We deploy and operate on Microsoft Azure: environments, CI/CD pipelines, release process and the monitoring that tells you whether any of it is working. We treat deployment as part of the engineering work rather than something handed over at the end.
Pipelines and environments
Separate environments for development, testing and production, with automated builds and deployments between them. A release should be an ordinary event, not one that needs a calendar invite.
Running it afterwards
Logging, alerting and the operational visibility needed to answer "is it healthy" without guessing — plus a path to roll back when a release does go wrong.