Incident Response, Typescript, Python, Postgres Sql, FastAPI, idempotency, multi-tenant architecture, row-level security, Disaster Recovery, leases, Next.js, database migrations, rollback, auditability, secrets management, production observability, ambiguous-write recovery, AI coding agents, end-to-end testing, retries, backpressure, dead-letter handling, least privilege security, tenant isolation, durable queues