PrairieLearn
PrairieLearn is an online problem-driven learning system for creating homeworks and tests. It allows questions to be written using arbitrary HTML/JavaScript, thus enabling very powerful questions that can randomize and autograde themselves, and can access client- and server-side libraries to handle tasks such as graphical drawing, symbolic algebra, and student code compilation and execution.
Documentation website: http://prairielearn.readthedocs.io/