Use .onMount() to run logic once, immediately after the component renders for the first time. Unlike .effect(), it does not re-run on state changes — making it the right place for one-time setup work.
The callback receives the full component context, so you have direct access to state and derived. This makes .onMount() ideal for seeding initial data: fetch a resource, resolve its result, and write it into state — Ilha will re-render automatically once the data arrives.
Similar concepts
- React:
useEffectwith an empty dependency array - Vue:
onMounted() - Svelte:
onMount()