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Comment by notatallshaw

10 days ago

> uv pip install --system torch torchvision torchaudio --index-url https://download.pytorch.org/whl/cu118

uv has a feature to get the correct version of torch based on your available cuda (and some non-cuda) drivers (though I suggest using a venv not the system Python):

> uv pip install torch torchvision torchaudio --torch-backend=auto

More details: https://docs.astral.sh/uv/guides/integration/pytorch/#automa...

This also means you can safely mix torch requirements with non-torch requirements as it will only pull the torch related things from the torch index and everything else from PyPI.

5 comments

notatallshaw

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xrd  10 days ago

I love uv and really feel like I only need to know "uv add" and "uv sync" to be effective using it with python. That's an incredible feat.

But, when I hear about these kinds of extras, it makes me even more excited. Getting cuda and torch to work together is something I have struggled countless times.

The team at Astral should be nominated for a Nobel Peace Prize.

  • danudey  10 days ago

    > "uv add"

    One life-changing thing I've been using `uv` for:

    System python version is 3.12:

        $ python3 --version
    Python 3.12.3

    A script that requires a library we don't have, and won't work on our local python:

        $ cat test.py
    #!/usr/bin/env python3

    import sys
    from rich import print

    if sys.version_info < (3, 13):
        print("This script will not work on Python 3.12")
    else:
        print(f"Hello world, this is python {sys.version}")

    It fails:

        $ python3 test.py
    Traceback (most recent call last):
    File "/tmp/tmp/test.py", line 10, in <module>
        from rich import print
    ModuleNotFoundError: No module named 'rich'

    Tell `uv` what our requirements are

        $ uv add --script=test.py --python '3.13' rich
    Updated `test.py`

    `uv` updates the script:

        $ cat test.py
    #!/usr/bin/env python3
    # /// script
    # requires-python = ">=3.13"
    # dependencies = [
    #     "rich",
    # ]
    # ///

    import sys
    from rich import print

    if sys.version_info < (3, 13):
        print("This script will not work on Python 3.12")
    else:
        print(f"Hello world, this is python {sys.version}")

    `uv` runs the script, after installing packages and fetching Python 3.13

        $ uv run test.py
    Downloading cpython-3.13.5-linux-x86_64-gnu (download) (33.8MiB)
    Downloading cpython-3.13.5-linux-x86_64-gnu (download)
    Installed 4 packages in 7ms
    Hello world, this is python 3.13.5 (main, Jun 12 2025, 12:40:22) [Clang 20.1.4 ]

    And if we run it with Python 3.12, we can see that errors:

        $ uv run --python 3.12 test.py
    warning: The requested interpreter resolved to Python 3.12.3, which is incompatible with the script's Python requirement: `>=3.13`
    Installed 4 packages in 7ms
    This script will not work on Python 3.12

    Works for any Python you're likely to want:

        $ uv python list
    cpython-3.14.0b2-linux-x86_64-gnu                 <download available>
    cpython-3.14.0b2+freethreaded-linux-x86_64-gnu    <download available>
    cpython-3.13.5-linux-x86_64-gnu                   /home/dan/.local/share/uv/python/cpython-3.13.5-linux-x86_64-gnu/bin/python3.13
    cpython-3.13.5+freethreaded-linux-x86_64-gnu      <download available>
    cpython-3.12.11-linux-x86_64-gnu                  <download available>
    cpython-3.12.3-linux-x86_64-gnu                   /usr/bin/python3.12
    cpython-3.12.3-linux-x86_64-gnu                   /usr/bin/python3 -> python3.12
    cpython-3.11.13-linux-x86_64-gnu                  /home/dan/.local/share/uv/python/cpython-3.11.13-linux-x86_64-gnu/bin/python3.11
    cpython-3.10.18-linux-x86_64-gnu                  /home/dan/.local/share/uv/python/cpython-3.10.18-linux-x86_64-gnu/bin/python3.10
    cpython-3.9.23-linux-x86_64-gnu                   <download available>
    cpython-3.8.20-linux-x86_64-gnu                   <download available>
    pypy-3.11.11-linux-x86_64-gnu                     <download available>
    pypy-3.10.16-linux-x86_64-gnu                     <download available>
    pypy-3.9.19-linux-x86_64-gnu                      <download available>
    pypy-3.8.16-linux-x86_64-gnu                      <download available>
    graalpy-3.11.0-linux-x86_64-gnu                   <download available>
    graalpy-3.10.0-linux-x86_64-gnu                   <download available>
    graalpy-3.8.5-linux-x86_64-gnu                    <download available>

  • j45  10 days ago

    Agreed, making the virtual environment management and so much else disappear lets so much more focus go to python itself.

spagettnet  9 days ago

Of all the great things people say about UV, this is the one that sold me on it when I found this option in the docs. Such a nice feature.