What is a “feature flag”?

Question

High Scalability mentions feature flags here:

5 things toxic to scalability, \"5. Lack of Feature Flags\"

What exactly are feature flags?

Answer 1

Feature Flag is a technique to turn some functionality of your application off, via configuration, without deploying new code.

Feature flags play a key part in CI scheme where features are constantly being deployed but not necessarily "released" into production.

More info here:

• http://code.flickr.com/blog/2009/12/02/flipping-out/

-- EDIT:

Feature Flags java implementation.