Mithril

 Mithril is a client-side JavaScript framework that is used primarily in developing the Single Page Applications. As there are no derived functions from a base class, the implementation of the framework is more straightforward. It's small (< 8kb gzip), fast and provides routing and XHR utilities out of the box. It has a few features similar to React.

Key Features:

• Built-in Utilities: Unlike many other small frameworks, it includes routing and XHR (HTTP requests) utilities out of the box, reducing the need for external libraries.

• Virtual DOM: It uses a high-performance Virtual DOM implementation to efficiently update the UI.

• Small API Surface: Its API is minimal and relies heavily on plain JavaScript, leading to a shallow learning curve for those familiar with the language.

• No Build Tool Required: While it supports JSX (via Babel), it is idiomatic to write views using Hyperscript (m() functions), which allows you to build applications without a complex build pipeline.

Use Cases and Adoption:

Performance-Critical Apps: Due to its speed and small footprint, it is used by platforms like Lichess (a popular open-source chess server). 

Enterprise Use: Companies such as Vimeo and Nike have utilized it in their tech stacks. 

Browser Support: It supports modern browsers and remains compatible back to IE11 without requiring polyfills.

Getting Started:

You can install it via npm or use a CDN for quick prototyping: 

NPM: npm install mithril --save

CDN: unpkg.com/mithril or jsdelivr.net/npm/mithril 

Playground: Test the framework instantly at flems.io/mithril.

Official Mithril.js website.

Source:

- https://mithril.js.org/

- Google search

- https://news.ycombinator.com/item?id=43550317

- https://www.numendo.com/blog/framework/mithril-js/