Fanout vs SocketCluster: What are the differences?

Developers describe Fanout as "Realtime APIs made simple". Fanout makes it easy to build realtime APIs and apps. The product is a cross between a reverse proxy and a message broker. Receivers subscribe to channels, and published data is delivered in realtime. On the other hand, SocketCluster is detailed as "An open, scalable realtime engine for Node.js". SocketCluster is a fast, highly scalable HTTP + realtime server engine which lets you build multi-process realtime servers that make use of all CPU cores on a machine/instance. It removes the limitations of having to run your Node.js server as a single thread and makes your backend resilient by automatically recovering from worker crashes and aggregating errors into a central log.

Fanout and SocketCluster can be primarily classified as "Realtime Backend / API" tools.

Some of the features offered by Fanout are:

• Reverse proxy -- integrate realtime with any level of your technology stack, not just your front end.
• Interoperable -- Add realtime to any API, no matter your backend or database, without changing any of your existing API contracts.
• Open -- cloud or self hosted, it’s up to you. We don’t believe in vendor lock-in.

On the other hand, SocketCluster provides the following key features:

• Resilient on both the client and backend - Process crashes, lost connections and other failures are handled seamlessly.
• Scales linearly as you add more CPU cores and workers (assuming a decent OS) - Tested with up to 16 cores.
• Also designed to scale horizontally across multiple machines. See sc-redis sample.

SocketCluster is an open source tool with 5.35K GitHub stars and 283 GitHub forks. Here's a link to SocketCluster's open source repository on GitHub.