AcornJS
A small, fast, Javascript-based JavaScript parser.
On GH
https://github.com/acornjs/acorn
JS interpreters
Enables to write custom javascript sub-interpreters.
https://github.com/NeilFraser/JS-Interpreter
On NPM
https://www.npmjs.com/package/js-interpreter
Demo
https://neil.fraser.name/software/JS-Interpreter/