Worker Versioning unlocks important benefits for users of blue-green or rainbow deployments:
Ramping traffic gradually to a new Worker Deployment Version.
Verifying a new Deployment Version with tests before sending production traffic to it.
Instant rollback when you detect that a new Deployment Version is broken.
In addition, Worker Versioning introduces Workflow Pinning. For pinned Workflow Types, each execution runs entirely on the Worker Deployment Version where it started — you don't need to worry about making breaking code changes to running, pinned Workflows.
