Hi there, I'm Julius. I made the RunSwift website!
I also create mobile apps for startups and small businesses.
BUT I'M GUESSING YOU WANT TO KNOW A LITTLE BIT MORE ABOUT RUNSWIFT
RunSwift is a pretty cool project. It consists of two Sinatra apps, one for the client-side web application and another for serving Swift compilation requests. The former runs on Heroku; the latter runs on a Mac Mini hosted by the fine folk at MacStadium.
The compilation server is a threaded Sinatra app that does basic security scans on the supplied source code before passing it off to a couple of bash scripts. One bash script is responsible for compiling the Swift code using the standard compiler from Apple & the other is responsible for running the compiled executable in sandbox and returning the standard output.
These two servers talk to each using a JSON API layer.