Yeah, I was thinking nix will be probably one of the first things that can easily adapt Fil-C as it already packages in a way that allows different packages to be completely independent of each other, thus Fil-C's ABI compatibility does not matter. I assume other targets will be mostly enterprise distros where the perf hit and source compatibility issues are less of a concern, and memory safety is absolutely critical.

Fil-C compiled flatpaks might be a interesting target as well for normal desktop users. (e.g. running a browser)

I wonder if GPU graphics are possible in Fil-C land? Perhaps only if whole mesa stack is compiled using Fil-C as well, limiting GPU use to open drivers?

That is super cool, and I will probably start running it on at least a test box shortly.

How does python work? Of course I can just add filc.python to my system, but if I `python3 -m pip install whatever` will it just rebuild any C modules with the fil-c compiler?

Right now Python simply does not work at all. I was trying last night just to get the compiler to build, but ran into some Fil-C panics at the last moment when it tries to "freeze" some modules? But it should work.

My idea is to move towards defining Fil-C as a "platform", meaning it would have its own ABI value, so it would look like a target called "x86_64-unknown-linux-filc", and then the magic of Nixpkgs is that it can instantiate a full realm called "pkgsCross.filc" which automatically has every package, whose packages are built on your ordinary non-FilC platform as a cross compilation.

When that works—I hope it works, I probably need help to get it working—you should be able to use all the Nixpkgs packaging helpers like

    pkgs.mkShell {
      packages = [
        (pkgsCross.filc.python3.withPackages (pypkgs: with pypkgs; [
          pandas
          requests
        ]))
      ];
    }

This is already how Nixpkgs can have a pkgsCross.musl that builds everything with Musl as a cross compilation. So it seems reasonable and possible. It should be of wide interest for Nix users, since it would suddenly allow memory safety for whole swaths of the C/C++ packages, it would let NixOS use memory safe builds for core services like OpenSSHd, and so on...

I should probably try to gather some interest among people who are truly familiar with Nixpkgs cross compilation...

Yes filc as abi makes most sense. Do note that while fil-c seems to have pretty good source compatibility some stuff still require patches (like python!)

I don't know how it's going on the nixpkgs side, but my impression from Alpine is that it's pretty normal to carry some patches for any ABI/platform that isn't GNU.

Yep, you can look around in Nixpkgs and see a bunch of conditionally applied patches based on target platform.

My Fil-C flake already includes like 50 different patches extracted from the upstream port catalogue!

That's very exciting! Thank you!