This is the single most impactful blog post I've read in the last 2-3 years. It's so obvious in retrospect, but it really drove the point home for me that functional correctness is only the beginning. I personally had been over-indexing on functional correctness, which is understandable since a reliable but incorrect system isn't valuable.

But, in practice, I've spent just as much time on issues introduced by perf / scalability limitations. And the post thesis is correct: we don't have great tools for reasoning about this. This has been pretty much all I've been thinking about recently.