diff --git a/modules/nixos/programs/git/default.nix b/modules/nixos/programs/git/default.nix
index 65371382..2c703a64 100644
--- a/modules/nixos/programs/git/default.nix
+++ b/modules/nixos/programs/git/default.nix
@@ -15,7 +15,11 @@ in
     enable = mkEnableOption "git version control";
     userName = mkOpt str user.accounts.fullName "The name to configure git with";
     userEmail = mkOpt str user.accounts.primaryEmailAddress "The email to configure git with";
-    signingKey = mkOpt (nullOr str) "1E9AFDF3275F99EE" "The key ID to sign commits with";
+    signingKey = mkOption {
+      description = "The key ID to sign commits with";
+      type = nullOr str;
+      default = null;
+    };
     signByDefault = mkOpt bool true "Whether to sign Git commits using GPG";
     githubUsername = mkOpt str "gekoke" "The GitHub username to use";
   };
diff --git a/systems/x86_64-linux/carbon/default.nix b/systems/x86_64-linux/carbon/default.nix
index 72c0a8bf..23666267 100644
--- a/systems/x86_64-linux/carbon/default.nix
+++ b/systems/x86_64-linux/carbon/default.nix
@@ -16,6 +16,7 @@
     hardware.nvidia.enable = true;
     roles.workstation.enable = true;
     secrets.enable = true;
+    programs.git.signingKey = "1E9AFDF3275F99EE";
   };
 
   home-manager.users.geko = {
diff --git a/systems/x86_64-linux/silicon/default.nix b/systems/x86_64-linux/silicon/default.nix
index c90d1670..344417c6 100644
--- a/systems/x86_64-linux/silicon/default.nix
+++ b/systems/x86_64-linux/silicon/default.nix
@@ -70,7 +70,6 @@ in
     programs = {
       git = enabled // {
         userEmail = "gregor.grigorjan@gamesglobal.com";
-        signingKey = "FB5F09CB29F94BC5";
       };
       ssh = enabled;
       emacs = enabled // {