Azure Service Bus vs MassTransit: What are the differences?
What is Azure Service Bus? *Reliable cloud messaging as a service (MaaS) *. It is a cloud messaging system for connecting apps and devices across public and private clouds. You can depend on it when you need highly-reliable cloud messaging service between applications and services, even when one or more is offline.
What is MassTransit? Lightweight message bus for creating distributed applications. MassTransit is free software/open-source .NET-based Enterprise Service Bus software that helps Microsoft developers route messages over MSMQ, RabbitMQ, TIBCO and ActiveMQ service busses, with native support for MSMQ and RabbitMQ.
Azure Service Bus and MassTransit belong to "Message Queue" category of the tech stack.