solidjs/solid

Solid is a JavaScript/TypeScript library for building user interfaces on the web. The problem it addresses is performance: most popular UI libraries (like React) use a virtual DOM, an in-memory copy of the interface that gets compared to the real browser DOM every time data changes, with only the differences applied. This comparison process has overhead. Solid takes a different approach: it compiles JSX templates directly into real DOM nodes at build time, and then uses fine-grained reactivity to update only the specific parts of the page that actually depend on changed data, without any virtual DOM comparison step. The core primitive in Solid is the signal, a small reactive value that, when it changes, automatically updates only the expressions that use it. Components in Solid run exactly once (not on every re-render like in React) and establish reactive subscriptions during that single run. Updates happen at the signal level, targeting only the affected DOM nodes directly. The result is very high rendering performance and a small library size, while keeping an API that should feel familiar to React developers (JSX syntax, component functions, hooks-like composables). Solid also supports server-side rendering, code splitting, and a full routing solution. A web developer who wants the familiar JSX-based component model but needs better runtime performance than React, or who wants to understand fine-grained reactivity as an architectural pattern, would use Solid. It is written in TypeScript, works in any modern browser, and is installed via npm.