Shiny Data Sync

Reliable, background-capable bidirectional JSON sync between a mobile/desktop app and an HTTP backend. Mirrors the platform-tier guarantees of Shiny.Net.Http (NSURLSession on Apple, Foreground Service on Android, HttpClient fallback elsewhere), but for structured records rather than files.

Provides an outbox for queued local changes (Create/Update/Delete with JSON payloads), an inbox for delta pulls from the server, retry with exponential backoff, pluggable conflict resolution, per-endpoint batching, and AOT-compatible JSON via JsonTypeInfo.

When to Use This Skill

Use this skill when the user needs to:

• Sync app entities to a REST backend reliably, even when offline or backgrounded
• Build an offline-first feature that eventually consistent-syncs to the server
• Queue Create/Update/Delete operations that must survive app kill / device reboot
• Pull server-side changes on a schedule (delta sync)
• Resolve sync conflicts (HTTP 409 / 412) with custom merge logic
• Batch multiple queued operations into a single server round-trip
• Persist a per-endpoint cursor for delta pulls

Do not use this skill for: large file uploads/downloads (use shiny-http-transfers), realtime data streams (use SignalR/MQTT), or push-driven sync (use shiny-push to trigger PullNow).