Browser UseFrom the builder
Everything I Got Wrong in the Last 4,000 Commits
Browser Use's first engineer, who joined in April 2025, made more than 4,000 commits in a year building cloud infrastructure for millions of agent runs, and reviews the mistakes made along the way in chronological order. They include a free-credits endpoint that could be claimed repeatedly, round() making LLM calls under half a credit free, and a March 2026 load test against production machines that caused 45 minutes of downtime. The author groups the lessons into assuming instead of checking, skipping full-path tests, favoring clever fixes over simple ones, leaving fixes unfinished and building features nobody asked for.
The gap between "works in a demo" and "works at scale" is about 4,000 commits. This is what most of them looked like.
Saved . A shortened excerpt from the official blog; the original publisher retains authorship.