SocketCluster
SocketCluster is a server environment for building real-time applications over HTTP and WebSocket.
What SocketCluster is
SocketCluster is a server environment for building real-time applications over HTTP and WebSocket. It supports pub/sub and RPC systems, including chat and multiplayer games, and is designed to scale across processes on one machine or across multiple machines and instances. Pub/sub channels are cleaned up when unused and can support millions of unique channels. Asynchronous socket-stream operations preserve processing order, while server methods let operators monitor inbound and outbound backpressure. JWT is the default authentication method, with HTTP and WebSocket flows also supported. Middleware can block connections or socket actions, or delay and transform packets between clients and server. After a connection drops, channels remain pending and automatically resubscribe when the client reconnects. SocketCluster is self-hosted and MIT-licensed, with a free plan at no cost. The maker lists clients for JavaScript, Java/Android, Python, .NET, Go, Swift/iOS, Ruby, and Unity, and documents Kubernetes deployment options.
Good
- Supports HTTP and WebSocket
- Scales across processes and machines
- Reconnects clients to pending channels
- MIT-licensed free plan
- Client libraries span several languages
Watch out
- Self-hosted deployment requires operating the service
- Getting-started guide lists Node.js v10 as a requirement
- Ordering is guaranteed per queue
Who it suits
SocketCluster suits developers building real-time chat, multiplayer, pub/sub, or RPC systems who want to host their own deployment. It can serve projects that need clients across web and mobile platforms.
Verdict
SocketCluster offers real-time server capabilities and self-hosted deployment without a listed paid plan. Check the per-queue ordering scope and deployment requirements against your application needs.
Plans and prices
From SocketCluster's own pricing page, checked 8 Oct 2026.
| Plan | Price | What it gives you |
|---|---|---|
| SocketCluster | Free | MIT licensed · self-hosted deployment · Open-source software; no paid plans are listed on the maker’s site. |
The facts
Each one read from SocketCluster's own pages, with the date it was checked.
What it does
- Access control
- Middleware streams can block connections and socket actions, and can delay or transform packets sent between client and server.checked 8 Oct 2026
- Authentication
- JWT is the default authentication mechanism, with HTTP-based and WebSocket-based flows supported.checked 8 Oct 2026
- Channels
- The maker says pub/sub channels are lightweight, automatically cleaned up when unused, and can support millions of unique channels.checked 8 Oct 2026
- Client libraries
- The maker’s site lists JavaScript, Java/Android, Python, .NET, Go, Swift/iOS, Ruby, and Unity clients.checked 8 Oct 2026
- Deployment
- The CLI provides Kubernetes shortcut commands, and the maker provides Kubernetes deployment YAML files.checked 8 Oct 2026
- Integrations
- The documentation describes running SocketCluster with frameworks such as Express and deploying it on Kubernetes inside Docker containers.checked 8 Oct 2026
- License
- The SocketCluster repository states that the project is distributed under the MIT License.checked 8 Oct 2026
- Message handling
- Asynchronous operations in socket streams preserve message processing order, and the server exposes methods to monitor inbound and outbound backpressure.checked 8 Oct 2026
- Purpose
- SocketCluster is an HTTP and WebSockets server environment for building scalable, multi-process real-time systems such as pub/sub and RPC applications.checked 8 Oct 2026
- Reconnect behavior
- When a client loses its connection, its channels enter a pending state and automatically resubscribe after reconnection.checked 8 Oct 2026
- Requirements
- The getting-started guide lists Node.js v10 as a requirement and Docker CLI and kubectl as optional dependencies.checked 8 Oct 2026
- Scaling
- It is designed to scale vertically across processes and horizontally across machines or instances.checked 8 Oct 2026
- Support
- The maker’s site links to community chat on Gitter and provides documentation and an API reference.checked 8 Oct 2026
- Use cases
- The maker describes SocketCluster as suitable for chat systems and multiplayer online games.checked 8 Oct 2026
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