JavaScript libraries
Polyfill io is a service which accepts a request for a set of browser features and returns only the polyfills that are needed by the requesting browser

JavaScript libraries
Touch enabled jQuery plugin that lets you create beautiful responsive carousel slider

Font scripts
Making the web more beautiful fast and open through great typography

Font scripts
Typekit is an online service which offers a subscription library of fonts

Analytics
Siteimprove is the go to software for data driven teams Optimize your content for everything from SEO and analytics to accessibility

Ecommerce
The World Wide Web Consortium W3C develops standards and guidelines to help everyone build a web based on the principles of accessibility internationalization privacy and security