shim
shim.js is the a collection of UMD modules that shim (aka "polyfill") old environments to support modern (aka "ES5-ish" and "ES6-ish") javascript.
es5-shim
ECMAScript 5 compatibility shims for legacy JavaScript engines
es5-ext
ECMAScript extensions and shims
node-es5
A shim to always run node in es5 proper "strict mode"