Feedl is a way to manage the bulk downloading of MP3s for Podcasts via RSS feeds. You can then copy these wherever you'd like so that you can listen to them offline.
To run this locally for development purposes, you'll need to run two commands. Run these in two separate terminals, from the working directory.
npm start
To build your electron app and package it for release:
npm run make
The .dmg file will be in the 'out' folder.