From: https://github.com/dwyl/start-here/blob/8bbd28d2ab0c3b5a2a266a1e41fd160fc6ee3038/README.md#software

Installing software is 100% optional. You can use Cloud9 to develop completely online: https://c9.io/

If you prefer to develop offline or have a faster response, you will need:

• A text editor. e.g. Atom
• Node.js for building server-side apps.