diff --git a/server/handlers/generate-service-worker.js b/server/handlers/generate-service-worker.js
index 1cc31ec7..415872d4 100644
--- a/server/handlers/generate-service-worker.js
+++ b/server/handlers/generate-service-worker.js
@@ -13,6 +13,7 @@ async function generateServiceWorker(
   }
 ) {
   const configVersion = await maxConfigVersion(config, domainSlug);
+  const customAssetHelper = typeof assetHelper === 'function' && Object.keys(config).length > 0 ? assetHelper(config) : assetHelper;
 
   return new Promise((resolve) => {
     renderServiceWorker(
@@ -20,12 +21,12 @@ async function generateServiceWorker(
       "js/service-worker",
       {
         config,
-        serviceWorkerHelper: assetHelper.serviceWorkerContents(),
-        assetPath: assetHelper.assetPath,
+        serviceWorkerHelper: customAssetHelper.serviceWorkerContents(),
+        assetPath: customAssetHelper.assetPath,
         hostname: req.hostname,
-        assetHash: assetHelper.assetHash,
+        assetHash: customAssetHelper.assetHash,
         configVersion,
-        getFilesForChunks: assetHelper.getFilesForChunks,
+        getFilesForChunks: customAssetHelper.getFilesForChunks,
         routes: generateRoutes(config, domainSlug).filter(
           (route) => !route.skipPWA
         ),
diff --git a/server/handlers/isomorphic-handler.js b/server/handlers/isomorphic-handler.js
index 30dd3217..88e597a2 100644
--- a/server/handlers/isomorphic-handler.js
+++ b/server/handlers/isomorphic-handler.js
@@ -126,7 +126,8 @@ exports.handleIsomorphicShell = async function handleIsomorphicShell(
   }
 ) {
   const url = urlLib.parse(req.url, true);
-  const freshRevision = `${assetHelper.assetHash("app.js")}-${await maxConfigVersion(config, domainSlug)}`;
+  const customAssetHelper = typeof assetHelper === 'function' && Object.keys(config).length > 0 ? assetHelper(config) : assetHelper;
+  const freshRevision = `${customAssetHelper.assetHash("app.js")}-${await maxConfigVersion(config, domainSlug)}`;
 
   if (req.query.revision && req.query.revision !== freshRevision)
     return res.status(503).send("Requested Shell Is Not Current");
@@ -144,7 +145,7 @@ exports.handleIsomorphicShell = async function handleIsomorphicShell(
     res.setHeader("Vary", "Accept-Encoding");
 
     if (preloadJs) {
-      res.append("Link", `<${assetHelper.assetPath("app.js")}>; rel=preload; as=script;`);
+      res.append("Link", `<${customAssetHelper.assetPath("app.js")}>; rel=preload; as=script;`);
     }
     const seoInstance = getSeoInstance(seo, config, "shell");
     const seoTags = seoInstance && seoInstance.getMetaTags(config, "shell", result, { url });
@@ -430,6 +431,7 @@ exports.handleIsomorphicRoute = function handleIsomorphicRoute(
   }
 ) {
   const url = urlLib.parse(req.url, true);
+  const customAssetHelper = typeof assetHelper === 'function' && Object.keys(config).length > 0 ? assetHelper(config) : assetHelper;
 
   function writeResponse(result) {
     const statusCode = result.httpStatusCode || 200;
@@ -473,7 +475,7 @@ exports.handleIsomorphicRoute = function handleIsomorphicRoute(
     });
 
     if (preloadJs) {
-      res.append("Link", `<${assetHelper.assetPath("app.js")}>; rel=preload; as=script;`);
+      res.append("Link", `<${customAssetHelper.assetPath("app.js")}>; rel=preload; as=script;`);
     }
     const oneSignalScript = oneSignalServiceWorkers ? getOneSignalScript({ config, publisherConfig }) : null;
     return pickComponent.preloadComponent(store.getState().qt.pageType, store.getState().qt.subPageType).then(() =>