What kind of servers do you use? what are the specs :P
You use a server service as AWS or Digital ocean??
Short answer: We're using both Google Cloud and Heroku
The website itself is hosted on a PaaS (platform as a service) called Heroku (which uses AWS under the hood), the reason we chose that is because we're a small team and it didn't make sense to allocate resources to managing our own infrastructure for a basic web server.
Our code compilation/evaluation/hosting infrastructure are on Google Cloud. Google cloud is similar to AWS as it's a IaaS (infrastructure as a service). It gives the full control that we need since this part of our stack isn't as simple as just running a webserver. If you're more interested in what kind of things we do on GC, @turbio is the person to ask.