I originally make this site because I wanted to track my own progress as a sc2 1v1-player. I wanted to see my rank relative to other players and the leagues changes too much for this.
Too see progress data over time is needed so I started to collect ladder data using the Battle.net API. Unfortunately it was not possible to get all information from the beginning of time as I wanted so the first data is from season 5 2013. Sc2ranks.com already had something similar but only showed the current and last season. Also it was a fun programming project. The passion for programming is event bigger than the passion for StarCraft.
All rankings are based on league and points, not MMR since Blizzard is not public about that. It would be possible to estimate MMR if match history API provided points won and lost, but unfortunately it does not. The rankings would also be more accurate if points given by bonus pool where subtracted, but bonus pool information is not available either. :(
The site is built using Python and Django and runs on GNU/Linux with Nginx as web server and Postgresql as database. There is also quite a bit of c++ code in there, it turns out looking up complete ranking history among 3 million teams over a couple of years is a challenge on a 2 GB memory box. =)