diff --git a/docs/sw.js b/docs/sw.js
index 8b13789..182ebca 100644
--- a/docs/sw.js
+++ b/docs/sw.js
@@ -1 +1,15 @@
-
+const log = (...a) => console.log("[SW]", ...a);
+self.addEventListener("install", (e) => {
+  log("install");
+  self.skipWaiting();
+});
+self.addEventListener("activate", (e) => {
+  log("activate");
+  e.waitUntil(self.clients.claim());
+});
+self.addEventListener("fetch", (e) => {
+  if (e.request.mode === "navigate") log("navigate", e.request.url);
+});
+self.addEventListener("message", (e) => {
+  log("message", e.data);
+});