Great idea!

This looks great. Built by CodeFights, which is a great place to work on your programming in a number of languages, with daily challenges, head-to-head battles and company bot battles that can land you jobs at big tech companies like GoDaddy, Uber and DropBox.

This could be a fun way to find new hiring candidates!

this is the real deal

This is the best game you will play today!

Something like Codin Game. I'm up for it!

If the question really gets difficult this is a very good evolution over existing OJs.