Faye

Faye is a self-hosted publish-subscribe messaging system built on Bayeux, with server components for Node.js and Ruby and clients for web browsers. It suits teams that want to manage application messaging themselves; its transport flexibility is useful, but security configuration and deployment topology need deliberate attention.

Overview

Faye supplies the pieces for running message delivery in your own environment rather than a hosted broker. Browser clients rely on a Faye server to relay messages, and delivery guarantees are configurable. That arrangement gives application teams control over how messaging is integrated, but leaves operation and protection of the service to them.

Connection options include WebSocket, HTTP long-polling, Cross Origin Resource Sharing, and JSON-P callback-polling. The browser client retries periodically after a connection loss and can redeliver dropped messages, which helps applications recover from interruptions. This is not a substitute for choosing suitable delivery behavior for the application.

Key features

• Node.js and Ruby servers: Installation is available through npm for Node.js and RubyGems for Ruby, with clients for servers and major browsers. Faye is a natural fit when either server ecosystem is already part of the application stack.
• Message extensions: Server and client extensions can intercept and modify messages as they arrive or leave. They can also implement subscription authentication, giving teams a place to enforce application-specific access rules.
• Monitoring API: The API reports handshakes, subscriptions, unsubscriptions, publishes, and disconnections. These events provide useful visibility into client activity without changing the basic messaging model.
• Browser connection management: Browsers limit connections per host, so the documentation advises using one client for each target server. Applications connecting to multiple servers should account for that constraint in their client design.

Pricing

Faye is free and open source under the Apache 2.0 license. Its Faye plan costs nothing and has no paid tier in the stated offering, so there is no seat or usage allowance to weigh against a subscription price.

Platforms

Faye supports Linux, macOS, Windows, web clients, and self-hosted deployment. The server implementations target Node.js and Ruby; browser clients need a Faye server to handle delivery between clients. This makes it suitable for teams running their own server infrastructure, not for a browser-only setup expecting messaging to work without a backend.

Who it's for

Faye fits developers who need browser messaging connected to Node.js or Ruby services and want control over transports, extensions, and delivery configuration. It is less suitable for teams seeking a managed service or a straightforward deployment across several front-end servers without additional setup.

Pros and cons

Pros

• Several transport choices: WebSocket, long-polling, CORS, and JSON-P callback-polling give applications different connection approaches.
• Useful extension points: Intercepting messages enables application-specific processing, including subscription authentication.
• Free, open-source deployment: The Apache 2.0 license and self-hosted model avoid a software subscription.
• Activity monitoring: Handshakes and message-related client events can be reported through the monitoring API.

Cons

• Default access is permissive: Cross-domain access and unrestricted publishing and subscribing are enabled by default, so deployments need application-appropriate restrictions. HTTPS is advised to protect messages and HTTP transport from eavesdroppers.
• Default engine is single-process: The in-process engine cannot run one Faye service across multiple front-end web servers. Distributed deployments require a separate Redis or Couchbase engine.
• Browser clients require server infrastructure: Faye does not provide browser-to-browser delivery on its own; a Faye server must relay messages.

Alternatives

Choose Lightstreamer if its demo license cap of 20 concurrent client connections fits a small evaluation, or if you need a freemium option with a free trial and broader listed platform coverage, including Android and iOS.

EMQX is worth comparing if you want a serverless option with a free monthly quota of up to 1,000 connections and usage-based charges beyond that quota.

HiveMQ MQTT Broker may suit readers looking for a broker with a Lab plan capped at 100 connections and 100 messages per second; its Launch plan is priced at $299 a month.

For a self-managed, free broker with community-based best-effort support, consider RabbitMQ.

TIBCO FTL is another option with a free Community Edition download for Windows, Linux, and macOS.

Apache Artemis is a free, self-hosted broker requiring Java 17 or later, while Eclipse Mosquitto offers core MQTT features for on-premises use.

If you want an open-source messaging library with no dedicated broker required, choose ZeroMQ.

Browse Message Broker Software for more options.

Verdict

Faye is a strong fit for Node.js or Ruby teams that want a free, extensible way to connect browser clients through a self-hosted Bayeux server. Its transport variety and message hooks are compelling when teams can secure and operate the service themselves. Look elsewhere if permissive defaults, the single-process engine, or the need to provide your own server make it a poor match for your deployment.