diff --git a/omniauth.gemspec b/omniauth.gemspec
index 30d4f57..456a2a5 100644
--- a/omniauth.gemspec
+++ b/omniauth.gemspec
@@ -11,9 +11,7 @@ Gem::Specification.new do |spec|
   spec.cert_chain    = %w(certs/sferik.pem)
   spec.description   = %q{A generalized Rack framework for multiple-provider authentication.}
   spec.email         = ['michael@intridea.com', 'sferik@gmail.com']
-  spec.files         = %w(.yardopts LICENSE.md README.md Rakefile omniauth.gemspec)
-  spec.files        += Dir.glob('lib/**/*.rb')
-  spec.files        += Dir.glob('spec/**/*')
+  spec.files         = `git ls-files`.split($/)
   spec.homepage      = 'http://github.com/intridea/omniauth'
   spec.licenses      = ['MIT']
   spec.name          = 'omniauth'
@@ -21,6 +19,6 @@ Gem::Specification.new do |spec|
   spec.required_rubygems_version = '>= 1.3.5'
   spec.signing_key   = File.expand_path('~/.gem/private_key.pem') if $PROGRAM_NAME =~ /gem\z/
   spec.summary       = spec.description
-  spec.test_files    = Dir.glob('spec/**/*')
+  spec.test_files    = spec.files.grep(%r{^spec/})
   spec.version       = OmniAuth::VERSION
 end