configuration/common: split common into seperate files

configuration/common/nix.nix

@@ -0,0 +1,56 @@
+{ lib, pkgs, ... }:
+
+{
+
+  clerie.nixfiles.enable = true;
+
+  nix.settings = {
+    trusted-users = [ "@wheel" "@guests" ];
+    auto-optimise-store = true;
+    # Keep buildtime dependencies
+    keep-outputs = true;
+    # Build local, when caches are broken
+    fallback = true;
+  };
+
+  nix.gc = lib.mkDefault {
+    automatic = true;
+    dates = "weekly";
+    options = "--delete-older-than 30d";
+  };
+
+
+  nix.settings = {
+    experimental-features = [
+      "flakes"
+      "nix-command"
+      "repl-flake"
+    ];
+    substituters = [
+      "https://nix-cache.clerie.de"
+    ];
+    trusted-public-keys = [
+      "nix-cache.clerie.de:bAt1GJTS9BOTcXFWj3nURrSlcjqikCev9yDvqArMP5g="
+    ];
+  };
+
+  # Pin current nixpkgs channel and flake registry to the nixpkgs version
+  # the host got build with
+  nix.nixPath = lib.mkForce [ "nixpkgs=${lib.cleanSource pkgs.path}" ];
+  nix.registry = lib.mkForce {
+    "nixpkgs" = {
+       from = {
+         type = "indirect";
+         id = "nixpkgs";
+       };
+       to = {
+         type = "path";
+         path = lib.cleanSource pkgs.path;
+       };
+       exact = true;
+    };
+  };
+
+  documentation.doc.enable = false;
+
+}