The release model
Apex models a release as a sequence: preview, canary, full production. Each stage uses the same deployment artifact, which keeps rollback deterministic.
1. Define the canary
apex traffic set --environment production \ --version dep_01J9QW2P9H --percent 10
Ten percent is a starting point, not a universal default. Choose the initial percentage from your traffic volume and the potential blast radius of the change.
2. Watch the right metrics
- Error rate by version.
- p95 latency by route and region.
- Dependency error rate and upstream latency.
- Business-level conversion or success signals when available.
3. Promote or roll back
apex traffic set --environment production --version dep_01J9QW2P9H --percent 100 # rollback apex traffic set --environment production --version dep_01J8M5H7K --percent 100
A rollback changes the active version. It does not mutate the artifact or require a fresh build.
Prepare for regional state
The next step is to decide how caches and persistent data behave when compute is distributed.