Replace jQuery or MooTools with a <4kB Library
A client-side solution to conditional loading.
Layout elements in a grid, like a mason fitting stones in a wall
Highly customizable vanilla JS tooltip/popover library
NodeList implementation/library - Use the Native DOM APIs as easily as jQuery
DIY Presentation Micro-Framework
Motionia is a lightweight simplified on demand animation library! https://git.io/motionia
Scriptable Headless WebKit
Injects CSS into the document (it's a perfectly legal procedure)
Eliminates layout thrashing by batching DOM read/write operations
Accessible W3C conform accordion written in ES6.
bin-packing layout library
Waypoints is a small jQuery plugin that makes it easy to execute a function whenever you scroll to an element.
React components for efficiently rendering large lists and tabular data
MagJS - Modular Application Glue