chore: configure the server runtime in one place

[Nic-Polumeyv]

Kit sets up its server runtime in six places: Server.init, prerender, analyse, dev, preview and the fallback generator. Each calls a different subset of the same module-level setters by hand, in an order four comments explain. The Server class itself holds no state since #16967, its constructor is set_manifest.

configure in the generated server module now owns that order, and init and respond replace the class. The server object adapters get from generateServerInstance is unchanged and still only accepts env and read, so the internal options configure takes (building, prerendering, manifest) are not reachable through it. Server stays as a deprecated shim.

[pkg-svelte-dev]

Install the latest version of @sveltejs/kit from c440ed4:

pnpm add https://pkg.svelte.dev/@sveltejs/kit/c/c440ed4d09147d080bad8db59310929aba65a3c5

Open in pkg.svelte.dev: https://pkg.svelte.dev/repos/kit/pr/17000

[changeset-bot]

🦋 Changeset detected

Latest commit: c440ed4

The changes in this PR will be included in the next version bump.

This PR includes changesets to release 1 package

Name	Type
@sveltejs/kit	Patch

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[svelte-docs-bot]

Preview: https://svelte-dev-git-preview-kit-17000-svelte.vercel.app/

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📝 Walkthrough

Walkthrough

The server lifecycle now uses module-level configure, init, respond, and create_server APIs. Build, prerender, fallback, analysis, development, preview, generated modules, type declarations, and migration documentation use the new API surface.

Changes

Server lifecycle migration

Layer / File(s)	Summary
Server contracts and generated configuration	Server module types define configure, init, respond, and create_server. The generated module applies runtime options and adapts read results to runtime streams.
Runtime lifecycle and request handling	The runtime provides shared initialization and response functions. create_server returns bound handlers, while Server delegates to the new implementation.
Build and postbuild server integration	Build and postbuild paths configure and initialize the module-level server, then call respond for requests.
Vite adapter integration and instrumentation	Development, preview, and test instrumentation paths use the exported lifecycle functions instead of constructing Server instances. The changeset and migration documentation describe the deprecated Server class.

Sequence Diagram(s)

sequenceDiagram
  participant ViteAdapter
  participant GeneratedServer
  participant RuntimeServer
  ViteAdapter->>GeneratedServer: init manifest, environment, assets, and read
  GeneratedServer->>RuntimeServer: configure runtime state
  ViteAdapter->>GeneratedServer: respond request
  GeneratedServer->>RuntimeServer: respond request

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Merge Risk: ⚪ Minimal · up to c440e

This change centralizes server lifecycle setup and updates generated server creation to use the new factory API. No concrete current-head behavior, compatibility, or deployment risk remains identified.

🚥 Pre-merge checks | ✅ 2

✅ Passed checks (2 passed)

Check name	Status	Explanation
Title check	✅ Passed	The title uses the required chore: prefix and accurately describes the central server runtime configuration change.
Backward Compatibility Impact Disclosure	✅ Passed	No breaking public interface change is introduced by this PR. The public @sveltejs/kit Server interface and ServerInitOptions are unchanged, and Server remains exported as a deprecated compati…

Full details: Backward Compatibility Impact Disclosure

Explanation

No breaking public interface change is introduced by this PR. The public @sveltejs/kit Server interface and ServerInitOptions are unchanged, and Server remains exported as a deprecated compatibility shim. Builder.generateServerInstance still produces a server object with init and respond; the removed setter exports are from the generated internal server module, which is not a package export. No public request/response fields, defaults, or config keys changed. The patch changeset is therefore sufficient.

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[elliott-with-the-longest-name-on-github]

Looks good, just one nit to look at before we merge