siokit

Socket.IO-compatible server & client library written in TypeScript, supporting Engine.IO v4 (WebSocket and HTTP long-polling) and Socket.IO protocol with typed events, namespaces, acknowledgements, and binary attachments. Current stable version is 0.1.5 with moderate release cadence. Key differentiators: runtime-agnostic (Bun, Hono, Node.js via adapters), zero runtime dependencies beyond its own sub-packages (siokit-core, siokit-parser), and full TypeScript types. Unlike official Socket.IO, siokit is lightweight and adapter-based, making it suitable for serverless and edge environments.