FastPubSub is a low-latency messaging platform for real-time delivery across the Internet via optimized network paths.
It is designed for applications where messages must be delivered quickly and reliably to one or many listeners without relying on direct end-to-end connectivity alone.
Traditional Internet routing is not always the fastest path between two endpoints.
In some cases, the direct route is slower. In other cases, it may be unstable, filtered, or blocked by firewall policies, DPI rules, or provider-level routing decisions.
FastPubSub approaches this differently.
Instead of treating the network as a fixed direct path from IP to IP, FastPubSub uses a distributed overlay of edge nodes that continuously measure connectivity and latency between each other. Messages are then forwarded through the fastest currently known path across the overlay.
- Delivers discrete messages instead of raw byte streams
- Supports message sizes up to 64 KB
- Uses virtual channels for writing and reading messages
- Accepts client connections via WebSocket
- Transfers messages between nodes over HTTP/3 / UDP
- Continuously evaluates inter-node latency using active measurements
- Chooses optimized delivery paths across the Internet
- Does not persist messages
FastPubSub is built around a simple idea:
the best path is not always the direct path
A direct connection may look shorter on paper, but real Internet routing is shaped by congestion, peering quality, provider policies, filtering, and geographic asymmetry.
By maintaining a real-time view of node-to-node connectivity, FastPubSub can route messages through a better path when the direct route is slower or unavailable.
FastPubSub is being designed for real-time and low-latency scenarios such as:
- message fan-out
- one-to-many delivery
- many-to-one delivery
- many-to-many real-time messaging
- globally distributed event propagation
- delivery in environments where direct paths are suboptimal
- delivery in environments where direct connectivity may be restricted
Client-facing connections use WebSocket.
Inter-node transport uses HTTP/3 over UDP.
The platform is message-oriented rather than stream-oriented.
This makes it closer in spirit to datagram-style communication than to a classic TCP byte stream, while still operating through a managed overlay network.
FastPubSub is currently designed around:
- low-latency forwarding
- dynamic path optimization
- transient in-flight delivery
- no built-in message persistence
- no durable message history
This is a deliberate design choice. The system is focused on fast delivery, not long-term storage.
FastPubSub is currently in the early prototype / MVP stage.
This repository serves as a public overview of the project.
FastPubSub is being built in Rust.
This repository is intended to provide:
- a public overview of the project
- high-level documentation
- roadmap and status updates
- issue tracking and public feedback
- links to related project resources
Questions, ideas, and feedback are welcome through GitHub Issues.