I'd recommend re-creating the virtual environment inside the Docker container.

The problem is you are mounting a virtual environment you have built in your development environment into a Docker container. Inside your virtual environment there's a `python` binary that in reality is a symlink to the python binary in your OS:

  cd .venv
  ls -l bin/python
  lrwxr-xr-x@ 1 myuser  staff  85 Oct 29 13:13 bin/python -> /Users/myuser/.local/share/uv/python/cpython-3.13.5-macos-aarch64-none/bin/python3.13

So, when you mount that virtual environment in a container, it won't find the path to the python binary.

The most basic fix would be recreating the virtual environment inside the container, so from your project (approximately, I don't know the structure):

   docker run -it --rm -v$(pwd):/app --entrypoint ash ghcr.io/astral-sh/uv:python3.12-alpine
  / # cd /app
  /app # uv pip install --system -r requirements.txt
  Using Python 3.12.12 environment at: /usr/local
  Resolved 23 packages in 97ms
  Prepared 23 packages in 975ms
  Installed 23 packages in 7ms
  [...]
  /app # python
  Python 3.12.12 (main, Oct  9 2025, 22:34:22) [GCC 14.2.0] on linux
  Type "help", "copyright", "credits" or "license" for more information.

But, if you're developing and don't wanna build the virtual environment each time you start the container, you could create a cache volume for uv, and after the first time installation, everything is going to be way faster:

  # First run
   docker run -ti --rm --volume .:/app --volume uvcache:/uvcache -e UV_CACHE_DIR="/uvcache" -e UV_LINK_MODE="copy" --entrypoint ash ghcr.io/astral-sh/uv:python3.12-alpine
  / # cd /app
  /app # uv pip install -r requirements.txt --system
  Using Python 3.12.12 environment at: /usr/local
  Resolved 23 packages in 103ms
  Prepared 23 packages in 968ms
  Installed 23 packages in 16ms
  [...]
  # Second run
   docker run -ti --rm --volume .:/app --volume uvcache:/uvcache -e UV_CACHE_DIR="/uvcache" -e UV_LINK_MODE="copy" --entrypoint ash ghcr.io/astral-sh/uv:python3.12-alpine
  / # cd /app
  /app # uv pip install -r requirements.txt --system
  Using Python 3.12.12 environment at: /usr/local
  Resolved 23 packages in 10ms
  Installed 23 packages in 21ms

You can also see some other examples, including a Docker Compose one that automatically updates your packages, here:

https://docs.astral.sh/uv/guides/integration/docker/#develop...

---

Edit notes:

  - UV_LINK_MODE="copy" is to avoid a warning when using the cache volume
  - Creating the venv with `--copies` and mounting it into the container would fail 
    if your host OS is not exactly the same as the containers, and also defeats in a 
    way the use of a versioned Python container