Svelte · Junior · Question 12 of 76

What does `$effect` do?

✓Correct answer: Runs code after the component is mounted and again whenever the state it read changes
2Runs code once on the server before rendering
3Declares derived state

Explanation

Effects are for side effects: working with canvas, third-party libraries, subscriptions. They run in the browser only, not during SSR.

Further reading

Svelte: $effect ↗

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