diff --git a/tools/isobuild/import-scanner.js b/tools/isobuild/import-scanner.js
index 917b65edee..323e2eaac5 100644
--- a/tools/isobuild/import-scanner.js
+++ b/tools/isobuild/import-scanner.js
@@ -66,7 +66,9 @@ function stripHashBang(dataString) {
 }
 
 const reifyCompileWithCache = wrap(function ({ dataString }) {
-  return reifyCompile(stripHashBang(dataString)).code;
+  return reifyCompile(stripHashBang(dataString), {
+    dynamicImport: true,
+  }).code;
 }, {
   makeCacheKey({ hash }) {
     return hash;
diff --git a/tools/static-assets/server/runtime.js b/tools/static-assets/server/runtime.js
index 3d521e57d0..7faf43f6e6 100644
--- a/tools/static-assets/server/runtime.js
+++ b/tools/static-assets/server/runtime.js
@@ -18,3 +18,8 @@ Mp.load = function (filename) {
   }
   return result;
 };
+
+const resolved = Promise.resolve();
+Mp.dynamicImport = function (id) {
+  return resolved.then(() => require(id));
+};