diff --git a/nixos/common.nix b/nixos/common.nix
index ccb7917..9fb7c38 100644
--- a/nixos/common.nix
+++ b/nixos/common.nix
@@ -187,9 +187,6 @@
           "adbusers"
           "video"
         ];
-        openssh.authorizedKeys.keys = [
-          "ssh-rsa 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 cardno:000611073199"
-        ];
         initialHashedPassword =
           "$6$tzMk5I1KZlx7byaO$BvlSz7Cgo1g09e4RpxAjrZEuCptzjibF8nDWDfnOImTbz61Py/qzATDAa7HwAC3JyiZxb.2slTb.vA.f25ypd1";
       };
@@ -217,6 +214,25 @@
     enable = true;
     passwordAuthentication = false;
     permitRootLogin = "no";
+
+    hostKeys = [{
+      path = "/etc/ssh/ssh_host_ed25519_key";
+      type = "ed25519";
+    }];
+
+    knownHosts = {
+      "*.monotremata.xyz,10.*,narwhal,caladan,fugu,snitch,trantor,capibara,axolotl,echidna" =
+        {
+          certAuthority = true;
+          publicKey =
+            "ssh-ed25519 AAAAC3NzaC1lZDI1NTE5AAAAIHperHwojXZeo3QWAu1f3kiCKeaHHSqBXJM6ZZEefxdd host_ca";
+        };
+    };
+
+    extraConfig = ''
+      HostCertificate /etc/ssh/ssh_host_ed25519_key-cert.pub
+      TrustedUserCAKeys /etc/ssh/user_ca.pub
+    '';
   };
 
   virtualisation = {