Simon Willison’s Weblog

Last year the most useful exercise for getting a feel for how good LLMs were at writing code was vibe coding (before that name had even been coined) - seeing if you could create a useful small application through prompting alone.

Today I think there's a new, more ambitious and significantly more intimidating exercise: spend a day working on real production code through prompting alone, making no manual edits yourself.

This doesn't mean you can't control exactly what goes into each file - you can even tell the model "update line 15 to use this instead" if you have to - but it's a great way to get more of a feel for how well the latest coding agents can wield their edit tools.