diff --git a/system/nix.nix b/system/nix.nix
index 0338ab3..e1de8f3 100644
--- a/system/nix.nix
+++ b/system/nix.nix
@@ -1,4 +1,4 @@
-{ config, pkgs, lib, inputs, ... }:
+{ lib, inputs, ... }:
 
 let flakes = lib.filterAttrs (name: value: value ? outputs) inputs;
 in {
@@ -11,16 +11,9 @@ in {
   nix.settings = {
     trusted-users = [ "@wheel" ];
     auto-optimise-store = true;
-    substituters = [
-      "https://hydra.iohk.io"
-      "https://shajra.cachix.org"
-      "https://felschr.cachix.org"
-    ];
-    trusted-public-keys = [
-      "hydra.iohk.io:f/Ea+s+dFdN+3Y/G+FDgSq+a5NEWhJGzdjvKNGv0/EQ="
-      "shajra.cachix.org-1:V0x7Wjgd/mHGk2KQwzXv8iydfIgLupbnZKLSQt5hh9o="
-      "felschr.cachix.org-1:raomy5XA2tsVkBoG6wo70ARIn+V24IXhWaSe3QZo12A="
-    ];
+    substituters = [ "https://felschr.cachix.org" ];
+    trusted-public-keys =
+      [ "felschr.cachix.org-1:raomy5XA2tsVkBoG6wo70ARIn+V24IXhWaSe3QZo12A=" ];
   };
 
   system.autoUpgrade = {