We use flask-sqlalchemy (which wraps sqlalchemy) to talk to the database. We use flask-migrate (which wraps alembic) to manage database migrations.
How to make models (i.e., tables): https://flask-sqlalchemy.palletsprojects.com/en/2.x/models/
The database migration CLI: https://flask-migrate.readthedocs.io/en/latest/#command-reference
After creating a new model, run flask db migrate to create a new migration,
and flask db upgrade to apply the migration.
Commit migrations to git.
The production database is automatically upgraded in release-tasks.sh