Add config

1 files changed, 49 insertions, 0 deletions

diff --git a/modules/nix/default.nix b/modules/nix/default.nix
new file mode 100644
index 000000000000..eb2f41c49697
--- /dev/null
+++ b/modules/nix/default.nix
@@ -0,0 +1,49 @@
+{ config, pkgs, options, lib, ... }:
+
+let
+  # Most of the standard Darwin-detection methods cause infinite recursion.
+  isDarwin = options.environment ? "darwinConfig";
+
+  # Copy entire nixlib tree to the store.
+  root =
+    let
+      # Just needed for runCommand and git.
+      bootstrapPkgs = import ../.. {};
+
+      # Remove .git before adding to the store, because it's likely to
+      # be large. Ideally, we would also remove files in .gitignore
+      # here too, but that would require either a builtin for running a
+      # shell command, or a gitignore parser written in Nix (eww).
+      workingTree = builtins.filterSource (path: type: baseNameOf path != ".git") ../..;
+    in
+      # Now, use a derivation to delete any gitignored files. Then, we
+      # can use the resulting Nix store path as root tree.
+      toString (bootstrapPkgs.runCommand "nixlib-root" {} ''
+        cp -R ${workingTree} "$out"
+        chmod -R u+w "$out"
+        ${bootstrapPkgs.git}/bin/git init "$out"
+        ${bootstrapPkgs.git}/bin/git -C "$out" clean -fX
+        rm -rf "$out/.git"
+      '');
+
+in {
+  nix.nixPath = [
+    "nixos-config=${root}/sys/${config.networking.hostName}.nix"
+    root
+  ];
+
+  nixpkgs.overlays =
+    let
+      inherit (builtins) attrNames readDir;
+      dir = ../../nixpkgs-overlays;
+      names = attrNames (readDir dir);
+    in
+      map (o: import "${root}/nixpkgs-overlays/${o}") names;
+
+  services = lib.optionalAttrs isDarwin
+    { nix-daemon.enable = true; };
+
+  nix.package = pkgs.nixUnstable;
+
+  nix.daemonNiceLevel = 2;
+}