modules/ccache.nix

{ username
, config
, ...
}: {
  config = {
    environment.persistence = {
      "/nix/persist".users.${username}.directories = [
        {
          directory = ".cache/ccache";
          mode = "0700";
        }
      ];
      "/large/persist".directories = [ config.programs.ccache.cacheDir ];
    };
    programs.ccache.enable = true;
    /* nixpkgs.config.replaceStdenv = { pkgs }: pkgs.ccacheStdenv; */
    /* nixpkgs.config.allowBroken = true; */
    nix.settings.extra-sandbox-paths = [ config.programs.ccache.cacheDir ];
    nixpkgs.overlays = [
      (self: super: {
        ccacheWrapper = super.ccacheWrapper.override {
          extraConfig = ''
            export CCACHE_COMPRESS=1
            export CCACHE_DIR="${config.programs.ccache.cacheDir}"
            export CCACHE_UMASK=007
            if [ ! -d "$CCACHE_DIR" ]; then
              echo "====="
              echo "Directory '$CCACHE_DIR' does not exist"
              echo "Please create it with:"
              echo "  sudo mkdir -m0770 '$CCACHE_DIR'"
              echo "  sudo chown root:nixbld '$CCACHE_DIR'"
              echo "====="
              exit 1
            fi
            if [ ! -w "$CCACHE_DIR" ]; then
              echo "====="
              echo "Directory '$CCACHE_DIR' is not accessible for user $(whoami)"
              echo "Please verify its access permissions"
              echo "====="
              exit 1
            fi
          '';
        };
      })
    ];
  };
}