alien-dom

Component engine that feels like React but has…

• Transparent observables (implicit reactivity, components are observers)
  • No need to explicitly wrap your components (see MobX)
  • No need for weird foo() access patterns (see Solid.js)
  • Host elements (i.e. div) accept observable refs as props!
• Synchronous top-down JSX evaluation (requires a compile step)
  • …so stack traces aren't useless!
  • …and you get DOM elements immediately! (no virtual DOM, thanks to morphdom)
• Automatically memoized functions and inline objects
• Automatic disposal of effects and event listeners (write less manual cleanup in useEffect destructors)
• Strongly typed event channels (see defineChannel)
• Nested components just work ™️
• Built-in niceties
  • Flexible class prop (supports arrays and objects)
  • Light-weight spring animations
  • Light-weight observability engine
  • jQuery-inspired DOM extensions (optional)
  • A standard library of component hooks (tree-shakeable)
  • Easy context forwarding

How exactly does it "feel like React?"

The look and feel of React is preserved, including:

• Plain function components (but no component classes)
• Good ol' JSX (i.e. <div class="foo" key={index} />) albeit with different evaluation semantics
• Component hooks with similar names (i.e. useEffect, useMemo, useRef, useState) albeit with different behavior (except for useEffect)
• The rules of React hooks apply to Alien DOM hooks (i.e. hooks must be called at the top level of a component) but event listeners can be attached anywhere

Are there missing features?

As this library is in beta, there are drawbacks compared to React:

• No error boundaries (yet)
• No suspense (yet)
• No server-side rendering (yet)
• No plugin for Vite (yet)
• No concurrent mode (probably never)

I'm ready to learn more!

• See the Getting Started page for a quick introduction.
• See the Quirks page for things to keep in mind.

Credits

These libraries contribute a ton to Alien DOM's functionality:

• we forked the awesome jsx-dom package
• we forked the sublime morphdom package