2005 - Dojo
A JavaScript toolkit that saves you time and scales with your development process. Provides everything you need to build a Web app. Language utilities, UI components, and more, all in one place, designed to work together perfectly.
At the heart of Enyo is a simple but powerful encapsulation model, which helps you factor application functionality into self-contained building blocks that are easy to reuse and maintain. Each piece of an Enyo application is a Component, and Components are constructed out of other Components.
Elm is a domain-specific programming language for declaratively creating web browser-based graphical user interfaces. Elm is purely functional, and is developed with emphasis on usability, performance, and robustness. It advertises no runtime exceptions in practice, made possible by the Elm compiler's static type checking.
Polymer is an open-source JavaScript library for building web applications using Web Components. The library is being developed by Google developers and contributors on GitHub. Modern design principles are implemented as a separate project using Google's Material Design design principles.