diff --git a/frontend/src/lib/extensions/workers/extensionHost.ts b/frontend/src/lib/extensions/workers/extensionHost.ts
index def1398..0955050 100644
--- a/frontend/src/lib/extensions/workers/extensionHost.ts
+++ b/frontend/src/lib/extensions/workers/extensionHost.ts
@@ -65,20 +65,27 @@ onmessage = async (ev: MessageEvent<ExtensionHostCommand>) => {
       );
       await kv.wait();
 
-      // Transpile TS into JS
-      const out = ts.transpileModule(cmd.source, {
-        compilerOptions: { module: ts.ModuleKind.CommonJS },
-      });
+      try {
+        // Transpile TS into JS
+        const out = ts.transpileModule(cmd.source, {
+          compilerOptions: { module: ts.ModuleKind.ES2022 },
+        });
 
-      // Replace console.* methods with something that logs to UI
-      console.log = log('info');
-      console.info = log('info');
-      console.warn = log('warn');
-      console.error = log('error');
+        // Replace console.* methods with something that logs to UI
+        console.log = log('info');
+        console.info = log('info');
+        console.warn = log('warn');
+        console.error = log('error');
 
-      // eslint-disable-next-line @typescript-eslint/no-unsafe-assignment
-      extFn = ExtensionFunction.constructor('kv', out.outputText);
-      setStatus(ExtensionStatus.Ready);
+        // eslint-disable-next-line @typescript-eslint/no-unsafe-assignment
+        extFn = ExtensionFunction.constructor('kv', out.outputText);
+        setStatus(ExtensionStatus.Ready);
+      } catch (error: unknown) {
+        sendMessage({
+          kind: 'error',
+          error,
+        });
+      }
 
       start();
       break;
diff --git a/frontend/src/ui/pages/Extensions.tsx b/frontend/src/ui/pages/Extensions.tsx
index 9bec3fc..c3d2bb8 100644
--- a/frontend/src/ui/pages/Extensions.tsx
+++ b/frontend/src/ui/pages/Extensions.tsx
@@ -354,7 +354,7 @@ const setupLibrary = (monaco: Monaco, source: string, url: string) => {
     return;
   }
 
-  monaco.languages.typescript.javascriptDefaults.addExtraLib(source, url);
+  monaco.languages.typescript.typescriptDefaults.addExtraLib(source, url);
   monaco.editor.createModel(source, 'typescript', monaco.Uri.parse(url));
 };
 
@@ -368,13 +368,15 @@ function ExtensionEditor() {
 
   useEffect(() => {
     if (monaco) {
-      monaco.languages.typescript.javascriptDefaults.setEagerModelSync(true);
-      monaco.languages.typescript.javascriptDefaults.setDiagnosticsOptions({
+      monaco.languages.typescript.typescriptDefaults.setEagerModelSync(true);
+      monaco.languages.typescript.typescriptDefaults.setDiagnosticsOptions({
         noSemanticValidation: false,
         noSyntaxValidation: false,
+        diagnosticCodesToIgnore: [1375, 2792],
       });
-      monaco.languages.typescript.javascriptDefaults.setCompilerOptions({
+      monaco.languages.typescript.typescriptDefaults.setCompilerOptions({
         target: monaco.languages.typescript.ScriptTarget.ES2020,
+        module: monaco.languages.typescript.ModuleKind.ESNext,
         allowNonTsExtensions: true,
       });
       setupLibrary(monaco, kilovoltDefinition, 'ts:index.d.ts');