X_DB_SERIALIZATION_FAILURE
Means
the transaction lost a serialization race
Typical cause
SQLSTATE 40001 or 40P01 — a serializable transaction whose read set another commit invalidated, or a deadlock the server broke. Retryable by definition, which is why it is its own code and not an outage
Fix
withTransaction(fn, { retry: 3 }) — fn re-runs from the top, so it must be idempotent