It seems to be about standardising communication between desktop applications using an RPC broker server (Plexus Interop). It’s aimed at traders, who often use multiple desktop applications (for trading, news, comms) in various runtimes (Java, C#, Python, etc). This tool is some at creating a standard platform enabling those other tools to communicate with each other. I guess like a sort of cross-runtime service bus with service discovery.

(I don’t work in FS, this is just what I can gather from reading the docs).