# MassTransit/MassTransit

Distributed Application Framework for .NET

Repository: https://github.com/MassTransit/MassTransit
Canonical: https://ross.abutalabs.com/products/masstransit
Homepage: https://masstransit.io
Language: C#
License: Apache-2.0
License Family: permissive
Topics: masstransit, rabbitmq, c-sharp, azure-service-bus, messaging, dotnet, nuget, sqs
Last push: 2026-06-04T18:06:31+00:00

## Health v2 (maintenance only)
Score: 70/100 (v2, computed 2026-09-03T02:20:16.233290+00:00)
- activity 85, release rhythm 35, longevity 100
- inputs: {"age_days": 5892, "days_push": 90, "days_rel": null, "gap_med": null, "n_releases_24m": 0}
- flags: no_releases
- formula: round(0.45*activity + 0.35*rhythm + 0.20*longevity); archived -> min(score, 10)

## Adoption (not part of the score)
Stars 7798, forks 1974 (observed 2026-08-28T04:10:05.076610+00:00)

## What it is
MassTransit is a free, open-source distributed application framework for .NET that enables message-based, loosely-coupled asynchronous communication across transports like RabbitMQ, Azure Service Bus, Amazon SQS, and ActiveMQ. It provides a consistent programming model with message contracts, consumers, sagas, retries, outbox, scheduling, and a test harness.

## Use cases
- build microservices with asynchronous messaging in .NET
- implement event-driven communication between services
- add retries, redelivery, and outbox patterns to message processing
- orchestrate long-running workflows and sagas
- schedule delayed messages and jobs
- create a SignalR backplane for scaling out hubs
- interoperate with existing NServiceBus systems
- unit test message consumers without a real broker

## When to choose
- you are building .NET applications that need reliable message-based communication
- you want transport portability across RabbitMQ, Azure Service Bus, SQS, or ActiveMQ with one API
- you need production features like outbox, retries, fault handling, and scheduling out of the box
- you want DI and hosted-service integration so consumers run inside your app

## When to avoid
- you need a simple point-to-point queue with minimal abstraction
- your team works outside the .NET ecosystem
- you require full NServiceBus message exchange compatibility (interop is limited and clean-room built)
- you want a fully free v9 with commercial support included (v9 is a commercial product)

## Facets
- artifact type: framework
- maturity: active
- function: message-queue, rpc, scheduling, workflow-automation, middleware, serialization, testing
- domain: microservices, backend, developer-tools
- platform: dotnet, cross-platform, cloud
- tags: message-bus, saga, event-driven-architecture, rabbitmq, azure-service-bus, amazon-sqs, outbox-pattern, nservicebus-interop, signalr-backplane, messaging, docker

## Member repositories
- MassTransit/MassTransit (main) score 70

## Provenance
- Observed fields: from GitHub, fetched 2026-08-28T04:10:05.076610+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 2026-08-29T17:34:38.430007+00:00, confidence not recorded.
  - readme: https://github.com/MassTransit/MassTransit (fetched 2026-08-28T04:10:05.076610+00:00, sha ea98606d2fa9)
  - homepage: https://masstransit.io (fetched 2026-08-29T08:30:54.885512+00:00, sha af44bb997aa3)
  - site_page: https://masstransit.massient.com/configuration/integrations/nsb (fetched 2026-08-29T08:30:54.894640+00:00, sha 4f693217f217)
  - site_page: https://masstransit.massient.com/configuration/integrations/signalr (fetched 2026-08-29T08:30:54.896916+00:00, sha 9696ae98874d)
  - site_page: https://masstransit.massient.com/reference/obsolete (fetched 2026-08-29T08:30:54.898716+00:00, sha c18497236655)
- Data as of 2026-08-30T08:39:29.467469+00:00.