I'm tempted to launch into a diatribe about namespacing, containers, and application isolation generally, but before I do - why is it that you /want/ to use the system Python environment? Had you just not considered the option of virtual environments? Awesome though it is, virtualenv can be very tedious if you need to install hundreds of megabytes of compiler and -devel packages. System packages are attractive precisely because you can avoid this.
That’s why you should use a build server and not ship build environments.
I've had to do all sorts of tedious things with containers where I spin up a temporary container to build a bunch of .whl files, then actually install them in the final container - all to avoid bloating the container image with the build tools.
I don’t see how that’s tedious since a compute does that for me. Although I don’t see any value at wheeling them (and some packages cannot be wheeled); my CI builds a venv and puts it into a container. There’s nothing tedious about it at all.
It's a real shame that binary wheels on Linux/PyPI aren't a thing.
This is incorrect.