diff --git a/.esbuild/server.ts b/.esbuild/server.ts
index 2a6c826c2..aa7baeda0 100644
--- a/.esbuild/server.ts
+++ b/.esbuild/server.ts
@@ -12,8 +12,12 @@ async function createServer() {
   const externalCtx = await context(
     getBuildConfig({ minify: false, core: false, entryName: 'mermaid-example-diagram' })
   );
-  // TODO: zenuml
   externalCtx.watch();
+  const zenuml = await context(
+    getBuildConfig({ minify: false, core: false, entryName: 'mermaid-zenuml' })
+  );
+  // TODO: zenuml
+  zenuml.watch();
   app.use(cors());
   app.use(express.static('./packages/mermaid/dist'));
   app.use(express.static('./packages/mermaid-zenuml/dist'));
diff --git a/.esbuild/util.ts b/.esbuild/util.ts
index 78d1fbc91..8623a881e 100644
--- a/.esbuild/util.ts
+++ b/.esbuild/util.ts
@@ -20,6 +20,11 @@ export const packageOptions = {
     packageName: 'mermaid-example-diagram',
     file: 'detector.ts',
   },
+  'mermaid-zenuml': {
+    name: 'mermaid-zenuml',
+    packageName: 'mermaid-zenuml',
+    file: 'detector.ts',
+  },
 };
 
 interface MermaidBuildOptions {