FoundationDB

FoundationDB is a distributed, multi-model transactional database designed to run on commodity hardware and scale across large clusters. It provides serializable ACID transactions across a distributed key-value store, enabling complex data access patterns while maintaining strong consistency and fault tolerance.

The core stores data as ordered key-value pairs and supports multi-key transactions, automatic data partitioning, replication, and recovery. Transactions in FoundationDB are executed using a deterministic protocol that detects conflicts and retries automatically, ensuring serializability without requiring explicit locking. The system exposes a simple key-value API and supports higher-level data models through modular layers that run atop the core, allowing developers to build document, graph, or relational-like interfaces.

APIs are available for multiple programming languages, and deployments can be run on-premises or in cloud environments. Administrators can configure replication factor, storage, backups, and observability, while the system handles data distribution, failover, and recovery transparent to applications.

FoundationDB originated as an independent project and later was acquired by Apple. Apple released the core as open-source under the Apache License 2.0 in 2018, and development has continued with contributions from Apple and the community. The project is maintained publicly, with documentation and source code available on official sites and the GitHub repository.

Common use cases include workloads requiring strong consistency across distributed data, such as financial services, identity and metadata stores, and microservice architectures where cross-key transactions are important.