Make an index earn its place in a write-heavy table
Evaluate a PostgreSQL status index against both its read benefit and update work. Use HOT statistics as evidence about the mechanism, not as a speed score.
Rust database boundaries
Check index write costs, tenant isolation, and database permissions. Each guide gives a concrete reproduction, the resulting decision, and the limits of the evidence.
Put two tenants in your authorization tests
A one-tenant fixture cannot show cross-tenant access bugs. Exercise reads, writes, and reused database connections with two independent customer scopes.
Run reports with a database account that cannot write
Give a reporting service narrow database permissions and test denied writes using its real account. Read-only access still needs data and resource limits.