diff --git a/src/service-worker.ts b/src/service-worker.ts
index a7e1bd52..15c15fc2 100644
--- a/src/service-worker.ts
+++ b/src/service-worker.ts
@@ -2,19 +2,19 @@ import { register } from 'register-service-worker';
 
 register('/service-worker.js', {
   registrationOptions: { scope: './' },
-  ready(registration) {
+  ready(_registration) {
     console.log('Service worker is active.');
   },
-  registered(registration) {
+  registered(_registration) {
     console.log('Service worker has been registered.');
   },
-  cached(registration) {
+  cached(_registration) {
     console.log('Content has been cached for offline use.');
   },
-  updatefound(registration) {
+  updatefound(_registration) {
     console.log('New content is downloading.');
   },
-  updated(registration) {
+  updated(_registration) {
     console.log('New content is available; please refresh.');
   },
   offline() {