While investigating I see:


  #12 22.76       /tmp/pip-build-env-lxryl305/overlay/lib/python3.14/
site-packages/setuptools/config/_apply_pyprojecttoml.py:82:
SetuptoolsDeprecationWarning: `project.license` as a TOML table is
deprecated
  #12 22.76       !!
  #12 22.76
  #12 22.76
              
********************************************************************************
  #12 22.76               Please use a simple string containing a SPDX
expression for `project.license`. You can also use `project.license-
files`. (Both options available on setuptools>=77.0.0).
  #12 22.76
  #12 22.76               By 2027-Feb-18, you need to update your
project and remove deprecated calls
  #12 22.76               or your builds will no longer be supported.
  #12 22.76
  #12 22.76               See https://packaging.python.org/en/latest/
guides/writing-pyproject-toml/#license for details.

Since this will require a new release of gpg to make it buildable and it
takes a while
to get releases to pypi, I am flagging it now.

Note: you only see the Deprecation warning during build if the gpg build
fails.

You can force the error using

  RUN PYTHONWARNINGS="error" pip install --no-cache-dir gpg --no-build-
isolation

in the Dockerfile.

Also Roundup requires setuptools >= 78.1.1 so the SPDX license format is
supported in all
recent Roundup builds and Roundup uses that format in setup.py:

          license_expression="MIT AND ZPL-2.0 AND PSF-2.0",