shanhu.io is a programming playground powered by e8vm:
https://github.com/e8vm/e8vm
e8vm is an open-source self-contained simulated virtual machine that has its own simple mips-like instruction set, and its own system programming language (G language). G is a language that has a golang-like syntax but with a c-like runtime -- no runtime.
shanhu.io provides an online playground where you can develop G language programs and run it in a simulated e8vm virtual machine right in your browser. The website requires a github account to login to save the workspaces.
The entire project is written in Go language, with no circular dependencies among files and packages, with each file no more than 300 lines (maximum 80 chars each). As a result, the project can be visualized in a hierarchy of DAG's:
https://e8vm.io/e8vm
The G language compiler enforces the same dependency rules, so a small operating system in G (still in development) can also be visualized:
https://shanhu.io/~os8
It is a hobby project of mine. Questions and feedbacks are welcomed. :)