diff --git a/Gemfile b/Gemfile
index 1a4b396ea..289d343da 100644
--- a/Gemfile
+++ b/Gemfile
@@ -1,11 +1,9 @@
 source "http://rubygems.org"
 
 platforms :rbx do
-  gem 'rubysl', '~> 2.0'
+  gem 'rubysl', '~> 2.2'
 end
 
 gemspec
 
-gem 'ffi-clang', :git => 'https://github.com/ioquatix/ffi-clang.git'
-
 # vim:ft=ruby
diff --git a/bin/cm b/bin/cm
index 69926540d..daa06c03e 100755
--- a/bin/cm
+++ b/bin/cm
@@ -13,6 +13,7 @@ version Docurium::Version
 desc 'Generate HTML documentation'
 long_desc 'Generate HTML docs from a Docurium config file'
 command :doc do |c|
+  c.flag :for, :desc => "The version to generate", :multiple => true
   c.action do |global_options,options,args|
     file = args.first
     Docurium::CLI.doc(file, options)
@@ -34,8 +35,10 @@ pre { |global,command,options,args| true }
 post { |global,command,options,args| true }
 
 on_error do |exception|
-  puts exception
-  puts exception.backtrace
+  if !exception.is_a?(SystemExit)
+    puts exception
+    puts exception.backtrace
+  end
 end
 
 exit run(ARGV)
diff --git a/docurium.gemspec b/docurium.gemspec
index d64e5f316..1097a92c2 100644
--- a/docurium.gemspec
+++ b/docurium.gemspec
@@ -14,14 +14,15 @@ Gem::Specification.new do |s|
   s.license = 'MIT'
 
   s.add_dependency "version_sorter", "~>2.0"
-  s.add_dependency "mustache", "~> 0.99"
+  s.add_dependency "mustache", "~> 1.1"
   s.add_dependency "rocco", "~>0.8"
   s.add_dependency "gli", "~>2.5"
   s.add_dependency "rugged", "~>0.21"
   s.add_dependency "redcarpet", "~>3.0"
-  s.add_dependency "ffi-clang", "~> 0.2"
+  s.add_dependency "ffi-clang", "~> 0.5"
   s.add_development_dependency "bundler",   "~>1.0"
-  s.add_development_dependency "rake", "~> 10.1"
+  s.add_development_dependency "rake", "~> 12"
+  s.add_development_dependency "minitest", "~> 5.11"
 
   s.files         = `git ls-files`.split("\n")
   s.test_files    = `git ls-files -- {test,spec,features}/*`.split("\n")
diff --git a/lib/docurium.rb b/lib/docurium.rb
index 16105896b..f8ad66160 100644
--- a/lib/docurium.rb
+++ b/lib/docurium.rb
@@ -23,7 +23,7 @@ def initialize(config_file, repo = nil)
     raise "You need to specify a config file" if !config_file
     raise "You need to specify a valid config file" if !valid_config(config_file)
     @sigs = {}
-    @repo = repo || Rugged::Repository.discover('.')
+    @repo = repo || Rugged::Repository.discover(config_file)
   end
 
   def init_data(version = 'HEAD')
@@ -119,12 +119,22 @@ def generate_doc_for(version)
     data
   end
 
-  def generate_docs
+  def generate_docs(options)
     output_index = Rugged::Index.new
     write_site(output_index)
     @tf = File.expand_path(File.join(File.dirname(__FILE__), 'docurium', 'layout.mustache'))
     versions = get_versions
     versions << 'HEAD'
+    # If the user specified versions, validate them and overwrite
+    if !(vers = options[:for]).empty?
+      vers.each do |v|
+        next if versions.include?(v)
+        puts "Unknown version #{v}"
+        exit(false)
+      end
+      versions = vers
+    end
+
     nversions = versions.size
     output = Queue.new
     pipes = {}
diff --git a/lib/docurium/cli.rb b/lib/docurium/cli.rb
index 38233ba11..c3d063956 100644
--- a/lib/docurium/cli.rb
+++ b/lib/docurium/cli.rb
@@ -3,7 +3,7 @@ class CLI
 
     def self.doc(idir, options)
       doc = Docurium.new(idir)
-      doc.generate_docs
+      doc.generate_docs(options)
     end
 
     def self.gen(file)
diff --git a/lib/docurium/docparser.rb b/lib/docurium/docparser.rb
index 3aee80a9b..fd50fec02 100644
--- a/lib/docurium/docparser.rb
+++ b/lib/docurium/docparser.rb
@@ -18,7 +18,7 @@ def parse_file(orig_filename, files)
       unsaved = files.map do |name, contents|
         full_path = File.join(tmpdir, name)
         dirname = File.dirname(full_path)
-        FileUtils.mkdir_p(dirname) unless Dir.exists? dirname
+        FileUtils.mkdir_p(dirname) unless Dir.exist? dirname
         File.new(full_path, File::CREAT).close()
 
         UnsavedFile.new(full_path, contents)
diff --git a/test/repo_test.rb b/test/docurium_test.rb
similarity index 99%
rename from test/repo_test.rb
rename to test/docurium_test.rb
index ae515fdfa..1a8e57c8c 100644
--- a/test/repo_test.rb
+++ b/test/docurium_test.rb
@@ -2,7 +2,7 @@
 require 'docurium'
 require 'rugged'
 
-class DocuriumTest < MiniTest::Unit::TestCase
+class DocuriumTest < Minitest::Test
 
   def setup
     @dir = Dir.mktmpdir()
diff --git a/test/gen_test.rb b/test/gen_test.rb
index cf7e62a22..260d64a52 100644
--- a/test/gen_test.rb
+++ b/test/gen_test.rb
@@ -3,7 +3,7 @@
 require 'docurium/cli'
 require 'tempfile'
 
-class GenTest < MiniTest::Unit::TestCase
+class GenTest < Minitest::Test
 
   # make sure we can read what we give the user
   def test_read_generated_file
@@ -12,7 +12,7 @@ def test_read_generated_file
       Docurium::CLI.gen(file.path)
     end
 
-      Docurium.new file.path
+    assert_raises(Rugged::RepositoryError) { Docurium.new file.path }
   end
 
 end
diff --git a/test/parser_test.rb b/test/parser_test.rb
index 16db74616..560cfdd54 100644
--- a/test/parser_test.rb
+++ b/test/parser_test.rb
@@ -2,7 +2,7 @@
 require 'docurium'
 require 'pp'
 
-class TestParser < Minitest::Unit::TestCase
+class ParserTest < Minitest::Test
 
   def setup
     @parser = Docurium::DocParser.new