# crossbario/crossbar

Crossbar.io - WAMP application router

Repository: https://github.com/crossbario/crossbar
Canonical: https://ross.abutalabs.com/products/crossbar
Homepage: https://crossbario.readthedocs.io/
Language: Python
License: NOASSERTION
License Family: other
Topics: websocket, wamp, messaging, mqtt, rest, server, broker, networking-stack, networking
Last push: 2026-07-27T05:17:19+00:00

## Health v2 (maintenance only)
Score: 95/100 (v2, computed 2026-09-02T17:46:02.011165+00:00)
- activity 94, release rhythm 93, longevity 100
- inputs: {"age_days": 4706, "days_push": 37, "days_rel": 47, "gap_med": 25, "n_releases_24m": 4}
- flags: no_license
- formula: round(0.45*activity + 0.35*rhythm + 0.20*longevity); archived -> min(score, 10)

## Adoption (not part of the score)
Stars 2064, forks 278 (observed 2026-08-28T04:06:10.006665+00:00)

## What it is
Crossbar.io is an open-source application router implementing the WAMP protocol over WebSocket, plus REST/HTTP and MQTT bridging, for building distributed and microservice applications. It provides pub/sub and routed RPC messaging with a scalable, secure networking stack.

## Use cases
- route pub/sub and RPC messages between microservices
- build real-time applications with WebSocket messaging
- bridge MQTT and REST clients to a WAMP network
- self-host a message broker for distributed apps
- connect frontend and backend services over WAMP

## When to choose
- you need WAMP pub/sub and routed RPC in a polyglot microservice architecture
- you want a single router bridging WebSocket, MQTT, and REST/HTTP
- you need a scalable, self-hosted real-time messaging backbone

## When to avoid
- you only need simple REST APIs without pub/sub or RPC
- you are locked into a broker like Kafka or RabbitMQ for event streaming
- you need a lightweight embedded message bus rather than a standalone router

## Facets
- artifact type: service
- maturity: active
- function: message-queue, websocket, rpc, http-server, middleware, routing
- domain: microservices, web-development, backend
- platform: python, cross-platform, self-hosted
- tags: wamp, pubsub, mqtt, rest-bridge, application-router, microservices, messaging, real-time, linux, docker

## Member repositories
- crossbario/crossbar (main) score 95

## Provenance
- Observed fields: from GitHub, fetched 2026-08-28T04:06:10.006665+00:00.
- Health v2: computed from the inputs above; adoption is never an input.
- Inferred fields (summary, facets, guidance): AI-extracted, prompt v1, taxonomy v1, on 2026-08-30T02:57:08.228294+00:00, confidence not recorded.
  - readme: https://github.com/crossbario/crossbar (fetched 2026-08-28T04:06:10.006665+00:00, sha 7e2b106175ee)
  - registry_pypi: https://pypi.org/pypi/crossbar/json (fetched 2026-08-29T10:38:00.305198+00:00, sha fb597c26e866)
- Data as of 2026-08-30T08:39:29.467469+00:00.