# What changed in @sveltejs/adapter-node

> 22 changes in @sveltejs/adapter-node 5 to 6 from its official release notes, upgrade guides and advisories: 9 breaking, 1 security, 2 new APIs and options. Each one cited. Sources checked 2026-10-28. HTML: https://unstale.sh/npm/@sveltejs/adapter-node/

To see which of these apply to a repository, run `npx @unstale/cli init` in it.

## @sveltejs/adapter-node 6

### Breaking changes

- This builder API is replaced by builder.generateServerInstance and builder.manifest. (6.0.0) — [release notes](https://github.com/sveltejs/kit/releases/tag/%40sveltejs/adapter-node%406.0.0)
- A new builder API replaces builder.generateManifest. (6.0.0) — [release notes](https://github.com/sveltejs/kit/releases/tag/%40sveltejs/adapter-node%406.0.0)
- A new builder API replaces builder.generateManifest. (6.0.0) — [release notes](https://github.com/sveltejs/kit/releases/tag/%40sveltejs/adapter-node%406.0.0)
- The config option is removed. (6.0.0) — [release notes](https://github.com/sveltejs/kit/releases/tag/%40sveltejs/adapter-node%406.0.0)
- Static assets are recorded at build time and served from tables recorded at adapt time; files added to the output afterwards are not served. (6.0.0) — [release notes](https://github.com/sveltejs/kit/releases/tag/%40sveltejs/adapter-node%406.0.0)
- Static assets are validated with content-hash ETags, and Last-Modified is no longer sent. (6.0.0) — [release notes](https://github.com/sveltejs/kit/releases/tag/%40sveltejs/adapter-node%406.0.0)
- Static assets are served only for GET and HEAD requests. (6.0.0) — [release notes](https://github.com/sveltejs/kit/releases/tag/%40sveltejs/adapter-node%406.0.0)
- SvelteKit 3 is now required. (6.0.0) — [release notes](https://github.com/sveltejs/kit/releases/tag/%40sveltejs/adapter-node%406.0.0)
- Vite ^8.0.12 is now required. (6.0.0) — [release notes](https://github.com/sveltejs/kit/releases/tag/%40sveltejs/adapter-node%406.0.0)

### New APIs and options

- A new response option aborts request.signal when the response closes prematurely. (6.0.0) — [release notes](https://github.com/sveltejs/kit/releases/tag/%40sveltejs/adapter-node%406.0.0)
- A new config option provides the origin setting. (6.0.0) — [release notes](https://github.com/sveltejs/kit/releases/tag/%40sveltejs/adapter-node%406.0.0)

### Behavior and default changes

- Environment variables are populated before instrumentation.server.js is evaluated. (6.0.0) — [release notes](https://github.com/sveltejs/kit/releases/tag/%40sveltejs/adapter-node%406.0.0)

### Fixes and other changes

- The adapter instrumentation API is updated. (6.0.0) — [release notes](https://github.com/sveltejs/kit/releases/tag/%40sveltejs/adapter-node%406.0.0)
- Static files are served with the Content-Type recorded in the manifest. (6.0.0) — [release notes](https://github.com/sveltejs/kit/releases/tag/%40sveltejs/adapter-node%406.0.0)
- Scheme-like path segments no longer cause off-site trailing-slash redirects. (6.0.0) — [release notes](https://github.com/sveltejs/kit/releases/tag/%40sveltejs/adapter-node%406.0.0)
- Redirects are relative to preserve stripped path prefixes. (6.0.0) — [release notes](https://github.com/sveltejs/kit/releases/tag/%40sveltejs/adapter-node%406.0.0)

## @sveltejs/adapter-node 5

### Security

- SvelteKit is vulnerable to denial of service and possible SSRF when using prerendering (5.5.1) — [security advisory](https://github.com/advisories/GHSA-J62C-4X62-9R35)

### Fixes and other changes

- Deletes an existing socket file on startup. (5.5.7) — [release notes](https://github.com/sveltejs/kit/releases/tag/%40sveltejs/adapter-node%405.5.7)
- Adds the X-Accel-Buffering: no header to text/event-stream responses to prevent reverse proxies such as nginx from buffering streamed responses. (5.5.7) — [release notes](https://github.com/sveltejs/kit/releases/tag/%40sveltejs/adapter-node%405.5.7)
- Ensures ENV_PREFIX is defined. (5.5.6) — [release notes](https://github.com/sveltejs/kit/releases/tag/%40sveltejs/adapter-node%405.5.6)
- Correctly resolves the root directory on the server. (5.5.6) — [release notes](https://github.com/sveltejs/kit/releases/tag/%40sveltejs/adapter-node%405.5.6)
- Avoids a circular dependency between server initialisation and hook retrieval that caused the app to crash on start. (5.5.6) — [release notes](https://github.com/sveltejs/kit/releases/tag/%40sveltejs/adapter-node%405.5.6)