Electric DB Ltd., trading as ElectricSQL, is a specialized infrastructure company headquartered in Croatia. Founded in 2021 by a team of distributed systems experts and open-source pioneers, the company develops high-performance synchronization technology for the "local-first" software movement. ElectricSQL provides an open-source sync engine that connects central PostgreSQL databases to local, embedded databases in web and mobile applications. By moving the "source of truth" for the application state onto the user's device while maintaining background synchronization with the cloud, ElectricSQL enables developers to build apps that are instantly reactive, collaborative, and capable of operating entirely offline.
The Local-First Software Paradigm
ElectricSQL operates at the forefront of the "local-first" movement. Traditional cloud-first applications rely on a Request-Response model (REST or GraphQL) where every user interaction involves a network round-trip to a server. This leads to latency, "loading spinners," and failure in offline scenarios.
ElectricSQL reverses this architecture. In an Electric-powered app, the frontend code interacts directly with a local database (like PGlite or SQLite) residing on the device. The "sync engine" handles the heavy lifting of replicating data subsets from a central Postgres instance to the device and back, ensuring data consistency across multiple users and devices without requiring the developer to write complex WebSocket or polling logic.
Core Technology and Products
1. The Electric Sync Engine
The core of the company?s offering is the Electric Sync Engine. Developed primarily in Elixir to leverage the high-concurrency capabilities of the Erlang VM (BEAM), the engine sits in front of a standard PostgreSQL database. It uses Postgres logical replication (WAL) to detect data changes in real-time and stream them to connected clients.
- Shape-Based Sync: Instead of syncing an entire multi-terabyte database to a mobile phone, Electric uses a primitive called "Shapes." A Shape is a defined subset of the database?specified by a table and a set of filters?that a client "subscribes" to.
- HTTP-Based Delivery: Unlike legacy sync solutions that require persistent WebSockets, Electric streams data over standard HTTP. This allows the sync stream to be cached by CDNs (Content Delivery Networks), enabling the system to scale to millions of concurrent users with minimal server load.
2. PGlite (Postgres in the Browser)
ElectricSQL developed PGlite, a groundbreaking, lightweight WASM (WebAssembly) build of PostgreSQL. PGlite allows developers to run a full, reactive Postgres database directly in a browser's memory or persistent storage (IndexedDB).
* Zero-Dependency: It is a single JavaScript package under 3MB (gzipped).
* Live Queries: It supports reactive "live queries," where the UI automatically updates the moment the underlying data changes, whether that change came from a local user action or a sync event from another device.
3. Electric Cloud
For enterprises and startups that do not wish to manage their own infrastructure, Electric DB Ltd. offers Electric Cloud. This is a fully managed "Sync-as-a-Service" platform that handles the deployment, scaling, and maintenance of the sync engine. It integrates natively with popular Postgres hosting providers like Supabase, Neon, and AWS RDS.
4. TanStack DB Integration
In collaboration with the creators of TanStack (React Query), ElectricSQL offers an integrated "sync stack" for modern web development. This provides a type-safe, reactive client layer that manages normalized data flows, allowing developers to treat the remote database as if it were a local variable.
Technical Features and Services
Read-Path Optimization
ElectricSQL focuses heavily on "read-path" synchronization. It treats data delivery as a replication problem rather than an API problem. By using a "pull-based" approach where clients track their own "offset" in the data stream, the server remains stateless and highly scalable.
Conflict Resolution (CRDTs)
To handle the complexities of multi-user collaboration (e.g., two people editing the same record while offline), ElectricSQL utilizes Conflict-free Replicated Data Types (CRDTs). This technology, developed in collaboration with researchers from LIP6 and INESC-ID, ensures that all replicas of the data eventually converge to the same state without requiring a central coordinator to resolve manual conflicts.
Security and Authorization
ElectricSQL integrates with existing authentication providers. Because sync happens over HTTP, developers can place an "Authorization Proxy" in front of the sync engine. This proxy inspects incoming requests for "Shapes" and ensures the user has the appropriate permissions (using Row Level Security or custom logic) before allowing the data to stream.
Leadership and Company Background
The company was co-founded by:
* James Arthur (CEO): Previously co-founder of Opendesk and Hazy.
* Valter Balegas (CTO): A researcher with a PhD in distributed systems, specifically focused on consistency and CRDTs.
* Kyle Mathews: The founder of Gatsby (acquired by Netlify), who joined the leadership team to drive the 1.0 "clean re-write" of the sync engine in 2024.
The entity is backed by prominent venture capital firms, including Spark Capital, Lunar Ventures, and StepFunction, as well as industry angels like Jos? Valim (the creator of the Elixir programming language). While the core team is based in Croatia, the company operates with a global presence, supporting an active open-source community of thousands of developers.
