Nix Toolchain

Lix vs CppNix

This repo uses Lix (a Nix fork) on most platforms for its improved error messages and performance. The exception is x86_64-darwin (Intel Macs), where Lix dropped support – those machines use the upstream CppNix package instead.

The selection logic lives in modules/common/nix-core.nix:

nix.package =
  if pkgs.stdenv.hostPlatform.system == "x86_64-darwin"
  then pkgs.nix
  else pkgs.lix;

Experimental Features

The flake enables nix-command and flakes experimental features globally. These are required for nix build, nix develop, and flake-based workflows.

Binary Caches

Three substituters are configured to speed up builds:

Garbage Collection

Automatic weekly GC deletes store paths older than 7 days:

nix.gc = {
  automatic = true;
  options = "--delete-older-than 7d";
};

Manual cleanup is available via mise run nix:clean [window] (prune old system generations for this config) and mise run nix:gc (aggressive store-wide garbage collection).