diff --git a/webmachine.gemspec b/webmachine.gemspec
index bb86578..0bf1dc5 100644
--- a/webmachine.gemspec
+++ b/webmachine.gemspec
@@ -33,6 +33,6 @@ Gem::Specification.new do |gem|
   gem.add_development_dependency('standard', ['~> 1.21'])
   ignores = File.read('.gitignore').split(/\r?\n/).reject { |f| f =~ /^(#.+|\s*)$/ }.map { |f| Dir[f] }.flatten
   gem.files = (Dir['**/*', '.gitignore'] - ignores).reject do |f|
-    !File.file?(f) || f.start_with?(*%w[. Gemfile RELEASING Rakefile memory_test spec webmachine.gemspec])
+    !File.file?(f) || f.start_with?(*%w[. Gemfile RELEASING Rakefile doc/ memory_test pkg/ spec/ vendor/ webmachine.gemspec])
   end
 end