What are some alternatives?
Dillinger - joemccann has 95 repositories available. Follow their code on GitHub.
Visual Studio Code - Build and debug modern web and cloud applications, by Microsoft
StackEdit - Full-featured, open-source Markdown editor based on PageDown, the Markdown library used by Stack Overflow and the other Stack Exchange sites.
Sublime Text - Sublime Text is a sophisticated text editor for code, html and prose - any kind of text file. You'll love the slick user interface and extraordinary features. Fully customizable with macros, and syntax highlighting for most major languages.
Bear - Bear is a flexible writing app for crafting notes and prose.
Vim - Highly configurable text editor built to enable efficient text editing