sync_engine

Pure-Dart, immutable CRDT primitives for flutter_sync_engine. It can be tested with dart test and deliberately has no Flutter dependency.

LWW conflict resolution

LWWRegister uses vector clocks for causal order. If two writes are concurrent, it selects the value from the lexicographically greater node ID. That rule is deterministic but arbitrary; applications needing domain-specific resolution should provide it above this primitive.

SyncEngine serializes sync cycles, validates transport acknowledgements, and keeps the outbox cursor from advancing when a push fails. Durable persistence is provided by sync_engine_drift; the core package ships the outbox contract and in-memory implementation.