output="$(gem build $gemspec | tee >(cat - >&3))"
+      exec 3>&-
+
+      gempkg=$(echo "$output" | grep -oP 'File: \K(.*)')
+
+      echo "gem package built: $gempkg"
+    fi
+
+    runHook postBuild
+  '';
+
+  # Note:
+  #   We really do need to keep the $out/${ruby.gemPath}/cache.
+  #   This is very important in order for many parts of RubyGems/Bundler to not blow up.
+  #   See https://github.com/bundler/bundler/issues/3327
+  installPhase = attrs.installPhase or ''
+    runHook preInstall
+
+    export GEM_HOME=$out/${ruby.gemPath}
+    mkdir -p $GEM_HOME
+
+    echo "buildFlags: $buildFlags"
+
+    ${lib.optionalString (type ==  "url") ''
+    ruby ${./nix-bundle-install.rb} \
+      "path" \
+      '${gemName}' \
+      '${version}' \
+      '${lib.escapeShellArgs buildFlags}'
+    ''}
+    ${lib.optionalString (type == "git") ''
+    ruby ${./nix-bundle-install.rb} \
+      "git" \
+      '${gemName}' \
+      '${version}' \
+      '${lib.escapeShellArgs buildFlags}' \
+      '${attrs.source.url}' \
+      '${src}' \
+      '${attrs.source.rev}'
+    ''}
+
+    ${lib.optionalString (type == "gem") ''
+    if [[ -z "$gempkg" ]]; then
+      echo "failure: \$gempkg path unspecified" 1>&2
+      exit 1
+    elif [[ ! -f "$gempkg" ]]; then
+      echo "failure: \$gempkg path invalid" 1>&2
+      exit 1
+    fi
+
+    gem install \
+      --local \
+      --force \
+      --http-proxy 'http://nodtd.invalid' \
+      --ignore-dependencies \
+      --install-dir "$GEM_HOME" \
+      --build-root '/' \
+      --backtrace \
+      --no-env-shebang \
+      ${documentFlag} \
+      $gempkg $gemFlags -- $buildFlags
+
+    # looks like useless files which break build repeatability and consume space
+    rm -fv $out/${ruby.gemPath}/doc/*/*/created.rid || true
+    rm -fv $out/${ruby.gemPath}/gems/*/ext/*/mkmf.log || true
+
+    # write out metadata and binstubs
+    spec=$(echo $out/${ruby.gemPath}/specifications/*.gemspec)
+    ruby ${./gem-post-build.rb} "$spec"
+    ''}
+
+    ${lib.optionalString (!dontInstallManpages) ''
+    for section in {1..9}; do
+      mandir="$out/share/man/man$section"
+      find $out/lib \( -wholename "*/man/*.$section" -o -wholename "*/man/man$section/*.$section" \) \
+        -execdir mkdir -p $mandir \; -execdir cp '{}' $mandir \;
+    done
+    ''}
+
+    runHook postInstall
+  '';
+
+  propagatedBuildInputs = gemPath ++ propagatedBuildInputs;
+  propagatedUserEnvPkgs = gemPath ++ propagatedUserEnvPkgs;
+
+  passthru = passthru // { isRubyGem = true; };
+  inherit meta;
+})
+
+)
diff --git a/nixpkgs/pkgs/development/ruby-modules/gem/gem-post-build.rb b/nixpkgs/pkgs/development/ruby-modules/gem/gem-post-build.rb
new file mode 100644
index 000000000000..f0322b67f61f
--- /dev/null
+++ b/nixpkgs/pkgs/development/ruby-modules/gem/gem-post-build.rb
@@ -0,0 +1,81 @@
+require 'rbconfig'
+require 'rubygems'
+require 'rubygems/specification'
+require 'fileutils'
+
+ruby = File.join(ENV["ruby"], "bin", RbConfig::CONFIG['ruby_install_name'])
+out = ENV["out"]
+bin_path = File.join(ENV["out"], "bin")
+gem_home = ENV["GEM_HOME"]
+gem_path = ENV["GEM_PATH"].split(File::PATH_SEPARATOR)
+install_path = Dir.glob("#{gem_home}/gems/*").first
+gemspec_path = ARGV[0]
+
+if defined?(Encoding.default_internal)
+  Encoding.default_internal = Encoding::UTF_8
+  Encoding.default_external = Encoding::UTF_8
+end
+
+gemspec_content = File.read(gemspec_path)
+spec = nil
+if gemspec_content[0..2] == "---" # YAML header
+  spec = Gem::Specification.from_yaml(gemspec_content)
+else
+  spec = Gem::Specification.load(gemspec_path)
+end
+
+FileUtils.mkdir_p("#{out}/nix-support")
+
+# write meta-data
+meta = "#{out}/nix-support/gem-meta"
+FileUtils.mkdir_p(meta)
+FileUtils.ln_s(gemspec_path, "#{meta}/spec")
+File.open("#{meta}/name", "w") do |f|
+  f.write(spec.name)
+end
+File.open("#{meta}/install-path", "w") do |f|
+  f.write(install_path)
+end
+File.open("#{meta}/require-paths", "w") do |f|
+  f.write(spec.require_paths.join(" "))
+end
+File.open("#{meta}/executables", "w") do |f|
+  f.write(spec.executables.join(" "))
+end
+
+# add this gem to the GEM_PATH for dependencies
+File.open("#{out}/nix-support/setup-hook", "a") do |f|
+  f.puts("addToSearchPath GEM_PATH #{gem_home}")
+  spec.require_paths.each do |dir|
+    f.puts("addToSearchPath RUBYLIB #{install_path}/#{dir}")
+  end
+end
+
+# create regular rubygems binstubs
+FileUtils.mkdir_p(bin_path)
+spec.executables.each do |exe|
+  File.open("#{bin_path}/#{exe}", "w") do |f|
+    f.write(<<-EOF)
+#!#{ruby}
+#
+# This file was generated by Nix.
+#
+# The application '#{exe}' is installed as part of a gem, and
+# this file is here to facilitate running it.
+#
+
+require 'rubygems'
+
+Gem.paths = {
+  'GEM_PATH' => (
+    ENV['GEM_PATH'].to_s.split(File::PATH_SEPARATOR) +
+    #{([gem_home] + gem_path).to_s}
+  ).join(File::PATH_SEPARATOR)
+}
+
+load Gem.activate_bin_path(#{spec.name.inspect}, #{exe.inspect}, #{spec.version.to_s.inspect})
+    EOF
+  end
+
+  FileUtils.chmod("+x", "#{bin_path}/#{exe}")
+end
diff --git a/nixpkgs/pkgs/development/ruby-modules/gem/nix-bundle-install.rb b/nixpkgs/pkgs/development/ruby-modules/gem/nix-bundle-install.rb
new file mode 100644
index 000000000000..142d2da9bee2
--- /dev/null
+++ b/nixpkgs/pkgs/development/ruby-modules/gem/nix-bundle-install.rb
@@ -0,0 +1,182 @@
+require 'rbconfig'
+require 'bundler/vendored_thor'
+require 'bundler'
+require 'rubygems/command'
+require 'fileutils'
+require 'pathname'
+require 'tmpdir'
+
+if defined?(Encoding.default_internal)
+  Encoding.default_internal = Encoding::UTF_8
+  Encoding.default_external = Encoding::UTF_8
+end
+
+# Options:
+#
+#   type        - installation type, either "git" or "path"
+#   name        - the gem name
+#   version     - gem version
+#   build-flags - build arguments
+#
+# Git-only options:
+#
+#   uri         - git repo uri
+#   repo        - path to local checkout
+#   ref         - the commit hash
+
+ruby = File.join(ENV["ruby"], "bin", RbConfig::CONFIG['ruby_install_name'])
+out = ENV["out"]
+bin_dir = File.join(ENV["out"], "bin")
+
+type        = ARGV[0]
+name        = ARGV[1]
+version     = ARGV[2]
+build_flags = ARGV[3]
+if type == "git"
+  uri         = ARGV[4]
+  REPO        = ARGV[5]
+  ref         = ARGV[6]
+end
+
+# options to pass to bundler
+options = {
+  "name" => name,
+  "version" => version,
+}
+if type == "path"
+  options.merge!({
+    "path" => Dir.pwd,
+  })
+elsif type == "git"
+  options.merge!({
+    "uri"  => uri,
+    "ref"  => ref,
+  })
+end
+
+# Monkey-patch Bundler to use our local checkout.
+# I wish we didn't have to do this, but bundler does not expose an API to do
+# these kinds of things.
+Bundler.module_eval do
+  def self.requires_sudo?
+    false
+  end
+
+  def self.root
+    # we don't have a Gemfile, so it doesn't make sense to try to make paths
+    # relative to the (non existent) parent directory thereof, so we give a
+    # nonsense path here.
+    Pathname.new("/no-root-path")
+  end
+
+  def self.bundle_path
+    Pathname.new(ENV["GEM_HOME"])
+  end
+
+  def self.locked_gems
+    nil
+  end
+end
+
+if type == "git"
+  Bundler::Source::Git.class_eval do
+    def allow_git_ops?
+      true
+    end
+  end
+
+  Bundler::Source::Git::GitProxy.class_eval do
+    def checkout
+      unless path.exist?
+        FileUtils.mkdir_p(path.dirname)
+        FileUtils.cp_r(File.join(REPO, ".git"), path)
+        system("chmod -R +w #{path}")
+      end
+    end
+
+    def copy_to(destination, submodules=false)
+      unless File.exist?(destination.join(".git"))
+        FileUtils.mkdir_p(destination.dirname)
+        FileUtils.cp_r(REPO, destination)
+        system("chmod -R +w #{destination}")
+      end
+    end
+  end
+end
+
+# UI
+verbose = false
+no_color = false
+Bundler.ui = Bundler::UI::Shell.new({"no-color" => no_color})
+Bundler.ui.level = "debug" if verbose
+
+# Install
+if type == "git"
+  source = Bundler::Source::Git.new(options)
+else
+  source = Bundler::Source::Path.new(options)
+end
+spec = source.specs.search_all(name).first
+Bundler.rubygems.with_build_args [build_flags] do
+  source.install(spec)
+end
+
+msg = spec.post_install_message
+if msg
+  Bundler.ui.confirm "Post-install message from #{name}:"
+  Bundler.ui.info msg
+end
+
+# Write out the binstubs
+if spec.executables.any?
+  FileUtils.mkdir_p(bin_dir)
+  spec.executables.each do |exe|
+    wrapper = File.join(bin_dir, exe)
+    File.open(wrapper, "w") do |f|
+      f.write(<<-EOF)
+#!#{ruby}
+#
+# This file was generated by Nix.
+#
+# The application '#{exe}' is installed as part of a gem, and
+# this file is here to facilitate running it.
+#
+
+require 'rubygems'
+require 'bundler/setup'
+
+load Gem.bin_path(#{spec.name.inspect}, #{exe.inspect})
+EOF
+    end
+
+    FileUtils.chmod("+x", wrapper)
+  end
+end
+
+# Write out metadata
+meta = "#{out}/nix-support/gem-meta"
+FileUtils.mkdir_p(meta)
+FileUtils.ln_s(spec.loaded_from.to_s, "#{meta}/spec")
+File.open("#{meta}/name", "w") do |f|
+  f.write spec.name
+end
+if type == "git"
+  File.open("#{meta}/install-path", "w") do |f|
+    f.write source.install_path.to_s
+  end
+end
+File.open("#{meta}/require-paths", "w") do |f|
+  f.write spec.require_paths.join(" ")
+end
+File.open("#{meta}/executables", "w") do |f|
+  f.write spec.executables.join(" ")
+end
+
+# make the lib available during bundler/git installs
+if type == "git"
+  File.open("#{out}/nix-support/setup-hook", "a") do |f|
+    spec.require_paths.each do |dir|
+      f.puts("addToSearchPath RUBYLIB #{source.install_path}/#{dir}")
+    end
+  end
+end
diff --git a/nixpkgs/pkgs/development/ruby-modules/runtests.sh b/nixpkgs/pkgs/development/ruby-modules/runtests.sh
new file mode 100755
index 000000000000..8bb8c8a5462c
--- /dev/null
+++ b/nixpkgs/pkgs/development/ruby-modules/runtests.sh
@@ -0,0 +1,6 @@
+#!/usr/bin/env bash
+set -o xtrace
+cd $(dirname $0)
+find . -name text.nix
+testfiles=$(find . -name test.nix)
+nix-build -E "with import <nixpkgs> {}; callPackage testing/driver.nix { testFiles = [ $testfiles ]; }" --show-trace && cat result
diff --git a/nixpkgs/pkgs/development/ruby-modules/solargraph/Gemfile b/nixpkgs/pkgs/development/ruby-modules/solargraph/Gemfile
new file mode 100644
index 000000000000..fa41b7c1d216
--- /dev/null
+++ b/nixpkgs/pkgs/development/ruby-modules/solargraph/Gemfile
@@ -0,0 +1,3 @@
+source 'https://rubygems.org' do
+  gem 'solargraph'
+end
diff --git a/nixpkgs/pkgs/development/ruby-modules/solargraph/Gemfile.lock b/nixpkgs/pkgs/development/ruby-modules/solargraph/Gemfile.lock
new file mode 100644
index 000000000000..a936dd25d925
--- /dev/null
+++ b/nixpkgs/pkgs/development/ruby-modules/solargraph/Gemfile.lock
@@ -0,0 +1,50 @@
+GEM
+  remote: https://rubygems.org/
+  specs:
+    ast (2.4.0)
+    eventmachine (1.2.7)
+    htmlentities (4.3.4)
+    jaro_winkler (1.5.1)
+    kramdown (1.17.0)
+    mini_portile2 (2.3.0)
+    nokogiri (1.8.5)
+      mini_portile2 (~> 2.3.0)
+    parallel (1.12.1)
+    parser (2.5.3.0)
+      ast (~> 2.4.0)
+    powerpack (0.1.2)
+    rainbow (3.0.0)
+    reverse_markdown (1.1.0)
+      nokogiri
+    rubocop (0.60.0)
+      jaro_winkler (~> 1.5.1)
+      parallel (~> 1.10)
+      parser (>= 2.5, != 2.5.1.1)
+      powerpack (~> 0.1)
+      rainbow (>= 2.2.2, < 4.0)
+      ruby-progressbar (~> 1.7)
+      unicode-display_width (~> 1.4.0)
+    ruby-progressbar (1.10.0)
+    solargraph (0.29.1)
+      eventmachine (~> 1.2, >= 1.2.5)
+      htmlentities (~> 4.3, >= 4.3.4)
+      kramdown (~> 1.16)
+      parser (~> 2.3)
+      reverse_markdown (~> 1.0, >= 1.0.5)
+      rubocop (~> 0.52)
+      thor (~> 0.19, >= 0.19.4)
+      tilt (~> 2.0)
+      yard (~> 0.9)
+    thor (0.20.3)
+    tilt (2.0.9)
+    unicode-display_width (1.4.0)
+    yard (0.9.16)
+
+PLATFORMS
+  ruby
+
+DEPENDENCIES
+  solargraph!
+
+BUNDLED WITH
+   1.17.1
diff --git a/nixpkgs/pkgs/development/ruby-modules/solargraph/default.nix b/nixpkgs/pkgs/development/ruby-modules/solargraph/default.nix
new file mode 100644
index 000000000000..2f60dacd358b
--- /dev/null
+++ b/nixpkgs/pkgs/development/ruby-modules/solargraph/default.nix
@@ -0,0 +1,15 @@
+{ lib, bundlerApp }:
+
+bundlerApp rec {
+  pname = "solargraph";
+  exes = ["solargraph"  "solargraph-runtime"];
+  gemdir = ./.;
+
+  meta = with lib; {
+    description = "IDE tools for the Ruby language";
+    homepage = http://www.github.com/castwide/solargraph;
+    license = licenses.mit;
+    maintainers = with maintainers; [ worldofpeace ];
+    platforms = platforms.unix;
+  };
+}
diff --git a/nixpkgs/pkgs/development/ruby-modules/solargraph/gemset.nix b/nixpkgs/pkgs/development/ruby-modules/solargraph/gemset.nix
new file mode 100644
index 000000000000..bfb5496444af
--- /dev/null
+++ b/nixpkgs/pkgs/development/ruby-modules/solargraph/gemset.nix
@@ -0,0 +1,159 @@
+{
+  ast = {
+    source = {
+      remotes = ["https://rubygems.org"];
+      sha256 = "184ssy3w93nkajlz2c70ifm79jp3j737294kbc5fjw69v1w0n9x7";
+      type = "gem";
+    };
+    version = "2.4.0";
+  };
+  eventmachine = {
+    source = {
+      remotes = ["https://rubygems.org"];
+      sha256 = "0wh9aqb0skz80fhfn66lbpr4f86ya2z5rx6gm5xlfhd05bj1ch4r";
+      type = "gem";
+    };
+    version = "1.2.7";
+  };
+  htmlentities = {
+    source = {
+      remotes = ["https://rubygems.org"];
+      sha256 = "1nkklqsn8ir8wizzlakncfv42i32wc0w9hxp00hvdlgjr7376nhj";
+      type = "gem";
+    };
+    version = "4.3.4";
+  };
+  jaro_winkler = {
+    source = {
+      remotes = ["https://rubygems.org"];
+      sha256 = "0rr797nqz081bfk30m2apj5h24bg5d1jr1c8p3xwx4hbwsrbclah";
+      type = "gem";
+    };
+    version = "1.5.1";
+  };
+  kramdown = {
+    source = {
+      remotes = ["https://rubygems.org"];
+      sha256 = "1n1c4jmrh5ig8iv1rw81s4mw4xsp4v97hvf8zkigv4hn5h542qjq";
+      type = "gem";
+    };
+    version = "1.17.0";
+  };
+  mini_portile2 = {
+    source = {
+      remotes = ["https://rubygems.org"];
+      sha256 = "13d32jjadpjj6d2wdhkfpsmy68zjx90p49bgf8f7nkpz86r1fr11";
+      type = "gem";
+    };
+    version = "2.3.0";
+  };
+  nokogiri = {
+    dependencies = ["mini_portile2"];
+    source = {
+      remotes = ["https://rubygems.org"];
+      sha256 = "0byyxrazkfm29ypcx5q4syrv126nvjnf7z6bqi01sqkv4llsi4qz";
+      type = "gem";
+    };
+    version = "1.8.5";
+  };
+  parallel = {
+    source = {
+      remotes = ["https://rubygems.org"];
+      sha256 = "01hj8v1qnyl5ndrs33g8ld8ibk0rbcqdpkpznr04gkbxd11pqn67";
+      type = "gem";
+    };
+    version = "1.12.1";
+  };
+  parser = {
+    dependencies = ["ast"];
+    source = {
+      remotes = ["https://rubygems.org"];
+      sha256 = "1zjk0w1kjj3xk8ymy1430aa4gg0k8ckphfj88br6il4pm83f0n1f";
+      type = "gem";
+    };
+    version = "2.5.3.0";
+  };
+  powerpack = {
+    source = {
+      remotes = ["https://rubygems.org"];
+      sha256 = "1r51d67wd467rpdfl6x43y84vwm8f5ql9l9m85ak1s2sp3nc5hyv";
+      type = "gem";
+    };
+    version = "0.1.2";
+  };
+  rainbow = {
+    source = {
+      remotes = ["https://rubygems.org"];
+      sha256 = "0bb2fpjspydr6x0s8pn1pqkzmxszvkfapv0p4627mywl7ky4zkhk";
+      type = "gem";
+    };
+    version = "3.0.0";
+  };
+  reverse_markdown = {
+    dependencies = ["nokogiri"];
+    source = {
+      remotes = ["https://rubygems.org"];
+      sha256 = "0w7y5n74daajvl9gixr91nh8670d7mkgspkk3ql71m8azq3nffbg";
+      type = "gem";
+    };
+    version = "1.1.0";
+  };
+  rubocop = {
+    dependencies = ["jaro_winkler" "parallel" "parser" "powerpack" "rainbow" "ruby-progressbar" "unicode-display_width"];
+    source = {
+      remotes = ["https://rubygems.org"];
+      sha256 = "1ivk049z3mp12nc6v1wn35bsq1g7nz1i2r4xwzqf0v25hm2v7n1i";
+      type = "gem";
+    };
+    version = "0.60.0";
+  };
+  ruby-progressbar = {
+    source = {
+      remotes = ["https://rubygems.org"];
+      sha256 = "1cv2ym3rl09svw8940ny67bav7b2db4ms39i4raaqzkf59jmhglk";
+      type = "gem";
+    };
+    version = "1.10.0";
+  };
+  solargraph = {
+    dependencies = ["eventmachine" "htmlentities" "kramdown" "parser" "reverse_markdown" "rubocop" "thor" "tilt" "yard"];
+    source = {
+      remotes = ["https://rubygems.org"];
+      sha256 = "12sy1rdz2fk3aba43701qp1250xm8w26rlizypd6h5rnmmqm5q54";
+      type = "gem";
+    };
+    version = "0.29.1";
+  };
+  thor = {
+    source = {
+      remotes = ["https://rubygems.org"];
+      sha256 = "1yhrnp9x8qcy5vc7g438amd5j9sw83ih7c30dr6g6slgw9zj3g29";
+      type = "gem";
+    };
+    version = "0.20.3";
+  };
+  tilt = {
+    source = {
+      remotes = ["https://rubygems.org"];
+      sha256 = "0ca4k0clwf0rkvy7726x4nxpjxkpv67w043i39saxgldxd97zmwz";
+      type = "gem";
+    };
+    version = "2.0.9";
+  };
+  unicode-display_width = {
+    source = {
+      remotes = ["https://rubygems.org"];
+      sha256 = "0040bsdpcmvp8w31lqi2s9s4p4h031zv52401qidmh25cgyh4a57";
+      type = "gem";
+    };
+    version = "1.4.0";
+  };
+  yard = {
+    source = {
+      remotes = ["https://rubygems.org"];
+      sha256 = "0lmmr1839qgbb3zxfa7jf5mzy17yjl1yirwlgzdhws4452gqhn67";
+      type = "gem";
+    };
+    version = "0.9.16";
+  };
+}
\ No newline at end of file
diff --git a/nixpkgs/pkgs/development/ruby-modules/testing/assertions.nix b/nixpkgs/pkgs/development/ruby-modules/testing/assertions.nix
new file mode 100644
index 000000000000..f28cfcd508d4
--- /dev/null
+++ b/nixpkgs/pkgs/development/ruby-modules/testing/assertions.nix
@@ -0,0 +1,28 @@
+{ test, lib, ...}:
+{
+  equal = expected: actual:
+    if actual == expected then
+      (test.passed "= ${toString expected}") else
+      (test.failed (
+      "expected '${toString expected}'(${builtins.typeOf expected})"
+      + " !=  "+
+      "actual '${toString actual}'(${builtins.typeOf actual})"
+      ));
+
+  beASet = actual:
+    if builtins.isAttrs actual then
+      (test.passed "is a set") else
+      (test.failed "is not a set, was ${builtins.typeOf actual}: ${toString actual}");
+
+  haveKeys = expected: actual:
+    if builtins.all
+    (ex: builtins.any (ac: ex == ac) (builtins.attrNames actual))
+    expected then
+      (test.passed "has expected keys") else
+      (test.failed "keys differ: expected: [${lib.concatStringsSep ";" expected}] actual: [${lib.concatStringsSep ";" (builtins.attrNames actual)}]");
+
+  havePrefix = expected: actual:
+    if lib.hasPrefix expected actual then
+      (test.passed "has prefix '${expected}'") else
+      (test.failed "prefix '${expected}' not found in '${actual}'");
+}
diff --git a/nixpkgs/pkgs/development/ruby-modules/testing/driver.nix b/nixpkgs/pkgs/development/ruby-modules/testing/driver.nix
new file mode 100644
index 000000000000..65e7c8d4416d
--- /dev/null
+++ b/nixpkgs/pkgs/development/ruby-modules/testing/driver.nix
@@ -0,0 +1,20 @@
+/*
+Run with:
+nix-build -E 'with import <nixpkgs> { }; callPackage ./test.nix {}' --show-trace; and cat result
+
+Confusingly, the ideal result ends with something like:
+error: build of ‘/nix/store/3245f3dcl2wxjs4rci7n069zjlz8qg85-test-results.tap.drv’ failed
+*/
+{ writeText, lib, callPackage, testFiles, stdenv, ruby }@defs:
+let
+  testTools = rec {
+    test = import ./testing.nix;
+    stubs = import ./stubs.nix defs;
+    should = import ./assertions.nix { inherit test lib; };
+  };
+
+  tap = import ./tap-support.nix;
+
+  results = builtins.concatLists (map (file: callPackage file testTools) testFiles);
+in
+  writeText "test-results.tap" (tap.output results)
diff --git a/nixpkgs/pkgs/development/ruby-modules/testing/stubs.nix b/nixpkgs/pkgs/development/ruby-modules/testing/stubs.nix
new file mode 100644
index 000000000000..aaab2f689602
--- /dev/null
+++ b/nixpkgs/pkgs/development/ruby-modules/testing/stubs.nix
@@ -0,0 +1,30 @@
+{ stdenv, lib, ruby, callPackage, ... }:
+let
+  mkDerivation = {name, ...}@argSet:
+  derivation {
+    inherit name;
+    text = (builtins.toJSON (lib.filterAttrs ( n: v: builtins.any (x: x == n) ["name" "system"]) argSet));
+    builder = stdenv.shell;
+    args = [ "-c" "echo  $(<$textPath) > $out"];
+    system = stdenv.hostPlatform.system;
+    passAsFile = ["text"];
+  };
+  fetchurl = {url?"", urls ? [],...}: "fetchurl:${if urls == [] then url else builtins.head urls}";
+
+  stdenv' = stdenv // {
+    inherit mkDerivation;
+    stubbed = true;
+  };
+  ruby' = ruby // {
+    stdenv = stdenv';
+    stubbed = true;
+  };
+in
+  {
+    ruby = ruby';
+    buildRubyGem = callPackage ../gem {
+      inherit fetchurl;
+      ruby = ruby';
+    };
+    stdenv = stdenv';
+  }
diff --git a/nixpkgs/pkgs/development/ruby-modules/testing/tap-support.nix b/nixpkgs/pkgs/development/ruby-modules/testing/tap-support.nix
new file mode 100644
index 000000000000..74fcceebaa04
--- /dev/null
+++ b/nixpkgs/pkgs/development/ruby-modules/testing/tap-support.nix
@@ -0,0 +1,21 @@
+with builtins;
+let
+  withIndexes = list: genList (idx: (elemAt list idx) // {index = idx;}) (length list);
+
+  testLine = report: "${okStr report} ${toString (report.index + 1)} ${report.description}" + testDirective report + testYaml report;
+
+  # These are part of the TAP spec, not yet implemented.
+  #c.f.  https://github.com/NixOS/nixpkgs/issues/27071
+  testDirective = report: "";
+  testYaml = report: "";
+
+  okStr = { result, ...}: if result == "pass" then "ok" else "not ok";
+in
+  {
+    output = reports: ''
+      TAP version 13
+      1..${toString (length reports)}'' + (foldl' (l: r: l + "\n" + r) "" (map testLine (withIndexes reports))) + ''
+
+      # Finished at ${toString currentTime}
+      '';
+  }
diff --git a/nixpkgs/pkgs/development/ruby-modules/testing/testing.nix b/nixpkgs/pkgs/development/ruby-modules/testing/testing.nix
new file mode 100644
index 000000000000..43d10fca0444
--- /dev/null
+++ b/nixpkgs/pkgs/development/ruby-modules/testing/testing.nix
@@ -0,0 +1,62 @@
+with builtins;
+let
+  /*
+  underTest = {
+    x = {
+      a = 1;
+      b = "2";
+    };
+  };
+
+  tests = [
+    (root: false)
+    {
+      x = [
+        (set: true)
+        {
+          a = (a: a > 1);
+          b = (b: b == "3");
+        }
+      ];
+    }
+  ];
+
+  results = run "Examples" underTest tests;
+  */
+
+  passed = desc: {
+    result = "pass";
+    description = desc;
+  };
+
+  failed = desc: {
+    result = "failed";
+    description = desc;
+  };
+
+  prefixName = name: res: {
+    inherit (res) result;
+    description = "${name}: ${res.description}";
+  };
+
+  run = name: under: tests: if isList tests then
+    (concatLists (map (run name under) tests))
+  else if isAttrs tests then
+    (concatLists (map (
+    subName: run (name + "." + subName) (if hasAttr subName under then getAttr subName under else "<MISSING!>") (getAttr subName tests)
+    ) (attrNames tests)))
+  else if isFunction tests then
+    let
+      res = tests under;
+    in
+      if isBool res then
+        [
+          (prefixName name (if tests under then passed "passed" else failed "failed"))
+        ]
+      else
+        [ (prefixName name res) ]
+  else [
+    failed (name ": not a function, list or set")
+  ];
+in
+  { inherit run passed failed; }