Hi,
I recognize several aspects of the project language off the cuff - 'actors' will be referring to Akka, and designing a multithreaded application. JSON parsing is pretty standard, this is using an implicit serializer/deserializer. The HTML and CSS frontend is boilerplate, a junior can do this ( and in fact it looks like the repository contains most of the needed design already )
May I assume you need this done within a day or two? I can do a rush order as you need.
I have worked as a backend engineer using Scala and multithreaded applications for most of my career. I specialize in custom frameworks and solving technical challenges which stump senior engineers.
As such I feel I'm quite able to take this project on.
Let me know if I can start.