How to incrementally introduce functionality to micro-service-based deployments:
- add new thing to data source (if needed)
- use new thing to backend
- use new thing in client
- remove old thing in client
- remove old thing from backend (as all client nodes have upgraded)
- remove old thing from database (if data source changed, as all backend nodes have upgraded)
How to incrementally introduce functionality to environment-based deployments:
- add new thing to QA data source (if needed)
- use new thing to QA backend
- use new thing in QA client
- add new thing to Prod data source (if needed)
- use new thing to Prod backend
- use new thing in Prod client
- remove old thing in QA client
- remove old thing from QA backend
- remove old thing from QA data source (if data source changed)
- remove old thing in Prod client
- remove old thing from Prod backend
- remove old thing from Prod data source (if data source changed)