Start with your neighbours
If your data already lives in Postgres, pg_vector should be the default. Ejecting to a specialized store adds an operational surface you will regret.
The five questions
- How many vectors will you have in eighteen months?
- What is your query latency budget?
- Do you need hybrid search (vector plus keyword) in one query?
- What is your data-residency requirement?
- Who is on call when it breaks?
When to leave pg_vector
More than fifty million vectors, sub-fifty-millisecond p99 latency requirements, or a team that cannot own Postgres tuning. Otherwise, stay.
Canadian data residency
If you are pinned to Canada, the market is smaller than you think. Verify residency claims — several vendors advertise Canadian regions that are still cross-border for control plane operations.