To be a better programmer, write little proofs in your head

There's a quiet superpower that separates good programmers from great ones, and it has nothing to do with knowing more languages or frameworks. It's the ability to mentally sketch a proof, on the fly, that your code will actually do what you intend.

A software engineer recently laid out this deceptively simple idea, built around concepts like monotonicity, invariants, and induction. The core insight: if you can reason formally about your code while writing it, rather than after, you'll find it works correctly far more often on the first try.

The author argues that code quality can be measured by what they call "proof-affinity," meaning how easily you can convince yourself the code is correct. Hard-to-reason-about code is often a design problem in disguise.

And how do you get better at this kind of thinking? Write more mathematical proofs. Not just read them. Actually do the exercises. As the author puts it, it's a little like touch-typing: it only saves time once it's instinctual.