Building Pi, and what makes self-modifying software so fascinating

About this episode

Mario Zechner and Armin Ronacher discuss the creation and implications of self-modifying AI coding agents.

Brought to You By: • Statsig — ⁠ The unified platform for flags, analytics, experiments, and more. • Sonar – The makers of SonarQube, the industry standard for automated code review • WorkOS – Everything you need to make your app enterprise ready. — Mario Zechner is the creator of Pi, a minimalist, self-modifying AI coding agent, that is the foundation upon which OpenClaw (created by Peter Steinberger) is built. Meanwhile, Armin Ronacher is the creator of Flask, and a longtime user of Pi. The pair are also friends. I sat down with Mario and Armin for the latest episode of the Pragmatic Engineer Podcast for an interesting conversation about AI and their reservations about it – even though both are heavily invested in building AI-powered tools. Mario explains why he built Pi, and gives his take on why it has become so popular. Armin walks us through how he uses AI tools, including building a game with Pi, and why he always puts human judgment firmly at the heart of his approach. We cover the risks of over-automation, the limits of agentic workflows, and why strong engineers with informed judgment still matter. We also get into the challenges of working with code written by…

People in this episode

Host: Gergely Orosz

Guests: Mario Zechner, Armin Ronacher

Topics covered

• self-modifying software
• AI coding agents
• automation risks
• human judgment in AI
• open source challenges

Keywords

• self-modifying software
• AI
• coding agents
• automation
• human judgment
• open source

Sponsors

Statsig, Sonar, WorkOS

Mentioned in this episode

Organizations: Flask, OpenClaw

Products: Pi

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