Multi-tenant from day one: the decision that saved me

This piece is published as an outline: the statement and the structure are settled, the full text is coming.

The cost of postponing

Adding isolation to a schema that assumed a single customer is not a migration: it is a rewrite with customers on top of it.

Isolation in the database, not the code

Row level security: the query you forget to filter cannot return another tenant’s rows, because the engine will not let it.

When one tenant grows ten times faster

Partitioning, per-tenant indexes and the noisy neighbour.

What eight years taught

What I would do the same way again, and what I would not.