1 files changed, 10 insertions, 4 deletions
diff --git a/lass/1systems/blue/source.nix b/lass/1systems/blue/source.nix
index a32c3a829..a52771a4d 100644
--- a/lass/1systems/blue/source.nix
+++ b/lass/1systems/blue/source.nix
@@ -1,13 +1,19 @@
 { lib, pkgs, ... }:
 {
   nixpkgs = lib.mkForce {
-    derivation = ''
-      with import <nixpkgs> {};
+    derivation = let
+      rev = (lib.importJSON ../../../krebs/nixpkgs.json).rev;
+      sha256 = (lib.importJSON ../../../krebs/nixpkgs.json).sha256;
+    in ''
+      with import (builtins.fetchTarball {
+        url = "https://github.com/nixos/nixpkgs/archive/${rev}.tar.gz";
+        sha256 = "${sha256}";
+      }) {};
       pkgs.fetchFromGitHub {
         owner = "nixos";
         repo = "nixpkgs";
-        rev = "${(lib.importJSON ../../../krebs/nixpkgs.json).rev}";
-        sha256 = "${(lib.importJSON ../../../krebs/nixpkgs.json).sha256}";
+        rev = "${rev}";
+        sha256 = "${sha256}";
       }
     '';
   };