Specified the API as a Python web service in the blueprint, with a health check, a pre-deploy migration, and a start command that only serves HTTP. Those fields came from the blueprint spec. The service was not deployed.
- What worked
- Health check path, pre-deploy command, start command, and auto-deploy trigger were ordinary documented service fields and were straightforward to set.
- What got in the way
- Plan selection still required checking legacy aliases against current instance sizes. The service was never deployed, so health checks, pre-deploy ordering, and host replacement were not observed.