What are "Feature Toggles" and "Feature Branches" and what's the difference between them?
What are the pros and cons? Why is one better than the other?
I found some articles on Google regarding this, and I tend to be in the "Feature Toggles" camp, but I'm not convinced that "Feature Toggles" is the better choice in all the cases.
Feature toggles are methodology used in a Continuous Integration/Continuous Delivery (CI/CD) chain (Agile/Kanban project methodology). Basically, you send new features to production in a disabled state, then in an admin console turn the feature on (or off if you discover it's broken).
Feature branches can be part of a release methodology and integrated into a continuous integration chain. You can develop in a feature branch, deploy the branch to DEV/QA, get certification, merge the feature branch to trunk, then push the trunk to SIT/UAT/PROD environments.
There are pros and cons associated with this approach. Feature toggling requires very strict discipline as broken/dark code is making it to production. This is great for startups and shops where management knows how to pull this off and has system automation tools in place (Chef/Puppet/cfengine, etc.) Google, Facebook, LinkedIn, WordPress all deploy to production environments using feature toggling and system automation.
There are some prerequisite "techs" to do feature toggling properly: Continuous Delivery/Deployment, Continuous Integration, Automated Unit Testing, Automated Integration Testing, Automated Stress/Performance Testing, System Automation. If you don't have these in place, consider a simpler release strategy (e.g. feature branching.)