deepstream.io is an open-source realtime server that synchronizes JSON records, events, and remote procedure calls across clients and backend services. It functions as a realtime data sync server, event pub/sub server, record database server, and RPC server, all within a single platform. The server authenticates and authorizes every message using multiple strategies including JWT, HTTP, and file-based credentials, with a declarative permission language controlling access to records, events, and RPCs at a granular level.
The platform distinguishes itself through its combination of realtime data synchronization, topic-based pub/sub messaging, and remote procedure call orchestration in one integrated system. It supports atomic multi-path updates on JSON records, cross-client data sync, and a listen pattern that notifies backend services when clients subscribe to topics. The server runs on a single-threaded horizontal scaling model, allowing multiple independent nodes to distribute load across cloud instances, and supports plugin-based storage architecture for connecting to external databases and caches.
Beyond its core capabilities, deepstream.io provides online user presence tracking, connected client queries, and RPC request load balancing across multiple registered providers. It offers command-line configuration overrides and supports YAML or JSON configuration files. The server can be registered as a system service on init.d or systemd systems, and supports running multiple server instances on one machine with separate configurations.