xdeb namespace/sysroot for Void

[thetredev]

This one might be a huge one to implement, and it might not even be possible at all.

To overcome all of the "package XYZ might break Void when installed via xdeb" could probably maybe fixed or worked around using a completely separate namespace in the sense of what NixOS does: layers/snapshots you can jump around to. We don't need the snapshot and jumping around functionality, just the "the package isn't installed to your actual sysroot" functionality.

That namespace could be located under /usr/local/xdeb, for example. This directory would represent the "virtual sysroot" for xdeb. So we'd end up with the following structure of an arbitrary package package1:

• /usr/local/xdeb/package1/etc/package1/my-config-file.conf
• /usr/local/xdeb/package1/usr/bin/package1

Installing packages to that namespace location might be fairly simple, however the hard part would most likely be to be able to execute installed packages under Void this way. I guess the package1 binary from the example above might not be able to find its config file under the namespace location. A workaround might be to link everything from the actual Void Linux sysroot (/) to the namespace location, like:

• /etc/package1 → /usr/local/xdeb/package1/etc/package1
• /usr/bin/package1 → /usr/local/xdeb/package1/usr/bin/package1

But... while all this might look and sound great, we might end up breaking packages in the process.

Any thoughs?