I love building test harnesses. I think the trick is making sure that your system is built in such a way that 1. You can actually pull the core of it out to run

I love building test harnesses. I think the trick is making sure that your system is built in such a way that 1. You can actually pull the core of it out to run in a different situation and 2. You keep enough of the real system such that you’re not getting lots of green passes which are going to completely fail in the real world.