Simon Willison Argues LLMs Make Open Source Devtools More Practical

In a blog post published on 3rd August 2026, Simon Willison argues that large language models (LLMs) have fundamentally changed the equation for open source software, making the original dream of examining and modifying code more feasible for everyday users. He notes that while the freedom to inspect and alter software has always been a core argument for open source, in practice most people—even expert programmers—relied on others to do that work due to the time commitment required. Willison explains that LLMs have reduced the friction of reading and modifying code: he now routinely prompts Claude to clone repositories from GitHub and explain how they work, and treats getting software to compile as a zero-time investment challenge, using tools like Codex or Claude Code to build projects while he steps away. Although he does not habitually modify the software he uses yet, he sees a clear path to that possibility that did not exist a year ago. The post is a comment on an article titled 'Devtools must be open source' hosted at exe.dev, and was shared on Hacker News. Willison also mentions that he offers a sponsored email digest for $10/month covering the month's most important LLM developments.