rollback-plan.txt
I'm about to deploy this change: <describe>

Before I do, write the rollback plan:
- The exact steps to get back to the current version.
- How long that takes, and whether anyone loses data doing it.
- Anything in this change that CANNOT be rolled back — schema changes,
  emails sent, third-party state — and how to make those reversible
  or safe to leave in place.
- The first three things I should check after deploying.

Code rolls back easily. Migrations, sent emails and charged cards do not. Know which of those you're about to do.