Dos and Donts of Feature Flagging

This page is really just a collection of small bits of advice we've gathered while putting together this project and using feature flags within our applications...

DO give your feature flags sensible names - this will make using them in your application much nicer.

DO use feature flags for positively enabling new features - i.e. show-new-search, show-article-metrics - this means that the flag has to have a 'true' enabled state in order for the new feature to be displayed/used.

DON'T use feature flags for suppressing new features - i.e. hide-new-search, hide-article-metrics - the reason for this is that your feature flags should have a safe default. If Bandiera fails or a network error occurs between your app and Bandiera and you are using feature flags in this way, your new features will be switched on by default as they will no longer be hidden.