Offline-first sync for PocketBase apps.

Deterministic two-way sync runtime with per-user record sandboxing, atomic field-level diffs, and monotonic sequences that eliminate client NTP clock drift vulnerabilities entirely.

Quickstart Guide arrow_forward account_tree View Architecture Spec

$ npm i @pb-sync/client @pb-sync/adapter-expo

SYNC_TELEMETRY // LIVE BUS

SSE_STREAM_ACTIVE

phone_iphone Node A (Expo / SQLite)

SYNCED

Local Rev: #0482

WAL Cache: 0 queued

swap_vert Engine Bus · Delta Batching

0 PENDING MUTATIONS

dns Node B (PocketBase Server)

AUTH_OK

High-Water Mark: seq: 1,842

Outbox Buffer: Auto-deduping

❯ SYNC_EVENT_ACK: tx_89f02c

0 conflicts

Records: 4,128 Reconciler: 0ms drift

[ SYSTEM GUARANTEES ]

Built for disconnected field operations.

01 // LOCAL-FIRST bolt

Instant write latency.

Mutations resolve instantly inside zero-overhead client storage. Writes never freeze awaiting network round-trips. Offline payloads queue persistently inside an atomic transactional ledger.

✔ WAL journaling via SQLite / IDB

02 // DETERMINISTIC MERGES alt_route

Field-level granularity.

Full-record blind overwrites are strictly rejected. Field hashing partitions changes so orthogonal property edits never collide, and conflicting field values fall back to reproducible server logic.

✔ SHA-256 state-hash reconciliation

03 // ZERO CLOCK DRIFT schedule

Authoritative sequences.

No reliance on unpredictable client NTP timestamps or device clocks. Sync checkpoints utilize central server sequence numbers, eliminating time-warp anomalies and ghost revisions forever.

✔ Strict monotonic sequence vector

[ DOCUMENTATION MODULES ]

Explore the integration surfaces

SPECS // PROTOCOL east

Wire Protocol & Atomic Guarantees

Examine the replication lifecycle diagrams, HTTP/SSE handshake state transitions, sandboxed user security boundary tokens, and conflict handling tables.

PATCH /api/sync/v1/pull 200 OK

{ "high_water_seq": 1842, "mutations": [...] }

GUIDES // 5-MIN INTEGRATION east