'You can't find bugs by reading code.' A one-line post about code review split the experts

The one-line thesis, and the walk-back

Mark Jason Dominus (mjd), a mathematician and programmer, posted a deliberately sharp claim: the primary purpose of code review is to find code that will be hard to maintain, not to find bugs. His support was even sharper — "it is not in general possible to find bugs by examining the code" — plus a note on the asymmetric blame of bug-hunting: work yourself to exhaustion, find three bugs, and someone can still fault you for missing a fourth. (Mathstodon didn't render for this edition; the quoted lines are ones readers reproduced verbatim.)

Because that line lands harder than intended, the author came into the thread to bound it:

"The author is a mathematician, so when he says "it is not in general possible to find bugs by examining the code" he does not mean it is completely impossible to find bugs. He means only that it is not possible to find all bugs or even any particular bug." — Mark Jason Dominus, the post's author

The disagreement was the discovery

The narrowed claim didn't satisfy the sharpest critic:

"This just makes reviewers and authors lazier. The purpose of code review is multi-faceted. Hard to maintain? Yes. Might have bugs? Yes… This flippant note is mostly more self-justification for being a lazy code reviewer." — a WebAssembly co-founder and former V8 compiler lead

Someone who reviews for a living rejected the premise outright:

"in real code reviews bugs and errors are identified by reviewers all the time. Reviewers lend their past experience to the situation, identify some unnoticed interaction, think of an edge case that the author hadn't considered." — a high-karma commenter arguing from review experience

And then the comment that reframed the whole argument — the reason everyone was talking past each other:

"there isn't a "the" point of code review to discuss. It turns out that while we all may have thought we were doing it for the same reasons, we aren't. This is real. We don't have the same goals, we don't have the same methodology." — a veteran commenter with \~92k karma

That's the payload the headline was hiding. The fight wasn't really about bugs versus maintainability; it was two decades of engineers realizing that the ritual they all perform daily means a different thing to each of them — and that the disagreements about how to review are downstream of an unspoken disagreement about why.