diff --git a/nixos/tests/step-ca.nix b/nixos/tests/step-ca.nix
index a855b590232d..31ec0078e0f6 100644
--- a/nixos/tests/step-ca.nix
+++ b/nixos/tests/step-ca.nix
@@ -62,6 +62,24 @@ import ./make-test-python.nix ({ pkgs, ... }:
             };
           };
 
+        caclientcaddy =
+          { config, pkgs, ... }: {
+            security.pki.certificateFiles = [ "${test-certificates}/root_ca.crt" ];
+
+            networking.firewall.allowedTCPPorts = [ 80 443 ];
+
+            services.caddy = {
+              enable = true;
+              virtualHosts."caclientcaddy".extraConfig = ''
+                respond "Welcome to Caddy!"
+
+                tls caddy@example.org {
+                  ca https://caserver:8443/acme/acme/directory
+                }
+              '';
+            };
+          };
+
         catester = { config, pkgs, ... }: {
           security.pki.certificateFiles = [ "${test-certificates}/root_ca.crt" ];
         };
@@ -73,5 +91,8 @@ import ./make-test-python.nix ({ pkgs, ... }:
         caserver.wait_for_unit("step-ca.service")
         caclient.wait_for_unit("acme-finished-caclient.target")
         catester.succeed("curl https://caclient/ | grep \"Welcome to nginx!\"")
+
+        caclientcaddy.wait_for_unit("caddy.service")
+        catester.succeed("curl https://caclientcaddy/ | grep \"Welcome to Caddy!\"")
       '';
   })