Deku - Functional view library for building UI components as an alternative to React
Monosnap - Monosnap is a comprehensive screenshot taking software system that provides users with a fast and accessible way to take screenshots whenever they want. Read more about Monosnap.
Preact.js - Preact is a fast 3kB alternative to React with the same modern API. Components & Virtual DOM.
LabelMe Annotation Tool - LabelMe is an annotation tool writen in Javascript and Perl for online image labeling.
Glimmer - Fast and light-weight UI components for the web
Greenshot - Greenshot is a free and open source screenshot tool that allows annotation and highlighting using the built-in image editor.