Almost the entire app was written in Javascript, with JSON-based configuration and data storage. The following components were written and/or configured with Javascript:

• Most server-side scripts, all unit tests, all build tools, etc. were driven by NodeJS.
• ExpressJS served as the 'backend' server framework.
• MongoDB (which stores essential JSON) was the main database.
• MongooseJS was used as the main ORM for communicating with the database, with KnexJS used for certain edge cases.
• MochaJS, ChaiJS, and ExpectJS were used for unit testing.
• Frontend builds were done with Gulp and Webpack.
• Package management was done primarily with npm - with a few exceptions that required the use of Bower (also configured with JSON).
• "Templating" was done with Javascript dialect JSX.
• The frontend was build primarily with ReactJS (as the View) and Redux (as the Controller / Store / frontend model).
• Configuration was done with json files.

The only notable exceptions were the use of SCSS (augmented by Compass) for styling, Bash for a few basic 'system chores' and CLI utilities required for development of the app (most notably git and heroku's CLI interface), and a bit of custom SQL for locations where the ORM extractions leaked (the app is DB-agnostic, but a bit of SQL was required to fill gaps in the ORMs when interfacing with Postgres). JavaScript