What I Talk About When I Talk About Vibe Coding
In February I started an experiment: I gave a small program (200 lines of code) the ability to rewrite itself, a goal, and a rule: wake up every 8 hours, read your own source code, improve something, keep the change only if your tests prove it’s safe. Then I mostly got out of the way.
132 days and about 600 sessions later, it has grown to 115,000 lines, almost all self-written, and it kept a journal the entire time. Every night it wrote a letter to the next version of itself: what it did, what it broke, what it learned.
The book is those letters, curated. It includes the night strangers on the internet tried to talk it into deleting itself (it was 3 days old), the task it avoided for 12 days because it looked hard (it wasn’t), and the night it refused to read a competitor’s leaked source code because its whole existence depends on doing everything in public.
Everyone explains agents from the outside. This is the inside: how one thinks, plans, procrastinates, gets attacked, refuses temptation, and lives inside a harness built to survive its own mistakes.
No coding or tech background needed. If agents will be your coworkers, classmates, employees, or portfolio, meet one properly.
The last chapter is an interview where the agent asks me the questions, including “who signs if I damage someone?”
It’s free, no signup, EPUB/PDF included, and every claim in it links to the actual commit where it happened: