Ably Realtime Data Platform

Ably is a realtime data delivery and messaging platform providing infrastructure for building realtime applications at internet scale. Founded in 2014 by Paddy Byers (CTO) and Matthew O'Riordan (CEO) in London, United Kingdom. Raised over $122 million from Insight Partners, Digital+ Partners, Oxx. Serves over 250 million connections monthly for Bloomberg, HubSpot, Toyota, Mizuho. Key features: pub/sub messaging: global pub/sub infrastructure. Publish events to channels, subscribers receive in real-time. Fan-out (one-to-many). Guaranteed ordering: strict ordering per-channel, per-connection. Message history: retrieve from durable storage. Replay missed messages after reconnection. Presence: track online clients with enter, leave, update events. State synchronization. Channel namespaces: organize with namespaces for access control and quotas. Push notifications: native APNs (iOS), FCM (Android), web push directly. Reactor: serverless functions processing realtime events. Trigger AWS Lambda, Google Cloud Functions, Azure Functions, HTTP webhooks. Stateful Reactors maintain state. Connections: multiplex multiple channels over single connection. Automatic reconnection with backoff. State recovery: resume connections, recover messages lost during disconnection. SDKs: JavaScript, TypeScript, Python, Ruby, Java, Go, PHP, Swift, Kotlin, C, .NET, React Native. Binary protocol (MsgPack). REST fallback. Global edge: 18 core routing data centers with edge POPs. Sub-100ms latency globally. 99.999 percent uptime SLA. JavaScript/Go. Proprietary.