Know your unit economics
Track infra cost per active tenant or per thousand API calls. Without a unit, every optimization is vibes.
Right-size before you multi-region
Most early SaaS products need good single-region reliability and backups—not global complexity. Add regions when latency or compliance demands it.
Observability with budgets
Log everything forever is not a strategy. Sample, retain hot paths, and alert on user-facing SLOs.