--- a/unf_ext.gemspec
+++ b/unf_ext.gemspec
@@ -13,30 +13,6 @@
   gem.homepage      = "https://github.com/knu/ruby-unf_ext"
   gem.licenses      = ["MIT"]
 
-  gem.files         = `git ls-files`.split($/)
-  gem.executables   = gem.files.grep(%r{^bin/}).map{ |f| File.basename(f) }
-  gem.test_files    = gem.files.grep(%r{^(test|spec|features)/}).grep(%r{/test_[^/]+\.rb$})
+  gem.files         = ["lib/unf_ext.rb", "lib/unf_ext/version.rb", "lib/unf_ext.so"]
   gem.require_paths = ["lib"]
-  gem.extensions    = ["ext/unf_ext/extconf.rb"]
-
-  gem.extra_rdoc_files = [
-    "LICENSE.txt",
-    "README.md"
-  ]
-
-  if RUBY_VERSION < "1.9"
-    gem.add_development_dependency("rake", [">= 0.9.2.2", "< 11"])
-    gem.add_development_dependency('i18n', '< 0.7.0')
-    # Cap dependency on activesupport with < 4.0 on behalf of
-    # shoulda-matchers to satisfy bundler.
-    gem.add_development_dependency("activesupport", ["< 4.0"])
-    gem.add_development_dependency("test-unit", ["= 3.1.5"])
-  else
-    gem.add_development_dependency("rake", [">= 0.9.2.2"])
-    gem.add_development_dependency("test-unit")
-  end
-  gem.add_development_dependency("rdoc", ["> 2.4.2"])
-  gem.add_development_dependency("bundler", [">= 1.2"])
-  gem.add_development_dependency("rake-compiler", [">= 0.7.9"])
-  gem.add_development_dependency("rake-compiler-dock", ["~> 0.7.0"])
 end