Components, widgets, features

mountly has three things, and they are not synonyms. The vocabulary is enforced because it pays off the moment you have more than one widget on a page.

Component

Your normal React, Vue, or Svelte component. Whatever you’d write today. mountly never asks you to learn a new component model.

export default function SignupCard({ headline }: { headline: string }) {
  return <h2>{headline}</h2>;
}

A component is the input.

Widget

A component wrapped by a framework adapter into a self-contained, mountable, framework-agnostic unit. Every adapter exposes the same surface:

const widget = createWidget(Component, { styles });
// → { mount(container, props), unmount(container) }

A widget knows nothing about when it loads. It knows how to render into a container and how to clean itself up. It always mounts inside a shadow root, so styles are scoped both ways.

A widget is the framework-agnostic output.

Feature

A widget plus the on-demand lifecycle: a trigger, a module loader, optional data fetching, dual caching, and a state machine. This is what you actually attach to a page.

const feature = createOnDemandFeature({
  moduleId: "signup-card",
  loadModule: () => import("./signup-card.js"),
  render: ({ mod, container, props }) => mod.mount(container, props),
});

feature.attach({ trigger: el, preloadOn: "hover", activateOn: "click" });

A feature is a widget that knows when to show up.

Why enforce the vocabulary

Without it, “widget” and “feature” drift into synonyms and the docs lose their footing. With it, you can read a sentence like “the host registers two features that share a widget” and know exactly what’s true:

• One widget module is loaded.
• Two features wrap it, possibly with different triggers, props, or contexts.
• Two mounts can happen on the page; one cache hit covers both.

Don’t substitute the terms in code, in docs, or in PR descriptions.

A one-line summary

You write components, the adapter wraps them as widgets, and you ship them as features.

That’s the whole model.