> I don’t want a thing that hijacks my terminal and PATH
The shame is ... it never had to be that way. A venv is just a directory with a pyvenv.cfg, symlinks to an interpreter in bin, and a site-packages directory in lib. Running anything with venv/bin/python _is_ running in the virtual environment. Pip operations in the venv are just venv/bin/python -m pip ... . All the source/deactivate/shell nonsense obfuscating that reality did a disservice to a generation of python programmers.