In Fromager 0.31 and earlier, we assume that packages are built for the same Python version and interpreter as Fromager's Python. For example if Fromager is installed in a Python 3.11 virtual env, then all packages are built for Python 3.11.

Fromager should be able to build a package for another Python interpreter, e.g.

fromager --python-interpreter=/usr/bin/python3.12 ...

I think all it takes is to replace sys.executable with a command line parameter and get platform.python_version() from that interpreter. Then Fromager will create virtual envs for a different Python version.