diff --git a/modules/shell/git.nix b/modules/shell/git.nix
index c3cf983..02b9c7e 100644
--- a/modules/shell/git.nix
+++ b/modules/shell/git.nix
@@ -12,7 +12,9 @@
       lfs.enable = true;
       signing = {
         key = "/home/${user}/.ssh/id_ed25519_sk_rk_yubiC";
-        signByDefault = false;
+        signByDefault = true;
+      extraConfig = {
+        gpg = { format = ssh; };
       };
     };
   };