10 - Richard Feldman on Roc, AI, Teaching, and Avoiding Fancy Functional Programming

Richard Feldman is a software engineer with more than 20 years of experience, a frequent conference speaker, teacher and author of Elm in Action. He's the author of the Roc programming language and is currently working on Zed, the AI-enabled code editor.

Zed: https://zed.dev/ Roc: https://www.roc-lang.org/

---

0:00 Intro 1:38 Why Rust's borrow checker didn't help Roc's compiler 6:02 Zig vs Rust for Roc: trade-offs in practice 8:29 Why Richard built Roc 13:11 Roc vs Go for web servers 18:02 Roc's error handling: anonymous sum types 19:44 How Roc measures success 23:22 Roc adoption: the startup pathway 29:54 Platforms and applications: Roc's core design 40:33 Security by design: sandboxing dependencies 55:00 Avoiding monads: Richard's FP philosophy 1:02:36 Empathy as a design principle 1:05:04 Teaching FP: don't start with types 1:09:32 Writing Elm in Action: lessons and regrets 1:17:35 Career decisions: startups and red flags 1:30:08 Fundamentals: API design and OOP skepticism 1:40:14 Roc in the age of AI 1:47:24 Vibe coding and software quality 1:54:51 AI agents for bug reproduction in Roc 2:08:09 What drives Richard: people and products