Episode 16
More productive but a lot less fun — with Charlie Marsh
Charlie Marsh built Ruff, uv, and Ty — the tools that mass-fixed Python's worst pain points. Now he's grappling with what happens when agents start writing most of the code. In this episode, Charlie gets real about his team trusting his PRs less, the gnarly middle of coding with agents, and whether Python is even the right language for an agentic future. It's honest, a wee existential, and deeply relatable if you ship code for a living.
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EPISODE NOTES
Charlie Marsh is the founder and CEO of Astral — the company behind Ruff, uv, and Ty. He sits down with Michael and Wes to talk about what it's actually like building with coding agents every day, why his team's code review dynamics completely changed, and big open questions about code quality, open source community, and Python's future nobody has answers to yet.
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What's Inside:
- How Ruff convinced mass adoption when switching tools is painful
- Why "just uv run it" became the killer feature
- Hiring outside Python's ecosystem to build tools for it
- His team said "we trust your PRs less now"
- Engineers screen-sharing their actual agent workflows at Astral
- The "Lisp Curse" reborn: cheap code breaking open source
- Is Python the wrong language for an agentic world?
HOSTS & GUESTS
Principal Software Engineer, Posit
Michael Chow
Principal Architect, Posit
Wes McKinney
Founder & CEO, Astral
Charlie Marsh