--- meta: title: useIsomorphicLayout | React Spring 'og:title': useIsomorphicLayout | React Spring 'twitter:title': useIsomorphicLayout | React Spring description: API documentation for the useIsomorphicLayout utility hook in React Spring. 'og:description': API documentation for the useIsomorphicLayout utility hook in React Spring. 'twitter:description': API documentation for the useIsomorphicLayout utility hook in React Spring. 'og:url': https://www.react-spring.dev/docs/utilities/use-isomorphic-layout-effect 'twitter:url': https://www.react-spring.dev/docs/utilities/use-isomorphic-layout-effect sidebar_position: 1 --- import { formatFrontmatterToRemixMeta } from '../helpers/meta' export const meta = formatFrontmatterToRemixMeta(frontmatter) # useIsomorphicLayoutEffect ## Usage ```tsx lines=1,9-20 import { animated, useSpring, useIsomorphicLayoutEffect } from '@react-spring/web' const MyComponent = ({position}) => { const [springs, api] = useSpring(() => { y: 0, x: 0, }, []) useIsomorphicLayoutEffect(() => { api.start({ from: { x: 0, y: 0, }, to: { x: position.x, y: position.y, } }) },[position]) return } ``` ## Why do we need this? When we want to perform side-effects caused by rendering a component we need to use [`useEffect`](https://reactjs.org/docs/hooks-reference.html#useeffect) or [`useLayoutEffect`](https://reactjs.org/docs/hooks-reference.html#uselayouteffect). Now, the latter, `useLayoutEffect` in our opinion, is better for animations because it renders "before the browser has a chance to paint", therefore if you want to prepare a node e.g. a div for animation before actually animating it, it's probably better to ensure no paint happens, otherwise you might get a sort of UI tear where the item suddenly jumps to a new position. Neither of the above effect hooks run on the server, however, `useLayoutEffect` causes react warnings when server-side rendering your pages (if you're using nextjs for example). So it encourages you to move the code to `useEffect`. However, as we described above this isn't best for animations. ## What does it do? This is where our `useIsomorphicLayoutEffect` utility hook comes in. By performing a simple (yet robust) check, the hook correctly returns `useEffect` for server-side environments and `useLayoutEffect` for client-side environments, thus the best of both worlds in this case. ## Typescript The type signature will be identical to the signatures of `useEffect` and `useLayoutEffect` installed in your project, but just to save you time, it's here below: ```ts function useIsomorphicLayoutEffect(effect: () => (void | () => void), deps?: ReadonlyArray) ```