Make a secret or black box function?

Suppose my function was f(x,y) = x^2+sin(y). Can you use this as an example to tell me how to use IRTools to generate some intermediate representation that is directly callable? I looked at the README for IRTools; I could see how code was turned into some “lower level” julia, but it wasn’t clear to me how to call/use that lower level stuff. In the README, I didn’t fully understand

julia> f = IRTools.func(ir); # Turn the new IR into a lambda

julia> f(nothing, 10, 5)

though that seems to be what I want to do: just cut and paste the output of @code…except that only works if you give arguments to it. Can I not define a function with the intermediate representation? If I gave that to a student, they’d be able to use it but not really understand it (i.e., black box).