February 09, 2026

#469 Commands, out of the terminal

33 minutes

Topics covered in this episode:

Command Book App

uvx.sh: Install Python tools without uv or Python

Ending 15 years of subprocess polling

monty: A minimal, secure Python interpreter written in Rust for use by AI

Extras

Joke

Watch on YouTube

About the show

Sponsored by us! Support our work through:

Our courses at Talk Python Training

The Complete pytest Course

Patreon Supporters

Connect with the hosts

Michael: @[email protected] / @mkennedy.codes (bsky)

Brian: @[email protected] / @brianokken.bsky.social

Show: @[email protected] / @pythonbytes.fm (bsky)

Join us on YouTube at pythonbytes.fm/live to be part of the audience. Usually Monday at 10am PT. Older video versions available there too.

Finally, if you want an artisanal, hand-crafted digest of every week of the show notes in email form? Add your name and email to our friends of the show list, we'll never share it.

Michael #1: Command Book App

New app from Michael

Command Book App is a native macOS app for developers, data scientists, AI enthusiasts and more.

This is a tool I've been using lately to help build Talk Python, Python Bytes, Talk Python Training, and many more applications.

It's a bit like advanced terminal commands or complex shell aliases, but hosted outside of your terminal. This leaves the terminal there for interactive commands, exploration, short actions.

Command Book manages commands like "tail this log while I'm developing the app", "Run the dev web server with true auto-reload", and even "Run MongoDB in Docker with exactly the settings I need"

I'd love it if you gave it a look, shared it with your team, and send me feedback.

Has a free version and paid version.

Build with Swift and Swift UI

Check it out at https://commandbookapp.com

Brian #2: uvx.sh: Install Python tools without uv or Python

Tim Hopper

Michael #3: Ending 15 years of subprocess polling

by Giampaolo Rodola

The standard library's subprocess module has relied on a busy-loop polling approach since the timeout parameter was added to Popen.wait() in Python 3.3, around 15 years ago

The problem with busy-polling

CPU wake-ups: even with exponential backoff (starting at 0.1ms, capping at 40ms), the system constantly wakes up to check process status, wasting CPU cycles and draining batteries.

Latency: there's always a gap between when a process actually terminates and when you detect it.

Scalability: monitoring many processes simultaneously magnifies all of the above.

+ L1/L2 CPU cache invalidations

It’s interesting to note that waiting via poll() (or kqueue()) puts the process into the exact same sleeping state as a plain time.sleep() call. From the kernel's perspective, both are interruptible sleeps.

Here is the merged PR for this change.

Brian #4: monty: A minimal, secure Python interpreter written in Rust for use by AI

Samuel Colvin and others at Pydantic

Still experimental

“Monty avoids the cost, latency, complexity and general faff of using a full container based sandbox for running LLM generated code. “

“Instead, it lets you safely run Python code written by an LLM embedded in your agent, with startup times measured in single digit microseconds not hundreds of milliseconds.”

Extras

Brian:

Expertise is the art of ignoring - Kevin Renskers

You don’t need to master the language. You need to master your slice.

Learning everything up front is wasted effort.

Experience changes what you pay attention to.

I hate fish - Rands (Michael Lopp)

Really about productivity systems

And a nice process for dealing with email

Michael:

Talk Python now has a CLI

New essay: It's not vibe coding - Agentic engineering

GitHub is having a day

Python 3.14.3 and 3.13.12 are available

Wall Street just lost $285 billion because of 13 markdown files

Joke: Silence, current side project!

...more

View all episodes

By Michael Kennedy and Brian Okken

4.7

212212 ratings

February 09, 2026

#469 Commands, out of the terminal

33 minutes

Topics covered in this episode:

Command Book App

uvx.sh: Install Python tools without uv or Python

Ending 15 years of subprocess polling

monty: A minimal, secure Python interpreter written in Rust for use by AI

Extras

Joke

Watch on YouTube

About the show

Sponsored by us! Support our work through:

Our courses at Talk Python Training

The Complete pytest Course

Patreon Supporters

Connect with the hosts

Michael: @[email protected] / @mkennedy.codes (bsky)

Brian: @[email protected] / @brianokken.bsky.social

Show: @[email protected] / @pythonbytes.fm (bsky)

Join us on YouTube at pythonbytes.fm/live to be part of the audience. Usually Monday at 10am PT. Older video versions available there too.

Finally, if you want an artisanal, hand-crafted digest of every week of the show notes in email form? Add your name and email to our friends of the show list, we'll never share it.

Michael #1: Command Book App

New app from Michael

Command Book App is a native macOS app for developers, data scientists, AI enthusiasts and more.

This is a tool I've been using lately to help build Talk Python, Python Bytes, Talk Python Training, and many more applications.

It's a bit like advanced terminal commands or complex shell aliases, but hosted outside of your terminal. This leaves the terminal there for interactive commands, exploration, short actions.

Command Book manages commands like "tail this log while I'm developing the app", "Run the dev web server with true auto-reload", and even "Run MongoDB in Docker with exactly the settings I need"

I'd love it if you gave it a look, shared it with your team, and send me feedback.

Has a free version and paid version.

Build with Swift and Swift UI

Check it out at https://commandbookapp.com

Brian #2: uvx.sh: Install Python tools without uv or Python

Tim Hopper

Michael #3: Ending 15 years of subprocess polling

by Giampaolo Rodola

The standard library's subprocess module has relied on a busy-loop polling approach since the timeout parameter was added to Popen.wait() in Python 3.3, around 15 years ago

The problem with busy-polling

CPU wake-ups: even with exponential backoff (starting at 0.1ms, capping at 40ms), the system constantly wakes up to check process status, wasting CPU cycles and draining batteries.

Latency: there's always a gap between when a process actually terminates and when you detect it.

Scalability: monitoring many processes simultaneously magnifies all of the above.

+ L1/L2 CPU cache invalidations

Here is the merged PR for this change.

Brian #4: monty: A minimal, secure Python interpreter written in Rust for use by AI

Samuel Colvin and others at Pydantic

Still experimental

“Monty avoids the cost, latency, complexity and general faff of using a full container based sandbox for running LLM generated code. “

“Instead, it lets you safely run Python code written by an LLM embedded in your agent, with startup times measured in single digit microseconds not hundreds of milliseconds.”

Extras

Brian:

Expertise is the art of ignoring - Kevin Renskers

You don’t need to master the language. You need to master your slice.

Learning everything up front is wasted effort.

Experience changes what you pay attention to.

I hate fish - Rands (Michael Lopp)

Really about productivity systems

And a nice process for dealing with email

Michael:

Talk Python now has a CLI

New essay: It's not vibe coding - Agentic engineering