Small, fast, awesome. The only ES5-ish set of polyfills (shims) you can mix-and-match because they're individual AMD modules.
Object.observe polyfill/shim trying to be compliant
Date() for humans
Tiny polyfill for the placeholder form element attribute. Requires Prototype.js.
⏰ Day.js 2KB immutable date library alternative to Moment.js with the same modern API
A lightweight engine that allows you to hitch new capabilities to the browser (prollyfill).
Tired of adding prefix for each broswer when it comes to the new css3 attributes?
This script is the defacto way to enable use of HTML5 sectioning elements in legacy Internet Explorer.