Nice, I'll have to take a look at Alu. I'm also aware of Coalton. It's very cool in principle, though I have not used it (yet?). The original proof-of-concept

Nice, I'll have to take a look at Alu. I'm also aware of Coalton. It's very cool in principle, though I have not used it (yet?). The original proof-of-concept was written in Common Lisp, and development of core language features often happens in that version. It's more flexible for rapid development, and the 'API' can be taken it at a glance a bit more simply. Having multiple implementations also has the benefit of keeping us honest (at the cost of some hopefully-ephemeral drift and maintenance).