diff --git a/lib/flipper/adapters/dalli.rb b/lib/flipper/adapters/dalli.rb
index <HASH>..<HASH> 100644
--- a/lib/flipper/adapters/dalli.rb
+++ b/lib/flipper/adapters/dalli.rb
@@ -92,7 +92,7 @@ module Flipper
       private
 
       def key_for(feature)
-        feature
+        feature.to_s
       end
     end
   end
Get explicit about key used for dalli

Deep in dalli, it was doing feature.to_s so now we just do this in flipper in case dalli ever stops doing that.