There is a toggle between blocks and javascript in MakeCode. You can write code in blocks and switch to javascript or vice versa. This dual modality hopefully helps students to make the jump from blocks to javascript on a long term.
The first step is to get the runtime and interpreter running. Next step is to bring the jit up.
Chakra is the hybrid engine where we have the interpreter, simple jit and full jit. The interpreter is the one which does all the profile data collection. Profile data is required to get the quality jit code.