What Simon Willison thinks about vibe coding

@simon-willison · 41 positions · 0 changes of mind

Co-creator of Django and creator of Datasette; writes daily at simonwillison.net.

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2 dated positions, 2026, in their own words. Our reading of what Simon Willison has said — not written or endorsed by them.

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1. 19 Mar 2026

   Our readingA team can stop reading the code it ships, but only by first working out how its agents are to prove that what they wrote actually works.

   Their wordsit turns out you can do this if you think really hard about okay, how do I have agents prove to me that the stuff they've written works?

   ↗Simon Willison: Engineering practices that make coding agents work - The Pragmatic Summityoutube.com 1st of 18 in this recording

3. 19 Mar 2026

   Our readingTrusting model-written code you have not read became defensible only with Opus 4.5, and only for classes of problem you have already watched a model handle.

   Their wordsI think Opus 4.5 was the first one that earned my trust. Like I'm very confident now that for classes of problems that I've seen it tackle before, it's not going to do anything stupid.

   ↗Simon Willison: Engineering practices that make coding agents work - The Pragmatic Summityoutube.com 2nd of 18 in this recording