Piston is a high performance general purpose code execution engine. It excels at running untrusted and possibly malicious code without fear from any harmful effects. Piston uses Docker as the primary mechanism for sandboxing. There is an API within the container written in Node which takes in execution requests and executes them within the container safely. High level, the API writes any source code to a temporary directory in /piston/jobs. The source file is either ran or compiled and ran (in the case of languages like c, c++, c#, go, etc.).