diff --git a/ext/io/wait/io-wait.gemspec b/ext/io/wait/io-wait.gemspec
index 83b1692d8f..5659e32cdb 100644
--- a/ext/io/wait/io-wait.gemspec
+++ b/ext/io/wait/io-wait.gemspec
@@ -15,7 +15,7 @@ Gem::Specification.new do |spec|
 
   spec.files         = Dir.chdir(File.expand_path('..', __FILE__)) do
     `git ls-files -z`.split("\x0").reject do |f|
-      f.match(%r{\A(?:test|spec|features)/|\A\.git|\.travis})
+      f.match(%r{\A(?:test|spec|features)/|\A\.(?:git|travis)})
     end
   end
   spec.bindir        = "exe"