lit-element

lit-element is a lightweight base class for creating fast, reusable web components using standard Web Components APIs. It is part of the Lit library (formerly Polymer) developed by Google and provides a simple, declarative way to build custom elements with reactive properties. lit-element uses tagged template literals for rendering and includes efficient DOM updating through the lit-html rendering library. Components created with lit-element are framework-agnostic and can be used with any JavaScript framework or vanilla JavaScript. The library emphasizes small bundle sizes, with a base class of only about 5KB. lit-element supports TypeScript decorators, reactive properties, scoped CSS, and lifecycle callbacks. It is particularly popular for design system components and reusable UI libraries that need to work across different technology stacks.