diff --git a/lib/sidekiq/web.rb b/lib/sidekiq/web.rb
index 06d68df5..0996f9f7 100644
--- a/lib/sidekiq/web.rb
+++ b/lib/sidekiq/web.rb
@@ -144,11 +144,11 @@ module Sidekiq
       m = middlewares
 
       ::Rack::Builder.new do
-        use Rack::Static, :urls => ["/stylesheets", "/images", "/javascripts"],
-                          :root => ASSETS,
-                          :cascade => true,
-                          :header_rules => [
-                            [:all, {'Cache-Control' => 'public, max-age=86400'}],
+        use Rack::Static, urls: ["/stylesheets", "/images", "/javascripts"],
+                          root: ASSETS,
+                          cascade: true,
+                          header_rules: [
+                            [:all, {"Cache-Control" => "public, max-age=86400"}]
                           ]
         m.each { |middleware, block| use(*middleware, &block) }
         use Sidekiq::Web::CsrfProtection unless $TESTING