Added cachix. I'm tired of compiling CUDA

etc/nixos/cachix.nix

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+
+# WARN: this file will get overwritten by $ cachix use <name>
+{ pkgs, lib, ... }:
+
+let
+  folder = ./cachix;
+  toImport = name: value: folder + ("/" + name);
+  filterCaches = key: value: value == "regular" && lib.hasSuffix ".nix" key;
+  imports = lib.mapAttrsToList toImport (lib.filterAttrs filterCaches (builtins.readDir folder));
+in {
+  inherit imports;
+  nix.settings.substituters = ["https://cache.nixos.org/"];
+}

etc/nixos/cachix/niri.nix

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+
+{
+  nix = {
+    settings = {
+      substituters = [
+        "https://niri.cachix.org"
+      ];
+      trusted-public-keys = [
+        "niri.cachix.org-1:Wv0OmO7PsuocRKzfDoJ3mulSl7Z6oezYhGhR+3W2964="
+      ];
+    };
+  };
+}

etc/nixos/cachix/nix-community.nix

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+
+{
+  nix = {
+    settings = {
+      substituters = [
+        "https://nix-community.cachix.org"
+      ];
+      trusted-public-keys = [
+        "nix-community.cachix.org-1:mB9FSh9qf2dCimDSUo8Zy7bkq5CX+/rkCWyvRCYg3Fs="
+      ];
+    };
+  };
+}