Add cache control headers for assets

config/environments/production.rb

@@ -23,6 +23,12 @@ Rails.application.configure do
   # Disable serving static files from `public/`, relying on NGINX/Apache to do so instead.
   # config.public_file_server.enabled = false
 
+  # Set cache headers for static files
+  config.public_file_server.headers = {
+    'Cache-Control' => 'public, max-age=31536000',
+    'Expires' => 1.year.from_now.to_formatted_s(:rfc822)
+  }
+
   # Compress CSS using a preprocessor.
   # config.assets.css_compressor = :sass