Speed of Crystal
$ time crystal hello_world.cr Hello World! real 0m1.108s user 0m1.268s sys 0m0.271s
$ time crystal build hello_world.cr -o hw real 0m1.108s user 0m1.323s sys 0m0.238s
$ time ./hw Hello World! real 0m0.013s user 0m0.001s sys 0m0.011s