tl;dr: If you run a Redis server and currently use Amazon SQS or a similar message queue you might as well use this fast little replacement. Using a shared Redis server multiple Node.js processes can send / receive messages.
RSMQ is a tool in the Message Queue category of a tech stack.
RSMQ is an open source tool with 1.02K Github Stars and 71 Github Forks. Here’s a link to RSMQ's open source repository on Github
Here’s a list of reasons why companies and developers use RSMQ.