I have always used asserts to enforce invariants (sometimes not just actual "assert" but things like `Preconditions` in Java which are always enabled). Those wi

I have always used asserts to enforce invariants (sometimes not just actual "assert" but things like `Preconditions` in Java which are always enabled). Those will actually break during testing if they ever change. I understand you cannot assert all invariants, but as far as I can see, that's your main tool against this problem.