# I'm starting a interview series of people working in Lean / formal methods / math formalization

> Source: <https://www.lesswrong.com/posts/CqmQ7rh23w8ZaaKqz/i-m-starting-a-interview-series-of-people-working-in-lean>
> Published: 2026-08-15 14:00:16+00:00

I think the topics of discussion would be of interest to a lot of people here, so I thought I'd share the first episode:

Tanner Duve is a Member of Technical Staff at Logical Intelligence working on formal verification and compilers in Lean, an open-source contributor to Mathlib and CSLib, and a former D1 football player.

I sat down with him for a conversation about his work and his thoughts on the future of AI-assisted math formalization.

Chapters:

[00:00](https://www.youtube.com/watch?v=GqsBVW3d_vc) Intro[05:12](https://www.youtube.com/watch?v=GqsBVW3d_vc&t=312s) Social aspect of formal verification[07:34](https://www.youtube.com/watch?v=GqsBVW3d_vc&t=454s) Contributing to mathlib and CSLib[15:57](https://www.youtube.com/watch?v=GqsBVW3d_vc&t=957s) AlgoLean [23:17](https://www.youtube.com/watch?v=GqsBVW3d_vc&t=1397s) What is a Free Monad? [34:27](https://www.youtube.com/watch?v=GqsBVW3d_vc&t=2067s) Turing (in)completeness in Lean [43:13](https://www.youtube.com/watch?v=GqsBVW3d_vc&t=2593s) AI in math formalization [46:22](https://www.youtube.com/watch?v=GqsBVW3d_vc&t=2782s) Where did you learn type theory? [49:49](https://www.youtube.com/watch?v=GqsBVW3d_vc&t=2989s) Lean vs Rocq vs Haskell [51:50](https://www.youtube.com/watch?v=GqsBVW3d_vc&t=3110s) Favorite concept in type theory [55:16](https://www.youtube.com/watch?v=GqsBVW3d_vc&t=3316s) Rust's type theory [56:57](https://www.youtube.com/watch?v=GqsBVW3d_vc&t=3417s) Pedagogy of PL theory [59:52](https://www.youtube.com/watch?v=GqsBVW3d_vc&t=3592s) When did you decide to work in PL theory? [1:02:06](https://www.youtube.com/watch?v=GqsBVW3d_vc&t=3726s) Formal verification pre-AI vs. now [1:05:19](https://www.youtube.com/watch?v=GqsBVW3d_vc&t=3919s) Playing D1 football in college [1:08:16](https://www.youtube.com/watch?v=GqsBVW3d_vc&t=4096s) Veganism [1:12:17](https://www.youtube.com/watch?v=GqsBVW3d_vc&t=4337s) Advice