Simon Willison

Python 3.15.0 added to actions/python-versions

Python 3.15.0 has been added to the actions/python-versions repository. The author had been monitoring the repository for the release and used ChatGPT to automate the check. With the new version available, users can now include "3.15" in their GitHub Actions testing matrix to run tests against the latest Python release.

Simon Willison
Sep 1

Python 3.15.0 candidate 2 is here!

Python 3.15.0 candidate 2 has been released, marking the final release candidate for the upcoming 3.15 release scheduled for October. Hugo van Kemenade, the release manager, notes that only clear bug‑fix changes are allowed between this candidate and the final release, and urges third‑party maintainers to prepare wheels on PyPI and test their projects during this phase. The new RC is not yet available for GitHub Actions, but users can add it to their testing matrix using the allow‑prereleases and check‑latest flags to automatically test against the latest RC and then the stable release.

Simon Willison
Aug 24

llm-anthropic 0.27

The release of llm‑anthropic 0.27 updates the Anthropic plugin for LLM to be compatible with the newly released anthropic v1.0.0 Python library, which has switched from httpx to httpx2. This mirrors a similar change made by OpenAI in their v3.0.0 release two weeks prior. The update includes a migration guide and a pull request that ensures tests pass after upgrading to anthropic>=1.

Simon Willison
Aug 25

EVE Online: The Move to Python 3 Begins!

EVE Online is beginning its transition to Python 3, a move that will involve using the futurize script on 2.4 million lines of code and a manual review of about 20,000 differences between Python 2 and Python 3. The company has historically run on Stackless Python since 2003, with the last major upgrade in 2010 to Stackless Python 2.7. While the announcement does not detail how Stackless will be replaced, the team previously showcased a shift away from Stackless in their Carbon engine for EVE Frontier, leveraging the open‑source carbonengine/scheduler library.

Simon Willison
Oct 12

Hello Python 3.15, goodbye 3.10, and now I can use 3.11

Python 3.15 introduces several new features, notably explicit lazy imports from PEP 810 that delay module loading until first use, and unpacking syntax in comprehensions (PEP 798) that simplifies flattening lists, sets, and dictionaries. The release also updates the profiling tools, renaming the tracing profiler to profiling.tracing and adding a new sampling profiler, profiling.sampling. These changes aim to improve performance and developer ergonomics in Python code.

Simon Willison
Aug 9

GitHub Models is now retired

GitHub Models is now retired I missed this news until today, when the GitHub Actions run for my simonw/research repository failed with this error message: GitHub Models is temporarily unavailable as part of a scheduled retirement brownout. That message is already stale, because the retirement has been completed.

Simon Willison
Sep 10

Any Nix package, live in your browser

Farid Zakaria’s trynix.dev lets users run any Nix package from the past 13 years inside a browser‑based x86_64 Linux VM powered by QEMU‑WASM. By providing URL‑addressable packages, a user can simply navigate to a link such as https://trynix.dev/?pkg=python3%403.6.2, click "Load," and obtain an interactive shell running that specific package. The platform is also integrated with GitHub Actions, enabling pull‑request reviews that launch the PR’s build directly in the browser via trynix-preview.

Simon Willison
Oct 13

web-edit 0.1a1

The article announces the release of web-edit version 0.1a1. It highlights performance optimizations that were written by Claude Opus 5.5, which were generated after feeding it a Python 3.15 profiling report created by GPT‑6 Astra. The release is tagged with "profiling" and "projects".

Simon Willison
Oct 1

pwasm 0.2a0

Release: pwasm 0.2a0 pwasm is one of my folly projects - an entirely vibe-coded pure Python WebAssembly engine that I built in January during my first bout of AI mania. I hadn't touched it sin...

Simon Willison
Aug 22

llm 0.33

The release of llm 0.33 introduces several key updates: it upgrades to the OpenAI Python library 3.x and switches the HTTP client from httpx to httpx2, adds comprehensive key handling for embedding functions, allows repeated template usage to combine configurations, and adds a reasoning_summary option for reasoning-capable responses. These changes improve compatibility, flexibility, and usability of the llm tool.

Simon Willison
Sep 18

Quoting Thariq Shihipar

The article announces that Claude Code will now support AGENTS.md files starting with version 2.1.277. If a CLAUDE.md file is absent in a folder, Claude will automatically look for and use AGENTS.md, leveraging Claude Code mods to customize the harness. The built‑in mod is available for use, and users can also create their own custom project instructions.