N1 is an open-source mail client built on the modern web with Electron, React, and Flux. It is designed to be extensible, so it's easy to create new experiences and workflows around email. N1 is built on the Nylas Sync Engine which is also open source free software.
You can download compiled versions of N1 for Mac OS X and Linux from https://nylas.com/N1. You can also build and run N1 on Windows. A Windows distribution is coming soon!
Plugins lie at the heart of N1 and give it it's powerful features. Building your own plugins allows you to integrate the app with other tools, experiment with new workflows, and more. Follow the Getting Started guide to write your first plugin in 5 minutes.
If you would like to run the N1 source and contribute, check out our contributing guide