> integration tests Yes. I remember working in a 700,000+ line PHP code base that around 30% unit test coverage and an unknown percentage of e2e test coverage.

> integration tests Yes. I remember working in a 700,000+ line PHP code base that around 30% unit test coverage and an unknown percentage of e2e test coverage. I kept my changes very localised because it was a minefield. Also, the unit tests didn't do teardown so adding a new unit test required you to slot it in with assertions accounting for the state of all tests run so far.