To compile the code, open up iex, then
c "manyproc.ex"
This should output [Manyproc], the module's name.
As it's already loaded into iex, simply access its functions by
Manyproc.function_name
Particularly, you will want to run star_and_time with a large paramter, for fun!
Manyproc.start_and_time 100000