diff --git a/index.js b/index.js
index 971cfd8..df3021c 100644
--- a/index.js
+++ b/index.js
@@ -117,6 +117,7 @@ export default function serviceWorker(config) {
                     ?? [];
 
                 assets = [...new Set([...assets, ..._routes, ..._pages, ..._pagesWithoutEndSlash])]
+                    .filter(asset => !asset.includes('404'));
                 console.log('>>> assets', assets);
 
                 try {
diff --git a/src/pages/404.astro b/src/pages/404.astro
new file mode 100644
index 0000000..6520cc2
--- /dev/null
+++ b/src/pages/404.astro
@@ -0,0 +1,3 @@
+---
+---
+404
\ No newline at end of file