chore: avoid double-bundling by teemingc · Pull Request #17068 · sveltejs/kit

teemingc · 2026-09-08T17:15:40Z

stacked on top of #17077

This PR gets rid of the second bundle step in the Node adapter in favour of configuring the Vite build.

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pkg-svelte-dev · 2026-09-08T17:15:43Z

Install the latest version of @sveltejs/kit from d4d3267:

pnpm add https://pkg.svelte.dev/@sveltejs/kit/c/d4d3267b77a505cf6dca5b209e615c23b5616b9f

Open in pkg.svelte.dev: https://pkg.svelte.dev/repos/kit/pr/17068

changeset-bot · 2026-09-08T17:15:46Z

🦋 Changeset detected

Latest commit: d4d3267

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

This PR includes changesets to release 1 package

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@sveltejs/adapter-node	Patch

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teemingc · 2026-09-08T17:16:27Z

+								return {
+									environments: {
+										ssr: {
+											// TODO: replace build-time constants in the adapter's own entrypoints only, so that identifiers in the app or its dependencies aren't accidentally replaced


need to figure out how to apply the defines only to our own entrypoints. probably by adding a transform hook again rather than using defines here?

teemingc · 2026-09-08T17:16:40Z

+													// pass means shared modules (e.g. `SvelteKitError` from `@sveltejs/kit`)
+													// aren't duplicated. See https://github.com/sveltejs/kit/issues/15755
+													input: {
+														// TODO: adapter-index.js should be index.js but we need to avoid overridding the sveltekit one


need to resolve this so that we can run node build rather than node build/adapter-index.js

svelte-docs-bot · 2026-09-08T17:18:24Z

Preview: https://svelte-dev-git-preview-kit-17068-svelte.vercel.app/

Co-authored-by: Copilot App <223556219+Copilot@users.noreply.github.com>

Rich-Harris · 2026-09-08T20:22:05Z

(oops, approved while platform-tests are still red. still, looks good apart from whatever's causing those)

teemingc · 2026-09-09T02:35:32Z

I have some of those fixes locally so I’ll push those up soon

EDIT: pushed

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…endency

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…e-double-bundle

implementation has changed

…emingc-adapter-regression-tests-version-3

…e-double-bundle

Co-authored-by: Copilot App <223556219+Copilot@users.noreply.github.com>

…endency

…emingc-adapter-regression-tests-version-3

…e-double-bundle

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

well this is cool

elliott-with-the-longest-name-on-github · 2026-09-09T21:43:04Z

 				written.map((file) => extname(file)).filter((ext) => ext && !compressed_extensions.has(ext))
 			);

-			builder.log.minor('Building server');


did we intentionally lose this log?

Yeah I didn’t think we needed it now that we have no second bundling step. At least I don’t think we log this for other adapters (maybe because they have “generating serverless function” instead 🤔)

stacked on #17068 closes #10040 Adapter builders can copy generated sourcemaps to a different directory, leaving relative source paths pointing at the wrong path. This PR rebases relative `sources` and `sourceRoot` values during copies while preserving absolute paths, URLs, mappings, indexed-map structure, and unchanged map text when no rewrite is needed. An alternative is to use the Rolldown `sourcemapPathTransform` hook but that makes them invalid for vite preview https://rolldown.rs/reference/OutputOptions.sourcemapPathTransform --- ### Please don't delete this checklist! Before submitting the PR, please make sure you do the following: - [x] It's really useful if your PR references an issue where it is discussed ahead of time. In many cases, features are absent for a reason. For large changes, please create an RFC: https://github.com/sveltejs/rfcs - [x] This message body should clearly illustrate what problems it solves. - [x] Ideally, include a test that fails without this PR but passes with it. ### Tests - [ ] Run the tests with `pnpm test` and lint the project with `pnpm lint` and `pnpm check` ### Changesets - [x] If your PR makes a change that should be noted in one or more packages' changelogs, generate a changeset by running `pnpm changeset` and following the prompts. Changesets that add features should be `minor` and those that fix bugs should be `patch`. Please prefix changeset messages with `feat:`, `fix:`, or `chore:`. ### Edits - [x] Please ensure that 'Allow edits from maintainers' is checked. PRs without this option may be closed. --------- Co-authored-by: Copilot App <223556219+Copilot@users.noreply.github.com> Co-authored-by: vercel[bot] <35613825+vercel[bot]@users.noreply.github.com> Co-authored-by: Vercel <vercel[bot]@users.noreply.github.com>

…17103) #17068 injects the values `adapt` learns after the Vite build by regex-patching stub identifiers in the built chunks and remapping their sourcemaps. Now `adapt` writes them to `build/adapter-node.js` and the chunks import it. No chunk is edited after Vite writes it, and the adapter has no runtime dependencies.

wip

0cb1ab9

teemingc added the pkg:adapter-node label Sep 8, 2026

teemingc added the needs-platform-tests This PR needs to run platform tests in order to merge. label Sep 8, 2026

teemingc commented Sep 8, 2026

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teemingc and others added 2 commits September 9, 2026 01:51

test: verify adapter-node externalizes dependencies

feba543

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test: move adapter-node build assertion to vitest

7c7bf0d

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Rich-Harris previously approved these changes Sep 8, 2026

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teemingc and others added 9 commits September 9, 2026 21:16

test: build adapter-node before app tests

0fb6e41

Co-authored-by: Copilot App <223556219+Copilot@users.noreply.github.com>

fix: resolve adapter-node bundling TODOs

6264543

Co-authored-by: Copilot App <223556219+Copilot@users.noreply.github.com>

refactor: preserve adapter transform source maps

3c89908

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fix: preserve maps when replacing adapter stubs

56d02e4

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chore: update magic-string

84aca89

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test: clarify adapter identifier coverage

5ea1231

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refactor: separate adapter and server output

88e9df2

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refactor: expose adapter as root index

f55e2dc

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refactor: move regression coverage to follow-up

7699c87

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teemingc mentioned this pull request Sep 9, 2026

test: add adapter bundling regressions #17075

Closed

6 tasks done

teemingc added this pull request to stack #17076 September 9, 2026 14:01

teemingc removed this pull request from stack #17076 September 9, 2026 14:04

teemingc and others added 3 commits September 9, 2026 22:07

Merge branch 'version-3' into teemingc-test-adapter-node-external-dep…

1e030f7

…endency

Merge branch 'version-3' into remove-double-bundle

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test: add adapter bundling regressions

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teemingc mentioned this pull request Sep 9, 2026

test: verify handler is exported #17077

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test: verify handler export

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teemingc added 2 commits September 9, 2026 22:32

Merge branch 'version-3' into remove-double-bundle

eece9dc

Merge branch 'teemingc-adapter-regression-tests-version-3' into remov…

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…e-double-bundle

teemingc marked this pull request as ready for review September 9, 2026 14:43

teemingc requested a review from Rich-Harris September 9, 2026 14:43

vercel Bot reviewed Sep 9, 2026

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Comment thread packages/adapter-node/index.js Outdated

Comment thread packages/adapter-node/index.js

teemingc added 3 commits September 9, 2026 23:00

use composable filters

3962962

Update index.js

a7f63a3

Update index.js

e5da82e

teemingc changed the base branch from version-3 to teemingc-adapter-regression-tests-version-3 September 9, 2026 15:12

teemingc and others added 3 commits September 9, 2026 23:13

Merge branch 'teemingc-test-adapter-node-external-dependency' into te…

80cbfc8

…emingc-adapter-regression-tests-version-3

Merge branch 'teemingc-adapter-regression-tests-version-3' into remov…

d2d908c

…e-double-bundle

refactor: locate adapter chunks from Vite manifest

eef6976

Co-authored-by: Copilot App <223556219+Copilot@users.noreply.github.com>

This was linked to issues Sep 9, 2026

make node adapter chunk names more descriptive #11064

Closed

adapter-node : sharp included in bundle #13464

Closed

teemingc added 3 commits September 10, 2026 01:52

Merge branch 'version-3' into teemingc-test-adapter-node-external-dep…

0f84abd

…endency

Merge branch 'teemingc-test-adapter-node-external-dependency' into te…

b778c61

…emingc-adapter-regression-tests-version-3

Merge branch 'teemingc-adapter-regression-tests-version-3' into remov…

d4d3267

…e-double-bundle

teemingc mentioned this pull request Sep 9, 2026

fix: rebase sourcemaps when copying files #17082

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5 of 6 tasks

elliott-with-the-longest-name-on-github approved these changes Sep 9, 2026

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Base automatically changed from teemingc-adapter-regression-tests-version-3 to version-3 September 9, 2026 22:21

elliott-with-the-longest-name-on-github merged commit 03f7b48 into version-3 Sep 9, 2026
70 of 71 checks passed

elliott-with-the-longest-name-on-github deleted the remove-double-bundle branch September 9, 2026 22:22

github-actions Bot mentioned this pull request Sep 9, 2026

Version Packages (next) #17062

Merged

Nic-Polumeyv mentioned this pull request Sep 13, 2026

chore: hand adapt-time values to the adapter-node server as a module #17103

Merged

Nic-Polumeyv mentioned this pull request Sep 16, 2026

breaking: bundle the adapter-bun server with the app's Vite build #17120

Merged

This was referenced Sep 25, 2026

fix(adapter-node): bundle SvelteKit when declared as a dependency #17207

Closed

fix: respect runtime export conditions in server adapters #17234

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chore: avoid double-bundling - #17068

chore: avoid double-bundling#17068
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