uv/crates/uv-python
Aria Desires 317ce6e245
disfavor aarch64 windows in its own house (#13724)
and prefer emulated x64 windows in its stead.

This is preparatory work for shipping support for uv downloading and
installing aarch64 (arm64) windows Pythons. We've [had builds for this
platform ready for a
while](https://github.com/astral-sh/python-build-standalone/pull/387),
but have held back on shipping them due to a fundamental problem:

**The Python packaging ecosystem does not have strong support for
aarch64 windows**, e.g., not many projects build aarch64 wheels yet. The
net effect of this is that, if we handed you an aarch64 python
interpreter on windows, you would have to build a lot more sdists, and
there's a high chance you will simply fail to build that sdist and be
sad.

Yes unfortunately, in this case a non-native Python interpreter simply
*works better* than the native one... in terms of working at all, today.
Of course, if the native interpreter works for your project, it should
presumably have better performance and platform compatibility.

We do not want to stand in the way of progress, as ideally this
situation is a temporary state of affairs as the ecosystem grows to
support aarch64 windows. To enable progress, on aarch64 Windows builds
of uv:

* We will still use a native python interpreter, e.g., if it's at the
front of your `PATH` or the only installed version.
* If we are choosing between equally good interpreters that differ in
architecture, x64 will be preferred.
* If the aarch64 version is newer, we will prefer the aarch64 one.
* We will emit a diagnostic on installation, and show the python request
to pass to uv to force aarch64 windows to be used.
* Will be shipping [aarch64 Windows Python
downloads](https://github.com/astral-sh/python-build-standalone/pull/387)
* Will probably add some kind of global override setting/env-var to
disable this behaviour.
* Will be shipping this behaviour in
[astral-sh/setup-uv](https://github.com/astral-sh/setup-uv)

We're coordinating with Microsoft, GitHub (for the `setup-python`
action), and the CPython team (for the `python.org` installers), to
ensure we're aligned on this default and the timing of toggling to
prefer native distributions in the future.

See discussion in 

- https://github.com/astral-sh/uv/issues/12906

---

This is an alternative to 

* #13719 

which uses sorting rather than filtering, as discussed in 

* #13721
2025-06-30 17:42:00 -04:00
..
python Fix Ruff linting (#14111) 2025-06-17 17:28:23 +00:00
src disfavor aarch64 windows in its own house (#13724) 2025-06-30 17:42:00 -04:00
.gitignore minify and filter embed managed pythons json on compile time (#12967) 2025-04-30 15:51:03 -04:00
build.rs Only rebuild download JSON on change (#13261) 2025-05-02 07:49:34 -05:00
Cargo.toml Support transparent Python patch version upgrades (#13954) 2025-06-20 16:17:13 +02:00
download-metadata.json Bump python-build-standalone releases to include 3.14.0b3 (#14301) 2025-06-27 12:36:07 -05:00
fetch-download-metadata.py Fix Ruff linting (#14111) 2025-06-17 17:28:23 +00:00