Turtle Shell is a simple, unnofficial shell I'm working on. It's missing several core features as of yet (such as running executables,) but it's still a pretty neat project.
After cloning the repo, run npm install to fetch the dependencies and then use node . to run. Make sure the typescript has compiled first or it won't run.
P.S: This is configured so that tsc is in watch mode.
Refer to the wiki for more info.