> This is validated at compile time against a database, which is good, but of course there is no guarantee that the production database will have the same types

> This is validated at compile time against a database, which is good, but of course there is no guarantee that the production database will have the same types. Easiest mistake to make is to design a query against your local Postgres v15 and hit a runtime error in production running Postgres v12, e.g. a function like gen_ramdom_uuid() doesn't exist. Another is to assume a migration in production was actually executed. One could have the backend fetch DB schema/version info at startup, compare it to its own view of what the schema should look like, and fail if the two disagree. That way, a new deployment would fail before being activated, instead of being deployed successfully and queries failing down the line.