Topics covered in this episode:

git-flight-rules
Uravelling t-strings
neohtop
Introducing Pyrefly: A new type checker and IDE experience for Python
Extras
Joke

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Michael #1: git-flight-rules

What are "flight rules"?
- A guide for astronauts (now, programmers using Git) about what to do when things go wrong.
- Flight Rules are the hard-earned body of knowledge recorded in manuals that list, step-by-step, what to do if X occurs, and why. Essentially, they are extremely detailed, scenario-specific standard operating procedures. [...]
- NASA has been capturing our missteps, disasters and solutions since the early 1960s, when Mercury-era ground teams first started gathering "lessons learned" into a compendium that now lists thousands of problematic situations, from engine failure to busted hatch handles to computer glitches, and their solutions.
Steps for common operations and actions
- I want to start a local repository
- What did I just commit?
- I want to discard specific unstaged changes
- Restore a deleted file

Brian #2: Uravelling t-strings

Brett Cannon
Article walks through
- Evaluating the Python expression
- Applying specified conversions
- Applying format specs
- Using an Interpolation class to hold details of replacement fields
- Using Template class to hold parsed data
Plus, you don’t have to have Python 3.14.0b1 to try this out.
The end result is very close to an example used in PEP 750, which you do need 3.14.0b1 to try out.
See also:
- I’ve written a pytest version, Unravelling t-strings with pytest, if you want to run all the examples with one file.

Michael #3: neohtop

Blazing-fast system monitoring for your desktop
Features
- Real-time process monitoring
- CPU and Memory usage tracking
- Beautiful, modern UI with dark/light themes
- Advanced process search and filtering
- Pin important processes
- Process management (kill processes)
- Sort by any column
- Auto-refresh system stats

Brian #4: Introducing Pyrefly: A new type checker and IDE experience for Python

From Facebook / Meta
Another Python type checker written in Rust
Built with IDE integration in mind from the beginning
Principles
- Performance
- IDE first
- Inference (inferring types in untyped code)
- Open source
I mistakenly tried this on the project I support with the most horrible abuses of the dynamic nature of Python, pytest-check. It didn’t go well. But perhaps the project is ready for some refactoring. I’d like to try it soon on a more well behaved project.

Extras

Brian:

Python: The Documentary Official Trailer
Tim Hopper added Setting up testing with ptyest and uv to his “Python Developer Tooling Handbook”
For a more thorough intro on pytest, check out courses.pythontest.com
pocket is closing, I’m switching to Raindrop
- I got one question about code formatting. It’s not highlighted, but otherwise not bad.

Michael:

New course! Polars for Power Users: Transform Your Data Analysis Game
Apache Airflow 3.0 Released
Paste 5

Joke: Theodore Roosevelt’s Man in the Arena, but for programming

#433 Dev in the Arena

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