I keep hoping Postgres will one day have the ability to mark a timestamp column as an expiry column. It would be useful for all kinds of things beyond caching, including session tokens, feature flags, background jobs, rate limiting, delayed deletion (as a variant of soft deletion), etc.

It seems like the autovacuum could take care of these expired rows during its periodic vacuum. The query planner could automatically add a condition that excludes any expired rows, preventing expired rows from being visible before autovacuum cleans them up.