ccache

base.nix

@@ -7,6 +7,7 @@
     ./cachix.nix # update with `cachix use --mode nixos -d . FOOBAR`
     ./secrets
     ./profiles/locale-no.nix
+    ./profiles/ccache.nix
     ./profiles/upgrade-diff.nix
     ./profiles/lix.nix
     ./profiles/mounts/common-nfs.nix

profiles/ccache.nix

@@ -0,0 +1,47 @@
+{
+  config,
+  pkgs,
+  lib,
+  ...
+}:
+
+# TODO: sccache
+
+{
+  programs.ccache.enable = true;
+  programs.ccache.owner = "root"; # default
+  programs.ccache.group = "nixbld"; # default
+
+  programs.nix-required-mounts.enable = true;
+  programs.nix-required-mounts.allowedPatterns."ccache" = {
+    onFeatures = [
+      "ccache"
+      # "sccache"
+    ];
+    paths = [
+      config.programs.ccache.cacheDir
+      # "/var/cache/sccache"
+    ];
+  };
+
+  nix.settings.system-features = [
+    "ccache"
+    # "sccache"
+  ];
+  systemd.tmpfiles.settings."50-ccache" =
+    let
+      tmp = rec {
+        "d" = {
+          user = config.programs.ccache.owner;
+          group = config.programs.ccache.group;
+          mode = "0770";
+        };
+        "Z" = d;
+      };
+    in
+    {
+      "/var/cache/ccache" = tmp;
+      # "/var/cache/sccache" = tmp;
+    };
+
+}