That's a good idea. Jeff is the real compilers genius so I'll have to see if I can convince him to write a blog post along those lines. The bounds check stuff I mentioned above is one of the important planned optimizations. Another important move is making composite types immutable by default, which is surprisingly unstiffling, yet allows a large number of clever optimizations (stack allocation, memory layout optimizations). More playing around with llvm optimization passes could help and is pretty easy to do, but we haven't spent much time on that. Also lots of gc improvements (approximate ref counting, escape analysis).