diff --git a/logstash-input-gelf.gemspec b/logstash-input-gelf.gemspec
index 5329519..9ae7929 100644
--- a/logstash-input-gelf.gemspec
+++ b/logstash-input-gelf.gemspec
@@ -11,7 +11,7 @@ Gem::Specification.new do |s|
   s.require_paths = ["lib"]
 
   # Files
-  s.files = `git ls-files`.split($\)+::Dir.glob('vendor/*')
+  s.files = Dir['lib/**/*','spec/**/*','vendor/**/*','*.gemspec','*.md','CONTRIBUTORS','Gemfile','LICENSE','NOTICE.TXT']
 
   # Tests
   s.test_files = s.files.grep(%r{^(test|spec|features)/})