Some background: svelte.config.js was originally created so the VS Code extension knows about the compiler options and - more crucially - the preprocessors.
They were very common back then because you e.g. had to use one to get Typescript support in Svelte. Nowadays
Simon H
Say goodbye to svelte.config.js - you don't need it anymore!
The newest version of SvelteKit allows you to configure everything via its Vite plugin, and VS Code, svelte-check and SvelteKit itself can all read from it.
On file less cluttering your project root.
