Making a Writing App Work Offline: Service Workers and Cache Strategies

Writers write everywhere — coffee shops with flaky wifi, airplanes, parks. A writing app that requires an internet connection is failing its users. Here's how I made TaleForge work offline. The Requirements The editor must work without internet Changes must sync when connectivity returns No data loss — ever The user shouldn't have to think about any of this Service Worker Strategy I use a cache-first strategy for static assets (JS, CSS, images) and a network-first strategy for API calls. // service-worker.js (simplified) self.addEventListener('fetch', (event) => { const url = new URL(event.request.url); if (url.pathname.startsWith('/api/')) { // Network first for API calls event.respondWith( fetch(event.request) .catch(() => caches.match(event.request)) ); } else { // Cache first for static assets event.respondWith( caches.match(event.request) .then(cached => cached || fetch(event.request)) ); } }); The Sync Problem When a writer is offline and making edits, those changes need