But having a test framework always ready is useful. There is a "Test Driven Debugging": when you look around a bit inside the production error dumps, then try

But having a test framework always ready is useful. There is a "Test Driven Debugging": when you look around a bit inside the production error dumps, then try to reproduce it with a test, then debug the test in a much smaller scope with something heavy like Valgrind or a Record-Replay debugger (https://github.com/mozilla/rr https://github.com/mozilla/rr). If you write tests regularly during development then you can also isolate and test parts fast when something goes wrong in production.