diff --git a/nix/os/devices/srv0.home-ch.stefanjunker.de/versions.nix b/nix/os/devices/srv0.home-ch.stefanjunker.de/versions.nix
index a9883cf..addf3ae 100644
--- a/nix/os/devices/srv0.home-ch.stefanjunker.de/versions.nix
+++ b/nix/os/devices/srv0.home-ch.stefanjunker.de/versions.nix
@@ -2,41 +2,21 @@ let
   nixpkgs = {
     url = "https://github.com/NixOS/nixpkgs/";
     ref = "nixos-21.11";
-    rev = "e34c5379866833f41e2a36f309912fa675d687c7";
+    rev = "0f316e4d72daed659233817ffe52bf08e081b5de";
   };
 in
 
 {
   inherit nixpkgs;
   "channels-nixos-stable" = nixpkgs;
-  "channels-nixos-21.05" = {
-    url = "https://github.com/NixOS/nixpkgs/";
-    ref = "nixos-21.05";
-    rev = "b86b6bc5e753919ab4d7c902210234f324d0efa4";
-  };
-  "channels-nixos-20.03" = {
-    url = "https://github.com/NixOS/nixpkgs/";
-    ref = "nixos-20.03";
-    rev = "1db42b7fe3878f3f5f7a4f2dc210772fd080e205";
-  };
-  "channels-nixos-19.09" = {
-    url = "https://github.com/NixOS/nixpkgs/";
-    ref = "nixos-19.09";
-    rev = "75f4ba05c63be3f147bcc2f7bd4ba1f029cedcb1";
-  };
-  "channels-nixos-unstable" = {
-    url = "https://github.com/NixOS/nixpkgs/";
-    ref = "nixos-unstable";
-    rev = "c71f061c68ba8ce53471b767d5049cbd0f3d8490";
-  };
   "nixpkgs-master" = {
     url = "https://github.com/NixOS/nixpkgs/";
     ref = "master";
-    rev = "75ef7d62b0ca2253d72f4dccefe71660c30ba6b4";
+    rev = "4269133f096f6da2fa2858697afbe2a4ac94a983";
   };
   "home-manager-module" = {
     url = "https://github.com/nix-community/home-manager";
     ref = "release-21.11";
-    rev = "6ce1d64073f48b9bc9425218803b1b607454c1e7";
+    rev = "28b9ae40c45c5e7711c353fee1b7af734e293979";
   };
 }