diff --git a/kat/default.nix b/kat/default.nix
index 8424afc..6c51717 100644
--- a/kat/default.nix
+++ b/kat/default.nix
@@ -65,16 +65,21 @@ in
       };
       systemd.network.enable = true;
 
-      nixpkgs.overlays = map import self-meta.overlay-paths;
+      nixpkgs.overlays = import self-meta.nixpkgs-paths.overlays;
       nix = {
         nixPath = [
           "nixpkgs=${self-meta.nixpkgs-paths.nixpkgs}"
           "nixos=${self-meta.nixpkgs-paths.nixpkgs}"
+          "nixpkgs-src=${self-meta.nixpkgs-paths.nixpkgs-src}"
+          "overlays=${self-meta.nixpkgs-paths.overlays}"
         ];
         channel.enable = false;
         settings = {
           nix-path = config.nix.nixPath;
-          experimental-features = [ "pipe-operator" ];
+          experimental-features = [
+            "pipe-operator"
+            "nix-command"
+          ];
         };
         package = pkgs.lix;
       };
diff --git a/kat/meta.nix b/kat/meta.nix
index d881791..12568f7 100644
--- a/kat/meta.nix
+++ b/kat/meta.nix
@@ -101,11 +101,14 @@ let
           nixpkgs = pkgs.writeText "nixpkgs-entry.nix" ''
             { overlays ? [ ], ... }@args:
             import ${nixpkgs-paths.nixpkgs-src} (args // {
-              overlays = [
-                ${concatStringsSep "\n    " (map (p: "(import ${p})") overlay-paths)}
-              ] ++ overlays;
+              overlays = import ${nixpkgs-paths.overlays} ++ overlays;
             })
           '';
+          overlays = pkgs.writeText "nixpkgs-overlays.nix" ''
+            [
+              ${concatStringsSep "\n  " (map (p: "(import ${p})") overlay-paths)}
+            ]
+          '';
         };
         home-manager = "${sources."home-manager-${version}"}/nixos";
         nixvim = import sources."nixvim-${version}";