I'll be back.
This is the E-800 Evaluator. It isn't going to kill Sarah Connor (probably); it's just going to evaluate your code. Create assignments, submit code, and have it run.
This is a Docker multi-container application maintained with Docker Compose.
Metadata is all in docker-compose.yml.
The Web UI, which is 80% or more of the code here, is all Rails.
This uses Postgres by default, but it probably wouldn't be hard to get it on MariaDB or whatever.