Adam Johnson

⏳ 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".

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.

#Python

https://time-machine.readthedocs.io/en/latest/changelog.html

🎁 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.

https://adamj.eu/tech/2026/09/15/introducing-django-mcpz/

#Django #AI

RE: @MrJico@infosec.exchange

Great post on the cost and timing of decisions.

Thanks @GitRon@mastodon.social

> This is why we start with Django. Not because it is the best framework in some abstract sense, but because it comes with a working default for everything that is not business logic...

#Django

🎲 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!

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

#Python #pytest #Django

https://pypi.org/project/pytest-randomly/

✍️ New post on using unittest.mock to spy on function calls. 🕵️‍♂️

I recently learned how to use the wraps argument to track all calls to a target function for later assertions. Very useful for testing things like “is caching working?” without having to mock the function completely.

#Python

https://adamj.eu/tech/2026/07/25/python-spy-unittest-mock-wraps/

✍️ Django’s release code words, up to the pending Django 6.1 “mélange”.

https://adamj.eu/tech/2026/07/24/django-release-code-words-6.1/

#Python #Django

@mahryekuh@hachyderm.io I know the approach has issues like your one, and no I don’t have a fix. I think the pytest-Django features works similarly to what my blog post describes so not sure what you’re seeing is different.

I do think we could overhaul the whole missing variable system to copy from Jinja. Rather than detecting missing variables when named, it substitutes them with a special object that raises an error it logs something when rendered. But I’ve not had time to formalise this proposal.

What do you see?

✍️ New post on a Python testing technique: inspecting interleaved calls across multiple mocks with attached mocks.

#Python

https://adamj.eu/tech/2026/07/27/python-mock-attach-mock/

✍️ New post detailing a workaround I came up with for “leak” beahviour from Python 3.14’s new garbage collection algorithm.

Topical as @hugovk@mastodon.social recently announced that the algorithm will be reverted in the next patch release!

https://adamj.eu/tech/2026/04/20/django-python-3.14-incremental-gc/

#Django #Python

✍️ Introducing django-crawl, a tool for crawling your local Django site, useful for quickly finding what’s broken or performing site-wide checks.

https://adamj.eu/tech/2026/07/22/introducing-django-crawl/

#Django #Python

✍️ New post introducing profiling-explorer, a tool for exploring Python profiling data (pstats files).

Use it with the classic cProfile (now called profiling.tracing) or Python 3.15’s new sampling profiler, Tachyon (profiling.sampling).

https://adamj.eu/tech/2026/04/03/python-introducing-profiling-explorer/

#Python

I've just done a pass over a client project with deptry, and it worked great for finding unused dependencies!

https://deptry.com/

#Python

RE: @wsvincent@fosstodon.org

🐛 let the bugs crawl to you…