The Peterman Pod

Charlie Marsh is the founder of Astral, the Python devtool startup that was acquired by OpenAI. I inteviewed him about how software engineering is changing and learnings from starting his own company as an engineer.

• My ergonomic keyboard project I mentioned, you can follow along here: https://read.compose.llc/
• The Kickstarter page for it: https://www.kickstarter.com/projects/ryanlpeterman/compose-simple-ergonomics-beautifully-done

Podcast links:

• YouTube: https://youtu.be/Iw65FD4MGgs
• Apple: https://podcasts.apple.com/us/podcast/the-peterman-pod/id1777363835
• Transcript: https://www.developing.dev/p/openai-eng-and-dev-tools-founder

Thank you to this episode's sponsor for supporting my work:

• WorkOS: makes your app Enterprise Ready with easy to use APIs to add SSO, SCIM, RBAC, and more in just a few lines of code, check them out at https://workos.com/

Timestamps:

(00:00) Intro
(00:40) Origin story
(06:04) The front page of Hacker News
(14:35) Why he chose Rust
(20:10) Full codebase migration from Zig to Rust
(28:40) LLM generated code and open source
(35:34) Performance optimizations
(44:54) Optimization with AI and combating slop
(01:02:08) Learnings as an eng starting a company
(01:17:55) Top technical talk recommendation
(01:18:56) Advice for his younger self
(01:22:00) Outro

Where to find Charlie:

• LinkedIn: https://www.linkedin.com/in/marshcharles/
• GitHub: https://github.com/charliermarsh
• X/Twitter: https://x.com/charliermarsh

Where to find Ryan:

• Newsletter: https://www.developing.dev/
• X/Twitter: https://x.com/ryanlpeterman
• LinkedIn: https://www.linkedin.com/in/ryanlpeterman/
• Threads: https://www.threads.com/@ryanlpeterman
• Instagram: https://www.instagram.com/ryanlpeterman
• TikTok: https://www.tiktok.com/@ryanlpeterman

Referenced in this episode:

• Python tooling could be much, much faster: https://notes.crmarsh.com/python-tooling-could-be-much-much-faster
• The coolest PR he's ever seen: https://github.com/astral-sh/uv/pull/789
• Andrew Kelley’s data-oriented design talk: https://www.youtube.com/watch?v=IroPQ150F6c
• Ruff: https://github.com/astral-sh/ruff
• uv: https://github.com/astral-sh/uv
• ty: https://github.com/astral-sh/ty
• Salsa: https://github.com/salsa-rs/salsa

Vlad Feinberg is Google DeepMind’s pre-training area lead and I asked him all about how to land a job at a frontier lab like Google DeepMind, Anthropic or OpenAI.

• My ergonomic keyboard project I mentioned, you can follow along here: https://read.compose.llc/
• The Kickstarter page for it: https://www.kickstarter.com/projects/ryanlpeterman/compose-simple-ergonomics-beautifully-done

Podcast links:

• YouTube: https://youtu.be/cDyi91onoJ8
• Apple: https://podcasts.apple.com/us/podcast/the-peterman-pod/id1777363835
• Transcript: https://www.developing.dev/p/google-deepmind-pre-training-lead

Thank you to this episode's sponsor for supporting my work:

• WorkOS: makes your app Enterprise Ready with easy to use APIs to add SSO, SCIM, RBAC, and more in just a few lines of code, check them out at https://workos.com/

Timestamps:

(00:00) Intro
(00:33) Skills frontier labs need
(08:45) The difference between AI research and engineering
(21:41) Domains that matter for the frontier
(30:50) Marketing yourself to frontier labs
(35:13) Concrete steps engineers can take
(38:29) Overview of pre-training areas
(47:23) Jeff Dean spot bonus story
(50:14) Favorite Gemini war story
(58:59) Advice for his younger self
(01:03:07) Outro

Where to find Vlad:

• Personal Website: https://vladfeinberg.com/
• Twitter/X: https://x.com/FeinbergVlad
• LinkedIn: https://www.linkedin.com/in/vladimirfeinberg/

Where to find Ryan:

• Newsletter: https://www.developing.dev/
• X/Twitter: https://x.com/ryanlpeterman
• LinkedIn: https://www.linkedin.com/in/ryanlpeterman/
• Threads: https://www.threads.com/@ryanlpeterman
• Instagram: https://www.instagram.com/ryanlpeterman
• TikTok: https://www.tiktok.com/@ryanlpeterman

Referenced in this episode:

• How to Land a Job at a Frontier Lab: https://vladfeinberg.com/2026/05/10/how-to-land-a-job-at-a-frontier-lab.html
• ThunderKittens: https://github.com/HazyResearch/ThunderKittens
• Deedy's doomer Tweet: https://x.com/FeinbergVlad/status/2056383124829872466?s=20
• Jacob Steinhardt's "Research as a Stochastic Decision Process": https://cs.stanford.edu/~jsteinhardt/ResearchasaStochasticDecisionProcess.html
• The Scaling Book: https://jax-ml.github.io/scaling-book/
• Dwarkesh and Reiner's video: https://www.youtube.com/watch?v=xmkSf5IS-zw

Simon Peyton Jones is the co-creator of Haskell (pure functional programming language) and I interviewed him about functional programming, why it matters, and his thoughts on other programming languages.

• My ergonomic keyboard project I mentioned, you can follow along here: https://read.compose.llc/

Podcast links:

• YouTube: https://youtu.be/xcB_LF3cdqw
• Apple: https://podcasts.apple.com/us/podcast/the-peterman-pod/id1777363835
• Transcript: https://www.developing.dev/p/co-creator-of-haskell-functional

Thank you to this episode's sponsor for supporting my work:

• WorkOS: makes your app Enterprise Ready with easy to use APIs to add SSO, SCIM, RBAC, and more in just a few lines of code, check them out at https://workos.com/

Timestamps:

(00:00) Intro
(00:39) What functional programming is
(09:18) Downsides of functional programming
(10:53) Specialized hardware for functional programming
(21:47) Haskell is useless
(25:59) Rust vs C
(28:26) Haskell vs OCaml
(35:26) Side effects in Haskell
(44:26) Type systems
(57:30) How the Haskell compiler works
(01:04:35) Why Haskell is talked about more than used
(01:09:07) Avoiding success at all costs
(01:11:12) LLMs and programming languages
(01:13:57) New programming language design
(01:15:59) Should students continue to learn programming
(01:22:33) Why Excel is his 2nd favorite programming language
(01:25:04) Advice for his younger self

Where to find Simon:

• LinkedIn: https://www.linkedin.com/in/simonpj/
• Wikipedia: https://en.wikipedia.org/wiki/Simon_Peyton_Jones
• Personal Website: https://simon.peytonjones.org/

Where to find Ryan:

• Newsletter: https://www.developing.dev/
• X/Twitter: https://x.com/ryanlpeterman
• LinkedIn: https://www.linkedin.com/in/ryanlpeterman/
• Threads: https://www.threads.com/@ryanlpeterman
• Instagram: https://www.instagram.com/ryanlpeterman
• TikTok: https://www.tiktok.com/@ryanlpeterman

Referenced in this episode:

• Haskell is useless: https://www.youtube.com/watch?v=iSmkqocn0oQ
• John Backus Turing Award lecture: https://worrydream.com/refs/Backus_1978_-_Can_Programming_Be_Liberated_from_the_von_Neumann_Style.pdf
• Why functional programming matters: https://www.cs.kent.ac.uk/people/staff/dat/miranda/whyfp90.pdf
• Excel is his 2nd favorite programming language: https://www.youtube.com/watch?v=_M4P5M85KO8

Avi Wigderson is the only person in history to have won both a Turing Award (computer science) and Abel Prize (math). I interviewed him all about his field.

• My ergonomic keyboard project I mentioned, you can follow along here: https://read.compose.llc/

Podcast links:

• YouTube: https://youtu.be/5GUcvSAJcJw
• Apple: https://podcasts.apple.com/us/podcast/the-peterman-pod/id1777363835
• Transcript: https://www.developing.dev/p/turing-award-winner-p-vs-np-zero

Thank you to this episode's sponsor for supporting my work:

• WorkOS: makes your app Enterprise Ready with easy to use APIs to add SSO, SCIM, RBAC, and more in just a few lines of code, check them out at https://workos.com/

Timestamps:

(00:00) Intro
(01:08) P vs NP
(14:51) What if you relaxed correctness
(25:38) Why NP complete problems are equivalent
(30:33) Space vs time complexity
(43:06) Why people use SAT solvers
(45:53) Randomness is a resource
(55:48) Randomness depends on computational power
(01:21:20) Zero knowledge proofs and their significance
(01:38:30) Quantum computation and why it matters
(01:56:24) Math vs computer science
(02:08:16) Major breakthroughs and his experience
(02:12:31) Advice for his younger self
(02:14:48) Outro

Where to find Avi:

• Wikipedia: https://en.wikipedia.org/wiki/Avi_Wigderson
• Personal Website: https://www.math.ias.edu/avi/home

Where to find Ryan:

• Newsletter: https://www.developing.dev/
• X/Twitter: https://x.com/ryanlpeterman
• LinkedIn: https://www.linkedin.com/in/ryanlpeterman/
• Threads: https://www.threads.com/@ryanlpeterman
• Instagram: https://www.instagram.com/ryanlpeterman
• TikTok: https://www.tiktok.com/@ryanlpeterman

Referenced in this episode:

• PCP Theorem paper: https://www.cs.umd.edu/~gasarch/TOPICS/pcp/AS.pdf
• Paper on SAT approximation hardness: https://www.cs.umd.edu/~gasarch/BLOGPAPERS/max3satl.pdf
• Turing's paper: https://www.cs.virginia.edu/~robins/Turing_Paper_1936.pdf
• Original paper on NP completeness: https://www.cs.toronto.edu/~sacook/homepage/1971.pdf
• Ryan William's breakthrough result on space vs time: https://people.csail.mit.edu/rrw/time-vs-space.pdf
• Old result on space vs time: https://www-wjp.cs.uni-saarland.de/publikationen/HPV75.pdf
• Paper describing constant space majority solution: https://people.cs.umass.edu/~barring/publications/bwbp.pdf
• Fast primality test paper: https://www.sciencedirect.com/science/article/pii/0022314X80900840/pdf?md5=6f748cd82fa8efa1a637efab5f632baa&pid=1-s2.0-0022314X80900840-main.pdf
• Deterministic primality test paper: https://www.cse.iitk.ac.in/users/manindra/algebra/primality_v6.pdf
• Randomness vs observer paper: https://people.csail.mit.edu/silvio/Selected%20Scientific%20Papers/Pseudo%20Randomness/How_To_Generate_Cryptographically_Strong_Sequences_Of_Pseudo-Random_Bits.pdf
• Hardness vs randomness paper: https://www.math.ias.edu/~avi/PUBLICATIONS/MYPAPERS/NOAM/HARDNESS/final.pdf
• Erdos original sum vs product paper: https://users.renyi.hu/~p_erdos/1983-18.pdf
• Terrence Tao sum vs product paper: https://arxiv.org/pdf/math/0301343
• Seminal interactive proof paper: https://www.cs.miami.edu/home/burt/learning/csc609.221/goldwasser-micali-rackoff-knoweldge-complexity.pdf
• Zero knowledge proof paper: https://www.math.ias.edu/~avi/PUBLICATIONS/MYPAPERS/GMW86/GMW86.pdf
• Shor's algorithm original paper: https://arxiv.org/pdf/quant-ph/9508027
• Lattice paper (new hard problems): https://dl.acm.org/doi/epdf/10.1145/258533.258604
• MIP* vs RE paper: https://arxiv.org/pdf/2001.04383
• Zero knowledge non-interactive proofs: https://eprint.iacr.org/2025/1296.pdf

James Cowling is the CTO at Convex and was previously the most senior engineer at Dropbox. We discussed technical details of his past projects, simplicity vs complexity, and career advice given where AI is today.

• My ergonomic keyboard project I mentioned, you can follow along here: https://read.compose.llc/

Podcast links:

• YouTube: https://youtu.be/3XkmNSuHFmY
• Apple: https://podcasts.apple.com/us/podcast/the-peterman-pod/id1777363835
• Transcript: https://www.developing.dev/p/dropboxs-former-most-senior-eng-building

Thank you to this episode's sponsor for supporting my work:

• WorkOS: makes your app Enterprise Ready with easy to use APIs to add SSO, SCIM, RBAC, and more in just a few lines of code, check them out at https://workos.com/

Timestamps:

00:00:00 Intro
00:00:53 Systems work during his PhD
00:13:05 Dropbox technical deep dive
00:21:57 Why Dropbox migrated from AWS
00:36:40 How to do massive migrations
00:44:31 Simplicity vs complexity in promos
00:49:23 What technical teams should be focused on
01:00:25 Doing the right thing vs promo hypothetical
01:08:13 Why he dipped into management sometimes
01:11:36 Why you should not lead by example
01:23:23 How to mentor Senior Staff engineers
01:27:30 Career advice for the AI era
01:37:21 Why he started his own company
01:46:05 The most technically challenging work of his career
01:48:10 How he got involved in Silicon Valley
01:52:16 Career regrets
01:55:54 Top technical book recommendation
01:56:36 Younger self and permanent underclass advice

Where to find James:

• LinkedIn: https://www.linkedin.com/in/jcowling/
• Twitter/X: https://x.com/jamesacowling
• His company: https://www.convex.dev/

Where to find Ryan:

• Newsletter: https://www.developing.dev/
• X/Twitter: https://x.com/ryanlpeterman
• LinkedIn: https://www.linkedin.com/in/ryanlpeterman/
• Threads: https://www.threads.com/@ryanlpeterman
• Instagram: https://www.instagram.com/ryanlpeterman
• TikTok: https://www.tiktok.com/@ryanlpeterman

Referenced in this episode:

• His PhD Thesis: https://www.usenix.org/system/files/conference/atc12/atc12-final118.pdf
• Masters paper: https://www.cs.princeton.edu/courses/archive/fall19/cos418/papers/vr-revisited.pdf
• Papercuts writing he mentioned: https://medium.com/@jamesacowling/embracing-papercuts-e6390055dfc4
• "Don't lead by example": https://medium.com/@jamesacowling/dont-lead-by-example-4f86b1174e64
• His writing about orienting teams around missions: https://medium.com/@jamesacowling/your-system-is-not-a-sports-team-e17f9eb16b94