# dunglas/mercure

🪽 An open, easy, fast, reliable and battery-efficient solution for real-time communications

Repository: https://github.com/dunglas/mercure
Canonical: https://ross.abutalabs.com/products/mercure
Homepage: https://mercure.rocks
Language: Go
License: AGPL-3.0
License Family: copyleft
Topics: api, web-api, server-sent-events, subscriptions, golang, hypermedia, graphql, push, streaming-api, mercure, realtime, realtime-api, websocket, async-api, hacktoberfest, caddy
Last push: 2026-08-26T09:46:07+00:00

## Health v2 (maintenance only)
Score: 90/100 (v2, computed 2026-09-03T02:39:23.370411+00:00)
- activity 99, release rhythm 74, longevity 100
- inputs: {"age_days": 2972, "days_push": 7, "days_rel": 93, "gap_med": 0.0, "n_releases_24m": 63}
- flags: none
- formula: round(0.45*activity + 0.35*rhythm + 0.20*longevity); archived -> min(score, 10)

## Adoption (not part of the score)
Stars 5300, forks 346 (observed 2026-08-28T04:09:15.305013+00:00)

## What it is
Mercure is an open protocol (with an IETF Internet-Draft) for pushing real-time updates to browsers and HTTP clients over Server-Sent Events, plus a production-grade reference hub written in Go. It serves as a fast, battery-efficient alternative to WebSockets, with JWT-based authorization, topic selectors, and Last-Event-ID replay.

## Use cases
- push real-time updates from a web API to browsers and mobile apps
- stream LLM tokens and AI agent progress to users
- add GraphQL subscriptions or async capabilities to REST APIs
- build live dashboards and notifications
- implement collaborative editing and Hotwire/Turbo Streams page updates
- broadcast events to IoT devices over plain HTTP

## When to choose
- you need server-to-client push over HTTP/SSE without client-side SDKs
- you want automatic reconnection, replay, and JWT-secured private updates
- you need a self-hostable or managed real-time layer with Docker/Kubernetes support
- you're streaming LLM responses or agent steps like ChatGPT-style APIs

## When to avoid
- you need bidirectional, client-to-server streaming (use WebSockets)
- you require multi-node clustering on the free community edition (clustering transports are paid/Enterprise)
- your project cannot comply with the AGPL-3.0 license

## Facets
- artifact type: service
- maturity: stable
- function: http-server, websocket, middleware, auth, monitoring, api-framework
- domain: web-development, apis, backend, large-language-models
- platform: windows, self-hosted, cloud, go
- tags: server-sent-events, sse, mercure, realtime, push-updates, event-streaming, llm-streaming, hypermedia, caddy, jwt-authorization, real-time, linux, macos, docker, kubernetes

## Member repositories
- dunglas/mercure (main) score 90

## Provenance
- Observed fields: from GitHub, fetched 2026-08-28T04:09:15.305013+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 2026-08-29T17:59:08.848213+00:00, confidence not recorded.
  - readme: https://github.com/dunglas/mercure (fetched 2026-08-28T04:09:15.305013+00:00, sha 47632071570b)
  - homepage: https://mercure.rocks (fetched 2026-08-29T08:53:59.625749+00:00, sha c4b2bcad5adc)
  - site_page: https://mercure.rocks/docs/1.0 (fetched 2026-08-29T08:53:59.628342+00:00, sha 21e25281bcd7)
  - site_page: https://mercure.rocks/docs (fetched 2026-08-29T08:53:59.630079+00:00, sha 44271ccdd2d9)
  - site_page: https://mercure.rocks/docs/ecosystem/awesome (fetched 2026-08-29T08:53:59.633229+00:00, sha 1a4d8904e124)
  - site_page: https://mercure.rocks/docs/getting-started (fetched 2026-08-29T08:53:59.635856+00:00, sha 58d7a489c043)
  - site_page: https://mercure.rocks/docs/hub/cluster (fetched 2026-08-29T08:53:59.638075+00:00, sha bc28a300d9ed)
  - site_page: https://mercure.rocks/docs/ecosystem/help (fetched 2026-08-29T08:53:59.640073+00:00, sha fa5a057e1910)
  - site_page: https://mercure.rocks/docs/hub/install (fetched 2026-08-29T08:53:59.641997+00:00, sha be78649d71ba)
  - site_page: https://mercure.rocks/pricing (fetched 2026-08-29T08:53:59.631626+00:00, sha 03d5f7fa84c9)
- Data as of 2026-08-30T08:39:29.467469+00:00.