Writeups on how to make a basic programming language are coming soon, but for now here's v0.0.5 of Equi: https://github.com/wrbernardoni/Equi
A coding competition, and the start of classes have delayed work on Equi, so right now multithreading is only in the development branch as it is only 50% feature complete. There's a persistent bug when it comes to returning values from completed tasks, but I have the solution figured out, just not the time yet to implement it.
In the meantime Equi is a fun little toy language. As soon as my schedule opens up a bit more I plan on finishing up the core parrallelism of Equi and then moving on to implementing a type system and polymorphism into Equi. For now there's just primitive types but many more features are coming to Equi.