ACDSee - ACDSee is an image viewer that uses very little system resources, and it has a small, sleek size that won't take up much space on your system.
Inferno - An extremely fast React-like javascript library for building modern user interfaces.
Flickr - image and video hosting website
Preact.js - Preact is a fast 3kB alternative to React with the same modern API. Components & Virtual DOM.
digiKam - Professional Photo Management with the Power of Open Source
w2ui - W2UI is a small JavaScript UI library with a complete set of widgets: layout, grid, sidebar, toolbar, tabs, fields, popup, utilities.