diff --git a/cypress/integration/rendering/zenuml.spec.js b/cypress/integration/rendering/zenuml.spec.js
new file mode 100644
index 000000000..f317fbe82
--- /dev/null
+++ b/cypress/integration/rendering/zenuml.spec.js
@@ -0,0 +1,19 @@
+import { imgSnapshotTest } from '../../helpers/util.js';
+
+describe('Zen UML', () => {
+  it('Basic Zen UML diagram', () => {
+    imgSnapshotTest(
+      `
+    zenuml
+			A.method() {
+        if(x) {
+          B.method() {
+            selfCall() { return X }
+          }
+        }
+      }
+    `,
+      {}
+    );
+  });
+});
diff --git a/cypress/platform/viewer.js b/cypress/platform/viewer.js
index a99c150f1..0b566e329 100644
--- a/cypress/platform/viewer.js
+++ b/cypress/platform/viewer.js
@@ -1,5 +1,6 @@
 import mermaid2 from './mermaid.esm.mjs';
 import externalExample from '../../packages/mermaid-example-diagram/dist/mermaid-example-diagram.core.mjs';
+import zenUml from '../../packages/mermaid-zenuml/dist/mermaid-zenuml.core.mjs';
 
 function b64ToUtf8(str) {
   return decodeURIComponent(escape(window.atob(str)));
@@ -44,7 +45,7 @@ const contentLoaded = async function () {
       document.getElementsByTagName('body')[0].appendChild(div);
     }
 
-    await mermaid2.registerExternalDiagrams([externalExample]);
+    await mermaid2.registerExternalDiagrams([externalExample, zenUml]);
     mermaid2.initialize(graphObj.mermaid);
     await mermaid2.run();
   }