Concepts
Foundational knowledge for building offline-first web apps.
Concepts
Before diving into the patterns, understand the foundations that make offline-first apps possible.
Offline Capability & Service Workers
What offline means beyond caching. How service workers enable it. The versioning problem and Swoff's versioned SW solution.
PWA & Browser APIs
PWA is just three small additions. The browser APIs that power offline apps — Cache API, IndexedDB, Fetch — and their browser support.
iOS Safari Limitations
Critical platform constraints: 7-day eviction, 50 MB storage limit, no beforeinstallprompt, aggressive SW lifecycle, and workarounds.
SEO & Offline-First
How crawlers handle Service Workers, hybrid SSR + Swoff approaches, and when to use what.
Swoff