The Mobile-First PWA Challenge
Build offline-capable progressive web apps with service workers, app-like navigation, and push notifications.
Build your unique app
Same PWA patterns. Your unique, hilarious mobile experience.
The 10-day journey
Each day, a stakeholder email drops with new requirements. Just like real work.
Responsive design, touch targets, and flexible layouts.
App icons, theme colors, and home screen installation.
Registration, lifecycle events, and basic caching.
Network-first, cache-first, stale-while-revalidate patterns.
IndexedDB for structured data storage and sync tracking.
Connection indicators, pending changes, and sync status.
Sync data when app is closed. New batch sync API endpoint.
Permission prompts, notification display, and click handling.
Code splitting, lazy loading, and bundle optimization.
App-like navigation, gestures, and production deploy.
What you'll actually learn
Not just how to build a PWA — but how to build one that doesn't fall apart at scale.
Service Workers
Cache strategies, background sync, lifecycle management, and update handling.
Offline Data
IndexedDB storage, sync status tracking, queue management, and local-first architecture.
Push Notifications
Permission UX, notification display, click handling, and settings management.
Performance
Code splitting, lazy loading, bundle optimization, and Lighthouse scores.
Ready to build your unique app?
Learn the architecture patterns that power Twitter and Instagram.
Other challenges
View allCheck out our other challenges to continue building your skills.