Adam Johnson

adamj.eu“Boost Your GitHub DX” out now - Adam JohnsonMy new book, Boost Your GitHub DX is out now!

11 Nov 2025

😸😸😸 Woohoo! My new book, Boost Your GitHub DX, is out now! 😸😸😸 It’s about using GitHub more effectively, touring you through the fundamental features with my experience-based commentary. Check out the release post for more info and a link to the free sample: adamj.eu/tech/2025/11... #GitHub #Git

adamj.euDjango: check version support with norwegianblue - Adam JohnsonDjango projects end up slotting into a bunch of software release cycles: Django itself, Python, database servers, cache servers, and more. It can be hard for us developers to keep track of all of them...

✍️ New post on using @hugovk.dev’s norwegianblue tool to check end-of-life dates relevant to Django developers. adamj.eu/tech/2026/10... #Django #Python

Adam Johnson reposted

Josh Tumath

@joshtumath.uk

Yesterday, the CSSWG accepted my proposal for mesh gradients and diffusion curve gradients! Want to make gradients like this natively in CSS? Well, we've started the work on it. It's coming! Here's the Explainer: github.com/w3c/csswg-dr...

adamj.euZsh: set aside a command with “Escape Q” / push-line - Adam JohnsonDo you ever do this? You carefully type out a command, like this pytest one:

✍️ New post on a neat Zsh feature for saving the command you’re currently typing for later, giving you room to run a setup command first. Handy for when you go “oops, that won’t work until I run X first”. adamj.eu/tech/2026/10... #Zsh

django-upgrade.readthedocs.ioChangelog - django-upgrade 1.33.0 documentation

🚄 Just released django-upgrade 1.33.0, now 27-38% faster! Three stacked optimizations led to a nice speedup. django-upgrade.readthedocs.io/en/latest/ch... #Django

adamj.euZsh: tab complete glob qualifiers - Adam JohnsonI’ve written a few posts on Zsh’s glob qualifiers recently, covering:

✍️ New post showing how Zsh’s autocompletion works even for small bits of syntax like glob qualifiers. Press Tab and see all the options, like “o” for ordering and “m” for modification time. adamj.eu/tech/2026/10... #Zsh

adamj.euDjango: serve apple-app-site-association and assetlinks.json - Adam JohnsonIf your site has companion Apple or Android apps, you probably want links to your site to open in those apps, when installed. Both platforms support this, with Apple calling the feature Universal Link...

✍️ New post on serving the Apple and Android app-to-site association files from Django. It can be fiddly to get the two sides interlinked! adamj.eu/tech/2026/10... #Django

adamj.euZsh: sort globs in natural order with the (n) glob qualifier - Adam JohnsonGlobs 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...

✍️ New post on Zsh’s natural sort order feature, handy for getting your pages in the right order! adamj.eu/tech/2026/09... #Zsh

For when crem doesn’t work:

adamj.euPython: join my meetup in Lisbon, 8th October - Adam JohnsonI 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.

📣 Join me on Thursday, 8th October, in Lisbon for a small software engineering meetup! Looking forward to meeting more folks out there. adamj.eu/tech/2026/09... #SoftwareEngineering #Python #Django #Lisbon #Lisboa #Portugal

adamj.euPython: join my optimization workshop in Lisbon, 10th October - Adam JohnsonI’m running a workshop in Lisbon next month, and you’re invited!

Still a few spots left!

Adam Johnson@adamj.eu

🔧 I’m excited to host this optimization workshop in Lisbon next month. Come join me to learn about profiling and optimizing Python code, and maybe even contribute to Django itself. adamj.eu/tech/2026/09... #Python #Django

adamj.euZsh: find the largest files with the (OL) glob qualifier - Adam JohnsonGot 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...

21 Sept

✍️ New post on finding big files with Zsh’s glob qualifiers adamj.eu/tech/2026/09... #Zsh

youtube.comS.P.Y - What The Future Holds (feat. Ian Shaw) - OFFICIAL VIDEOYouTube video by Hospital Records

21 Sept

🔊 What the Future Holds - S.P.Y. Gorgeous orchestral dnb, amazing London timelapses, still hits big 14 years later. www.youtube.com/watch?v=-X07... #DrumAndBass #London

adamj.eumacOS: use caffeinate to keep your computer on - Adam JohnsonIf 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...

20 Sept

✍️ New post on using macOS’ caffeinate command, which I recently found useful to keep a code migration script running. adamj.eu/tech/2026/09... #macOS

Adam Johnson reposted

Frank Wiles

@fwiles.bsky.social

19 Sept

Made a fun little utility for myself over the last hour or so. Using Adam Johnson's new django-mcpz created an MCP in my personal cluster to collect "notes" and then an iOS shortcut to launch Claude in voice chat mode so I can add/edit/retrieve notes while on the go

adamj.euPython: join my optimization workshop in Lisbon, 10th October - Adam JohnsonI’m running a workshop in Lisbon next month, and you’re invited!

19 Sept

adamj.euDjango: serve the change password well-known URL - Adam JohnsonWhen 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...

16 Sept

✍️ New post on serving the change password well-known URL in Django Add this one redirect and two tests (you won't believe #2) to make your site more user-friendly for users with compromised passwords. adamj.eu/tech/2026/09... #Django #Security

github.comunittest-parametrize/CHANGELOG.rst at main · adamchainz/unittest-parametrizeParametrize tests within unittest TestCases. Contribute to adamchainz/unittest-parametrize development by creating an account on GitHub.

16 Sept

🧪 I just released unittest-parametrize 1.9.0. This package helps you make parametrized tests that work with the grain of unittest, but can still be run with pytest. github.com/adamchainz/u... #Python

16 Sept

This release adds new skip/expected_failure features, fixes a bug when using Coverage\.py's dynamic contexts, and tidies up error messages and usage docs.

adamj.euDjango: introducing django-mcpz, for making MCP servers - Adam JohnsonI made another package! Say hello to django-mcpz, for building Model Context Protocol (MCP) servers in your Django project.

15 Sept

🎁 Introducing django-mcpz: easy peasy MCP servers in Django! This new package lets you build an MCP server in your Django project, letting LLMs do things on your site on behalf of your users. adamj.eu/tech/2026/09... #Django #AI

Adam Johnson reposted

Simon Willison

@simonwillison.net

14 Sept

Built a little local web app to help edit commit messages for a repo simonwillison.net/2026/Sep/14/...

time-machine.readthedocs.ioChangelog - time-machine 3.5.1 documentation

8 Sept

⏳ I just released time-machine 3.5.1 with 13 bug fixes. Two were reported by humans. The rest came from prompting Claude Fable with just "Find and fix bugs". time-machine.readthedocs.io/en/latest/ch...

8 Sept

None of them had a huge impact (this is a test library, after all), but they were all mistakes. The worst would leave time mocked after a test tearDownClass() failure, which would be pretty hard to debug. Crazy times. These machines can help us build the highest-quality software, if we want.

pypi.orgpytest-randomlyPytest plugin to randomly order tests and control random.seed.

1 Sept

🎲 Just released pytest-randomly 5.0.0 The headline breaking change fixes combination with other test reordering plugins, including pytest-django. Previously, the same seed could produce different test orders between nearly-identical environments. Oops! #Python #pytest pypi.org/project/pyte...

1 Sept

Software is never finished: even this 11 year old well-scoped plugin needs the occasional big fix!

adamj.euZsh: manipulate filenames with modifiers like :r (root) and :e (extension) - Adam JohnsonZsh 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 ...

24 Aug

✍️ Zsh lets you manipulate filenames with modifiers, which I recently found useful when converting files between formats. adamj.eu/tech/2026/08... #Zsh

We’re so back #htmx

✍️ I used my leet prompt engineering skillz to fix a bunch of bugs in django-upgrade adamj.eu/tech/2026/08... #Django #Python #AI

adamj.euDjango: django-upgrade 1.32.0 out now, with 44 AI-assisted bug fixes - Adam Johnsondjango-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...

Adam Johnson reposted

Christopher Trudeau

@trudeau.dev

14 Aug

On this week's episode, @digiglean.bsky.social and I talk about testing in Django, SIMD, data visualization and more. With content from: @djangoproject.com @adamj.eu @retr0.id @purplesyringa.bsky.social and others not on the 🦋 Also, this time I might even include a link! buff.ly/rTT0o1M

realpython.comEpisode #307: Improving NumPy Performance on Free-Threaded Python – The Real Python PodcastWhat 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.

adamj.euPython: introducing emojet, a fast emoji lookup library - Adam JohnsonNew package just landed!

12 Aug

📦 New package day! This time a Rusty rewrite of the emoji package: 3.5x faster for conversion, 70 times faster for deconversion, and using about 40% less memory. adamj.eu/tech/2026/08... #Python #Rust

adamj.euPython: tprof 1.3.0: now with less overhead - Adam JohnsonBack 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...

8 Aug

✍️ I just released a new version of my little Python profiler, tprof, with less overhead for more accurate results. adamj.eu/tech/2026/08... #Python

7 Aug

🎨 I’m really enjoying the redesigned PyPI project pages. Thanks to Nicole Harris and team for making these improvements! Blog post: blog.pypi.org/posts/2026-0... #Python

adamj.euDjango: introducing django-msgspec - Adam JohnsonIt’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.

7 Aug

✍️ New package: django-msgspec, providing Django integrations with msgspec’s faster JSON serialization and deserialization. adamj.eu/tech/2026/08... #Django

adamj.euGit: my git stash -p optimization in Git 2.55 - Adam JohnsonI got another commit merged in Git 2.55 (2026-06-29), yay! The release note reads:

7 Aug

✍️ The story of a 50x optimization I made in Git earlier this year. adamj.eu/tech/2026/08... #Git

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

6 Aug

✍️ List the files present in any Git commit without checking it out. adamj.eu/tech/2026/08... #Git

6 Aug

😍 wowza

Ellie Huxtable@ellie.wtf

coming in atuin v18.20 🐢✨ autocomplete, from your shell history with support for standard shell completions!

django-htmx.readthedocs.ioChangelog - django-htmx 1.29.0 documentation

📦 Just released django-htmx 1.29.0 which now vendors a bunch of htmx extensions, updates the vendored htmx versions, and adds support for htmx v4's polling extension django-htmx.readthedocs.io/en/latest/ch... #Django #htmx

adamj.euPython: sharing common tests in unittest - Adam JohnsonA 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...

🆙 Updated my post on unittest base test cases with a new preferred technique: using a plain class as a container. adamj.eu/tech/2025/05... #Python #unittest

adamj.euGit: exclude commits by an author in git log with --perl-regexp - Adam Johnsongit log has an --author option to limit the output to commits from matching authors:

✍️ New post covering how to read your local Git log while skipping commits from a certain author. In my case, it was the ol’ Dependabot. adamj.eu/tech/2026/08... #Git #GitHub

djangoproject.comDjango 6.1 releasedPosted by Jacob Walls on Aug. 5, 2026

Django 6.1 is out !!! www.djangoproject.com/weblog/2026/... #Django

adamj.euZsh: list recently modified files with (m0) glob qualifiers - Adam JohnsonMy 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.

4 Aug

✍️ A neat trick I learned using Zsh to list recently modified files. adamj.eu/tech/2026/08... #Zsh

adamj.euPython: how time-machine is O(1) where freezegun is O(n) - Adam Johnsontime-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.

3 Aug

✍️ New post demonstrating the runtime advantage of my package time-machine over its inspiration, freezegun. adamj.eu/tech/2026/08... #Python

Adam Johnson reposted

Hugo van Kemenade

@hugovk.dev

3 Aug

"Python has decided to enable frame pointers by default and encourage the ecosystem to do so as well, to make debugging easier for us all, so time-machine is joining the party." Enabled by default for 3.15, do this for older versions: github.com/adamchainz/t... #Python

github.comBuild with frame pointers enabled by adamchainz · Pull Request #627 · adamchainz/time-machine

Adam Johnson@adamj.eu

✍️ time-machine 3.3.0 is out, with Python 3.15 support, performance improvements, subinterpreter support, and various bug fixes. Check it out, and if you’re using freezegun, try the updated Migration CLI to convert and speed up your tests. adamj.eu/tech/2026/07... #Python

adamj.euPython: time-machine 3.3.0 lets your tests time-travel even faster - Adam Johnsontime-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.

Adam Johnson reposted

Jake Howard 🍊

@theorangeone.net

31 July

I replaced linkchecker with @adamj.eu's django-crawl on my website. Shaved 2 minutes off my CI time, with a fancy UI, fewer bodges, and a sprinkling of #rust for good measure 🙌 github.com/adamchainz/d...

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

What do you see?

Made with Decoy Font www.mixfont.com/experiments/...

mixfont.comDecoy Font: A TTF font that hides what you typeDecoy Font combines every letter with a decoy, making it harder for AI to read what you type. Type a message to try it out or download the TTF directly.

27 July

big horse energy

htmx.org / CEO of Java Pants@htmx.org

gameboy game trailer

adamj.euPython: inspect unittest.mock calls with attached mocks - Adam JohnsonWhen 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...

27 July

✍️ New post on a Python testing technique: inspecting interleaved calls across multiple mocks with attached mocks. #Python adamj.eu/tech/2026/07...

adamj.euPython: spy on function calls with unittest.mock’s wraps - Adam JohnsonTesting terminology distinguishes between different kinds of test doubles, including:

25 July

✍️ New post on using unittest.mock to spy on function calls. 🕵️‍♂️ I recently learned how to use the wraps argument to track calls to a target function for later assertions. Handy for testing things like “is caching working?” without mocking the function completely. #Python adamj.eu/tech/2026/07...