The private beta of GenesisDB Syncra, a new member of the GenesisDB product family, has been open for a few days now. Syncra aggregates multiple event sourcing database instances into a single, deterministic, unified stream. It is built for event-driven architectures that have outgrown a single event store and now span services, teams, and regions.
If GenesisDB is the engine that captures every state change as an immutable event, Syncra is the layer that turns those scattered signals into one coherent flow.
Why event sourcing needs aggregation
Event sourcing works beautifully inside a single bounded context. Every change is an event, every event is the truth, and replay is just a matter of reading the log. But real systems rarely stay inside one bounded context for long.
As event-driven systems grow, they naturally split into multiple bounded contexts, each backed by its own event sourcing database. Orders live in one store, users in another, billing in a third. Each service owns its events, but downstream consumers - dashboards, projections, reporting tools, business flows - often need a combined view across all of them.
The usual answer is custom integration code: one consumer per event store, glued together with bespoke ordering logic and a lot of hope. Syncra replaces that pile of glue with a single, well-defined component.
Three steps. From scattered signals to a single flow.
- Aggregate. Connect Syncra to multiple GenesisDB event sourcing instances across services, teams, or regions. Syncra pulls their event streams into a single, unified in-memory cache.
- Unify. Events from all sources are merged into one deterministic stream, ordered by time. Every event carries its origin instance name, so you keep full traceability across your event sourcing architecture.
- Serve. Expose the merged stream through the same API you already know from GenesisDB. Every event stays CloudEvents compatible. Stream and observe in real time.
One connection instead of many.
One deterministic stream instead of scattered sources. One API for all your event sourcing data. Your existing GenesisDB clients keep working - just point them at Syncra.
Built for event-driven architectures
Whether you run a handful of services or a large-scale event sourcing platform, Syncra fits into your architecture without changing how your services work. A few scenarios where it shines:
- Multi-service event sourcing: When your domain is split across multiple GenesisDB instances, Syncra gives downstream consumers a consolidated view without coupling them to each source.
- Cross-team event streams: Different teams own different event stores. Syncra lets you observe all of them through a single connection, filtered by the subjects you care about.
- Real-time dashboards and projections: Build dashboards, read models, and reporting tools that need a live, unified feed of business events from your entire event sourcing infrastructure.
- Business flow composition: Compose higher-level business flows from low-level event signals spread across independent services and bounded contexts.
Under the hood
Syncra is intentionally narrow in scope and engineered for speed and predictability:
- Deterministic ordering: Events from different instances are merged by time with stable tie-breaking by instance name and event ID. Same input, same output - every time.
- GenesisDB-compatible API: Stream and observe endpoints match the GenesisDB HTTP API. Your existing event sourcing clients just work.
- In-memory, pre-serialized: Every event is JSON-serialized once at ingest time. API responses write pre-encoded bytes directly. Zero re-marshaling on the hot path.
- Real-time SSE: Persistent Server-Sent Event connections to each upstream event store. New events reach observers within milliseconds.
- Instance attribution: Every event carries an
instancefield identifying which event store produced it. Filter, route, or display by source. - Read-only by design: Syncra never writes to upstream instances. It is strictly a consumer and aggregator. Nothing more.
Part of the GenesisDB family - free forever
GenesisDB Syncra is closed source and ships as part of the GenesisDB product family - free forever. No license fees, no per-event pricing, no surprise tiers down the road. We want Syncra to be a natural extension of every GenesisDB deployment, not a paywalled add-on. During the private beta we are working closely with participating teams to shape Syncra around the architectures that actually exist in production.
Join the private beta
If you are running multiple GenesisDB instances - or you are about to - and you have ever wished for a single deterministic stream out of the box, this beta is for you. We are onboarding a small group of teams first, gathering feedback, and iterating quickly.