diff --git a/jekyll-theme-guardian.gemspec b/jekyll-theme-guardian.gemspec
index 2fa76b8..223c558 100644
--- a/jekyll-theme-guardian.gemspec
+++ b/jekyll-theme-guardian.gemspec
@@ -10,7 +10,7 @@ Gem::Specification.new do |spec|
   spec.homepage      = "https://engineering.widen.com"
   spec.license       = "MIT"
 
-  spec.files         = `git ls-files -z`.split("\x0").select { |f| f.match(%r!^(assets|_layouts|_includes|_sass|LICENSE|README)!i) }
+  spec.files         = `git ls-files -z`.split("\x0").select { |f| f.match(%r!^(_config.yml|assets|_layouts|_includes|_sass|LICENSE|README)!i) }
 
   spec.add_runtime_dependency "jekyll", "~> 3.8.7"