SvelteKit is a framework for building high-performance web apps that can handle things like build optimizations, offline support, prefetching pages, and configurable rendering. 

It combines Vite with the Svelte plugin to provide a feature-rich developer experience and uses Hot Module Replacement (HMR) to have developers see their changes to the code reflected in the browser.

Each page of the app is a component of Svelte, which is a UI framework that compiles components to optimize vanilla Java that also took the top spot as the most loved framework in a Stack Overflow survey. Developers can also create projects by adding files to the src/routes directory of a project which will be server-rendered to improve app speed.

“Unlike single-page apps, SvelteKit doesn’t compromise on SEO, progressive enhancement or the initial load experience — but unlike traditional server-rendered apps, navigation is instantaneous for that app-like feel,” the project’s website, which contains additional details states.

SvelteKit, which is still in early development, uses “fetch” for getting data from a network and the Fetch API includes the interfaces Request, which contains useful methods like ‘request.json()’ and ‘request.formData()’ for getting data that was posted to an endpoint, an instance of Response, and the Headers interface to read incoming ‘request.headers’ and set outgoing ‘response.headers.’ The project also uses Stream, URL, and Web Crypto APIs.