diff --git a/extensions/api.d.ts b/extensions/api.d.ts
index 863519e20..b78b72f41 100644
--- a/extensions/api.d.ts
+++ b/extensions/api.d.ts
@@ -1,4 +1,5 @@
 import type { RequestHandler } from 'express';
+import type helpers from '../src/backend/src/helpers.js';
 
 declare global {
   namespace Express {
@@ -25,10 +26,17 @@ type RouterMethods = {
   };
 }
 
+type CoreRuntimeModule = {
+  util: {
+    helpers: typeof helpers,
+  }
+}
+
 interface Extension extends RouterMethods {
   // import(module: 'core'): {
   //   UserActorType: typeof UserActorType;
   // };
+  import(module: 'core'): CoreRuntimeModule;
   import(module: string): any;
 }
 
diff --git a/extensions/jsconfig.json b/extensions/jsconfig.json
index 0da51fce3..04ce18e6c 100644
--- a/extensions/jsconfig.json
+++ b/extensions/jsconfig.json
@@ -1,7 +1,7 @@
 {
   "compilerOptions": {
     "target": "ES2020",
-    "module": "CommonJS",
+    "module": "esnext",
     "moduleResolution": "node",
     "baseUrl": ".",
     "paths": {
diff --git a/extensions/tsconfig.json b/extensions/tsconfig.json
index 187f89a33..f531272af 100644
--- a/extensions/tsconfig.json
+++ b/extensions/tsconfig.json
@@ -1,9 +1,11 @@
 {
   "compilerOptions": {
     "target": "ES2020",
-    "module": "CommonJS",
+    "allowJs": true,
+    "module": "esnext",
     "moduleResolution": "node",
     "baseUrl": ".",
+    "outDir": "/dev/null",
     "paths": {
       "../src/*": ["../src/*"]
     },