Svelte - Cybernetically enhanced web apps
Glimmer - Fast and light-weight UI components for the web
Preact.js - Preact is a fast 3kB alternative to React with the same modern API. Components & Virtual DOM.
Inferno - An extremely fast React-like javascript library for building modern user interfaces.
Deku - Functional view library for building UI components as an alternative to React
Vue.js - Reactive Components for Modern Web Interfaces