I really like where this is going! I've always been a great fan of adding more structural modeling to programming.

How do you see real applications being managed in this system? The tour doesn't touch on this. The included examples are quite abstract, perhaps even too much as they don't really engage me -- I can't imagine caring about how many times a "length" function is used globally. If anything, that example gave me an uncomfortable vibe of the Node.js "left-pad" drama... Sharing code in ridiculously small units just doesn't solve any productivity problems I've experienced.

The stuff about abstract types and function shapes is certainly intellectually interesting, but I'd encourage you think in terms of larger assemblies of code. (Maybe you already are -- I do understand that this is an early demo and you want to get the core right.)