The purpose of trprt.io is to teach code literacy — not just the ability to write code, but also to read it. Currently it's a collection of exercises that generate random programs which you must read to determine their output. If you make an account, you can track your scores so that you can tell whether you're getting better.
In the future, trprt may be expanded to contain lessons with the exercises integrated into them, a wider variety of exercises, and more languages. If you have a suggestion or comment, please contact me.
For more information, check out the FAQ.
I built trprt.io after working as a programming tutor for 7 years. My experience tutoring students, mostly beginners, taught me that the reason most students can't write code is that they don't know how to read it. Unfortunately, reading is barely practiced in most courses.