Service Workers That Make Your App Load in Under 100ms on Repeat Visits
Service workers are the engine behind every PWA capability: offline access, background sync, push notifications, and instant loading. We implement service workers with caching strategies tailored to each resource type so your app loads near-instantly from cache and works reliably on any network condition.
higher conversion for 1-second sites compared to 5-second sites, and service worker caching makes repeat visits load in under 100ms from local cache
Portent, 2022
Service Worker Implementation
What's Included
Everything you get with our Service Worker Implementation
Caching Strategy Architecture
Per-resource caching strategies: cache-first for static assets and app shell, network-first for API responses, stale-while-revalidate for semi-dynamic content, and cache-only for offline fallbacks
Lifecycle and Update Management
Service worker registration, installation, activation, and update flows with skip-waiting strategies, versioned caches, and user notification when new versions are available
Background Sync and Offline Queue
Background sync API implementation that queues failed network requests and replays them when connectivity returns, with conflict resolution for offline-created data
Our Service Worker Implementation Process
Resource Audit and Strategy Design
We catalog every resource your app requests: HTML pages, CSS bundles, JavaScript chunks, API endpoints, images, and fonts. We assign a caching strategy to each based on freshness requirements and access patterns.
Service Worker Development
We implement the service worker with Workbox or custom code depending on complexity. We configure precaching for critical assets, runtime caching for dynamic resources, and offline fallback pages for uncached routes.
Background Sync and Offline Queue
We implement background sync for offline data submission, conflict resolution for concurrent offline edits, and retry logic for failed requests. We test every offline workflow end-to-end.
Update Strategy and Testing
We configure service worker update flows with cache versioning, skip-waiting options, and user notification for major updates. We test across Chrome, Safari, Firefox, and Edge including iOS Safari's service worker behavior.
Key Benefits
Instant loading from local cache
The app shell and static assets are cached on first visit. Every subsequent visit loads from local storage in under 100ms regardless of network speed. Users on slow 3G connections get the same instant load as users on fiber.
Reliable offline access
Service workers intercept network requests and serve cached responses when the network is unavailable. Users in elevators, airplanes, subways, and rural areas continue using your app. Offline fallback pages handle uncached routes gracefully.
Background sync that never loses data
When users submit forms or create data while offline, the Background Sync API queues the requests. When connectivity returns, the service worker replays queued requests in order. No data is lost, no duplicate submissions occur.
Research & Evidence
Backed by industry research and proven results
Page Load and Conversion
A 1-second site converts at 3x the rate of a 5-second site, and service workers eliminate network latency on repeat visits by serving cached responses
Portent (2022)
PWA Impact Study
Progressive web apps with properly implemented service workers see 68% more mobile traffic and 15x faster load times
Google (2020)
Related Services
Explore more of our progressive web apps services
Offline-First Architecture That Treats the Network as an Enhancement, Not a Requirement
Offline-first architecture that treats the network as an enhancement, not a requirement. Your app works reliably on any connection or no connection.
Web Push Notifications That Bring Users Back Without an App Store Download
Web push notifications that re-engage users even when your app is closed. Higher opt-in rates than native apps because no download is required first.
Progressive Web Apps That Users Install, Use Offline, and Return to Daily
End-to-end progressive web app development with service workers, offline support, and installability. PWAs see 68% more mobile traffic than traditional web.
PWA Performance That Achieves Sub-Second Loading on 3G Connections
PWA performance optimization with service worker caching, code splitting, and lazy loading. Sub-second TTI on 3G with 100ms repeat loads from cache.
Make Your App Load Instantly and Work Offline
Share your application requirements. We will design the service worker strategy that makes your app fast on any connection and functional with no connection at all.
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