This is the kind of mathematics I was put on this earth to do. The equation explorer is also just a genuinely useful tool for looking up equations; did so earlier this year as part of preparations for a lecture I gave.

“Correct” doesn’t mean “correct” when correctly using “correct”

via: https://buttondown.com/hillelwayne/archive/three-ways-formally-verified-code-can-go-wrong-in/

This is how we do math in the 21st century.

Users often struggle with cloud file-sharing applications. Problems appear to arise not only from interface flaws, but also from misunderstanding the underlying semantics of operations like linking, attaching, downloading, and editing. We argue that these difficulties echo long-standing challenges in understanding concepts in programming languages like aliasing, copying, and mutation.

via: https://blog.brownplt.org/2025/08/25/cloud-sharing.html

see also: https://www.hillelwayne.com/talks/informal-specification/

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