Using feature-flags. It is a boolean attribute that gets controlled via an interface. The codebase (Front end as well as backend) build features based on the value of a feature-flag.

When a build is open to public, a load balancer will strategically deviate the traffic between two features and the analytics code will pickup the metrics which will be later used for analysis.

Post build process, based on the review of usage or conversion rate, the feature code cleanup will be done.