SER-03 · SER-03.04 · SaaS Systems: Architecture, Cost and Simplicity
What 2.6 million Ordovia requests taught me about SaaS architecture
The main lesson was not about choosing a cheaper backend. It was about being able to explain why the system talks to the backend at all.
Ordovia reached roughly 2.6 million monthly Supabase requests before it had a user scale that made the number feel natural. The useful question became: which product behaviors were producing that traffic?
A backend bill can be the price of not being able to explain your own system's behavior.
The lessons
Total request count is not enough; measure per user, session, route and feature.
Feature-local fetching decisions accumulate into system-wide cost.
Cloud-first does not mean cloud-every-second.
Polling should be justified rather than default.
Cache is a system policy and cost control, not just a speed trick.
Mutation invalidation should target affected domains.
Fix application behavior before changing infrastructure vendors.
Request per active user per day is a useful health signal.