# SvelteKit 3.0.0-next.21

- Product: SvelteKit (https://whatsnew.fyi/product/sveltekit)
- Vendor: Svelte
- Date: 2026-08-12
- Version: 3.0.0-next.21
- Original notes: https://github.com/sveltejs/kit/releases/tag/%40sveltejs/kit%403.0.0-next.21
- Permalink: https://whatsnew.fyi/product/sveltekit/releases/3.0.0-next.21
- Labels: Pre-release

What's New is an index, not a publisher: every entry below links to the vendor's own release notes, which are the authoritative source. Entries are labelled where they are hand-curated sample data, pre-releases, or drawn from a secondary source such as a developer blog.

Reuse: the summaries, labels and curation here are © What's New. Quote freely with attribution and a link back; wholesale republication of the corpus is not permitted — terms: https://whatsnew.fyi/terms. The vendors' own release notes remain their publishers'.

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- **removed** — move remote function types and isValidationError to @sveltejs/kit/remote
- **removed** — move RequestEvent and Cookies to $app/server
- **fixed** — correctly implement Vite plugin hook filters
- **fixed** — yield to allow prerender updates to be visible
- **fixed** — don't destroy partial-line app output with the prerender progress line

###### Major Changes

- breaking: move remote function types and `isValidationError` to `@sveltejs/kit/remote` ([#16764](https://github.com/sveltejs/kit/pull/16764))

- breaking: move `RequestEvent` and `Cookies` to `$app/server` ([#16751](https://github.com/sveltejs/kit/pull/16751))

###### Patch Changes

- fix: correctly implement Vite plugin hook filters ([#16760](https://github.com/sveltejs/kit/pull/16760))

- fix: yield to allow prerender updates to be visible ([#16748](https://github.com/sveltejs/kit/pull/16748))

- fix: don't destroy partial-line app output with the prerender progress line ([#16750](https://github.com/sveltejs/kit/pull/16750))