Create isolated event listeners

deno_server.ts

@@ -72,12 +72,21 @@ async function handler(req: Request): Promise<Response> {
     } = body;
 
     const executionPromise = new Promise((resolve, reject) => {
-      availableWorker.worker.onmessage = (e) => {
+      const messageHandler = (e) => {
         resolve(e.data);
+        cleanup();
       };
-      availableWorker.worker.onerror = (e) => {
+      const errorHandler = (e) => {
         reject(new Error(`Worker error: ${e.message}`));
+        cleanup();
       };
+      const cleanup = () => {
+        availableWorker.worker.removeEventListener("message", messageHandler);
+        availableWorker.worker.removeEventListener("error", errorHandler);
+      };
+
+      availableWorker.worker.addEventListener("message", messageHandler);
+      availableWorker.worker.addEventListener("error", errorHandler);
     });
 
     const timeoutPromise = new Promise((_, reject) =>