# actor-framework/actor-framework

An Open Source Implementation of the Actor Model in C++

Repository: https://github.com/actor-framework/actor-framework
Canonical: https://ross.abutalabs.com/products/actor-framework
Homepage: http://actor-framework.org/
Language: C++
License: BSD-3-Clause
License Family: permissive
Topics: actor-model, caf, pattern-matching, actors, async
Last push: 2026-08-26T08:24:38+00:00

## Health v2 (maintenance only)
Score: 67/100 (v2, computed 2026-09-02T17:46:02.011165+00:00)
- activity 99, release rhythm 8, longevity 100
- inputs: {"age_days": 5661, "days_push": 7, "days_rel": 434, "gap_med": 238, "n_releases_24m": 2}
- flags: none
- formula: round(0.45*activity + 0.35*rhythm + 0.20*longevity); archived -> min(score, 10)

## Adoption (not part of the score)
Stars 3432, forks 572 (observed 2026-08-28T04:08:04.060610+00:00)

## What it is
CAF (C++ Actor Framework) is an open-source implementation of the Actor Model in C++, providing lightweight actors, network-transparent messaging, pattern matching, and HTTP/WebSocket support. It enables building scalable, concurrent, and distributed applications with native performance and low memory overhead.

## Use cases
- build concurrent applications in C++ without data races
- implement distributed systems with network-transparent messaging
- write an HTTP or WebSocket server using actors
- scale actors across machines in a data center or cloud
- build low-footprint async software for IoT or embedded devices
- model message-passing systems with pattern matching on messages

## When to choose
- you need high-performance, low-overhead concurrency in native C++
- you want to scale an application from a single machine to distributed deployment
- you prefer the actor model over threads and locks
- you need resilient distributed systems with failover-friendly design

## When to avoid
- your project is in another language or requires a managed runtime
- you need a simple single-threaded application with no concurrency
- you want batteries-included web frameworks rather than a messaging runtime
- your team is unfamiliar with actor-model thinking and cannot invest in learning it

## Facets
- artifact type: framework
- maturity: stable
- function: concurrency, rpc, http-server, websocket, message-queue, middleware
- domain: microservices, developer-tools, backend
- platform: cpp, cross-platform, windows, embedded
- tags: actor-model, caf, pattern-matching, distributed-actors, async, concurrent-programming, real-time, linux, macos

## Member repositories
- actor-framework/actor-framework (main) score 67

## Provenance
- Observed fields: from GitHub, fetched 2026-08-28T04:08:04.060610+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 2026-08-29T18:37:44.716934+00:00, confidence not recorded.
  - readme: https://github.com/actor-framework/actor-framework (fetched 2026-08-28T04:08:04.060610+00:00, sha 7f7a6b918c99)
  - homepage: http://actor-framework.org/ (fetched 2026-08-29T09:31:52.465745+00:00, sha fb6b88b1734c)
  - site_page: https://www.actor-framework.org/index.html (fetched 2026-08-29T09:31:52.474751+00:00, sha 7396b8ec069c)
  - site_page: https://www.actor-framework.org/doxygen (fetched 2026-08-29T09:31:52.476687+00:00, sha 4817b3579ea2)
- Data as of 2026-08-30T08:39:29.467469+00:00.