Globs sort filenames character by character, so numbered files often come out in a surprising order, with 10 before 2. Zsh has a neat fix for this: the n glob qualifier, which applies a “natural” sort...

I previously announced my Python optimization workshop in Lisbon, on 10th October (which still has a few places). I am now pleased to add a Python/Django meetup on the Thursday before.

Got a directory that you want to tidy up bloat from? Whether you’re trying to find bad build artifacts in your work repository or clear out old cat videos from your home directory, Zsh’s (OL) glob qua...

YouTube video by Hospital Records

If you’re starting a long job on your Apple Macintosh Computer and wandering off for a coffee, the machine may go to sleep before it finishes due to inactivity. To prevent that from happening, also gi...

I’m running a workshop in Lisbon next month, and you’re invited!

When a password manager detects that a user’s password has been leaked or reused, it can prompt them to change it, but the password change URL varies by site. The web’s answer to such discovery proble...

Parametrize tests within unittest TestCases. Contribute to adamchainz/unittest-parametrize development by creating an account on GitHub.

I made another package! Say hello to django-mcpz, for building Model Context Protocol (MCP) servers in your Django project.

Pytest plugin to randomly order tests and control random.seed.

Zsh modifiers are a family of suffixes that transform words as they’re expanded. Several of them are dedicated to slicing up filenames, replacing fiddly calls to dirname, basename, and friends. Let’s ...

django-upgrade is my tool for automatically upgrading your project code for new Django versions. It rewrites your Python files to fix deprecations and adopt some new features, taking a chunk of the mo...

What bottlenecks were preventing NumPy from scaling on free-threaded Python? Christopher Trudeau is back on the show this week with another batch of PyCoder's Weekly articles and projects.

New package just landed!

Back in January, I introduced tprof, a targeting profiler for Python 3.12+ that measures the time spent in specific functions, rather than your whole program. As a reminder, here’s the basic usage, sp...

It’s another day, another new package day here. Say hello to django-msgspec, a package of drop-in replacements for Django and Django REST Framework (DRF) components backed by msgspec.

I got another commit merged in Git 2.55 (2026-06-29), yay! The release note reads:

To list all files in your repository as they were at a given commit, use git ls-tree with its -r and --name-only options:

A neat testing pattern is writing common tests in a base class and then applying them to multiple objects through subclassing. Doing so can help you test smarter and cover more code with less boilerpl...

git log has an --author option to limit the output to commits from matching authors:

Posted by Jacob Walls on Aug. 5, 2026

My downloads directory is a junk pile that I just never get around to fully clearing. So if I’ve just downloaded a bunch of files, I normally want to work with them and ignore the rest of the files.

time-machine is my library for mocking the current date and time in Python tests. Its headline advantage over freezegun, the library that inspired it, is speed.

An in-process site crawler using Django’s test client. - adamchainz/django-crawl

time-machine is my library for mocking the current date and time in Python tests. I’ve just released version 3.3.0 with a decent number of changes, so here’s a lovely summary for you.

When you use a unittest.mock mock, you often make assertions on the calls it received, such as through the mock_calls list. But sometimes you want to assert on the order of calls across multiple mocke...

Testing terminology distinguishes between different kinds of test doubles, including:

Did you know that each Django release has a “code word” associated with it? It’s hidden in plain sight, in the announcement blog post describing the list of features coming in the next version. I thin...

I recently migrated one of my client projects from the legacy django-csp package to Django 6.0’s built-in Content Security Policy (CSP) support (release note). This security header is a powerful tool ...

Just as cars painted red are known to be faster, libraries implemented in Rust are also known to be faster. Today’s example is orjson, a Rusty replacement for Python’s built-in json module, boasting 1...

Here’s a lovely hack that I’ve used when machete-mode debugging.

In several programs, I’ve wanted to solve the problem of associating extra data with an object. For example, in django-upgrade, the individual “fixer” functions often want to store extra data per visi...

Back in January, Firefox’s Security & Privacy Newsletter for 2025 Q4 piqued my interest with this mention:

What if you could build charts in Python by describing what your data means, instead of scripting every visual detail? Christopher Trudeau is back on the show this week with another batch of…

Back in February, I encountered an out-of-memory error while migrating a client project to Python 3.14. The issue occurred when running Django’s database migration command (migrate) on a limited-resou...

I’ve made another package! Like icu4py, which I made in February, it was sponsored by my client Rippling. And like tprof, which I made in January, it’s a profiling tool!