[vite-plugin] Support auxiliary Workers with new config

[ericclemmons]

Adds auxiliary Worker support when experimental.newConfig is enabled. Existing auxiliaryWorkers[].configPath entries now point to each auxiliary Worker's TypeScript config, while legacy Wrangler config behavior remains unchanged when the experiment is disabled.

The auxiliary configs use the same @cloudflare/config conversion path as the entry Worker, participate in config dependency watching, and retain parsed config data for Build Output API emission.

This is to maiintain parity with https://developers.cloudflare.com/workers/local-development/multi-workers/#single-dev-command. My preference is instead having something like this:

import * as api from "@repo/api" with { type: "cf-worker" }

...
env: {
  API: bindings.worker(api)
}

But that's just an incremental step to eventually having defineProject(...)!

---

• Tests
  • Tests included/updated
  • Automated tests not possible - manual testing has been completed as follows:
  • Additional testing not necessary because:
• Public documentation
  • Cloudflare docs PR(s):
  • Documentation not necessary because: this extends an experimental API and includes a changeset plus an executable playground example.

A picture of a cute animal (not mandatory, but encouraged)

---

[changeset-bot]

🦋 Changeset detected

Latest commit: a2c8c54

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

This PR includes changesets to release 1 package

Name	Type
@cloudflare/vite-plugin	Minor

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[workers-devprod]

Codeowners approval required for this PR:

• @cloudflare/wrangler

Show detailed file reviewers

• .changeset/quiet-pears-help.md: [@cloudflare/wrangler]
• packages/vite-plugin-cloudflare/playground/experimental-config/tests/worker.spec.ts: [@cloudflare/wrangler]
• packages/vite-plugin-cloudflare/playground/experimental-config/auxiliary/cloudflare.config.ts: [@cloudflare/wrangler]
• packages/vite-plugin-cloudflare/playground/experimental-config/auxiliary/index.ts: [@cloudflare/wrangler]
• packages/vite-plugin-cloudflare/playground/experimental-config/cloudflare.config.ts: [@cloudflare/wrangler]
• packages/vite-plugin-cloudflare/playground/experimental-config/src/index.ts: [@cloudflare/wrangler]
• packages/vite-plugin-cloudflare/playground/experimental-config/vite.config.ts: [@cloudflare/wrangler]
• packages/vite-plugin-cloudflare/src/tests/experimental-new-config.spec.ts: [@cloudflare/wrangler]
• packages/vite-plugin-cloudflare/src/plugin-config.ts: [@cloudflare/wrangler]

[github-actions]

⚠️ Issues found

.changeset/quiet-pears-help.md

• The changeset describes a feature behind experimental.newConfig but does not include an explicit note on how users can opt into the experimental feature. Please add a sentence explaining how to enable experimental.newConfig (e.g., where to set the flag / config option).

[ask-bonk]

I'm Bonk, and I've done a quick review of your PR.

Summary: enables auxiliaryWorkers[].configPath to point at a per-Worker cloudflare.config.ts when experimental.newConfig is on, routing auxiliary configs through the same @cloudflare/config conversion + watch + Build-Output path as the entry Worker.

One actionable issue (medium): relative string entrypoints in an auxiliary config are resolved against the project root instead of the auxiliary config's own directory. Everything else looks consistent with the legacy path.

[ask-bonk]

Review posted successfully to PR #14654.

I reviewed PR #14654 ([vite-plugin] Support auxiliary Workers with new config) and posted a batch review with one actionable finding:

Medium — relative string entrypoints in auxiliary configs resolve against the wrong base directory. The new-config auxiliary path forces configPath: undefined into resolveWorkerConfig, so maybeResolveMain falls back to root when resolving a relative main. The playground avoids this only because it uses the cf-worker import attribute (which @cloudflare/config converts to an absolute path). A plain-string entrypoint: "./index.ts" in a subdirectory auxiliary config passes through verbatim and would resolve to <root>/index.ts instead of the config-relative location. I posted a suggestion to anchor resolution to the auxiliary config's directory.

Everything else (validation guards, configPaths watch wiring, parsedNewConfig plumbing, generateTypes: false for aux, error display names, changeset) is consistent with the existing legacy path.

github run

[pkg-pr-new]

@cloudflare/autoconfig

npm i https://pkg.pr.new/@cloudflare/autoconfig@14654

create-cloudflare

npm i https://pkg.pr.new/create-cloudflare@14654

@cloudflare/deploy-helpers

npm i https://pkg.pr.new/@cloudflare/deploy-helpers@14654

@cloudflare/kv-asset-handler

npm i https://pkg.pr.new/@cloudflare/kv-asset-handler@14654

miniflare

npm i https://pkg.pr.new/miniflare@14654

@cloudflare/pages-shared

npm i https://pkg.pr.new/@cloudflare/pages-shared@14654

@cloudflare/unenv-preset

npm i https://pkg.pr.new/@cloudflare/unenv-preset@14654

@cloudflare/vite-plugin

npm i https://pkg.pr.new/@cloudflare/vite-plugin@14654

@cloudflare/vitest-pool-workers

npm i https://pkg.pr.new/@cloudflare/vitest-pool-workers@14654

@cloudflare/workers-auth

npm i https://pkg.pr.new/@cloudflare/workers-auth@14654

@cloudflare/workers-editor-shared

npm i https://pkg.pr.new/@cloudflare/workers-editor-shared@14654

@cloudflare/workers-utils

npm i https://pkg.pr.new/@cloudflare/workers-utils@14654

wrangler

npm i https://pkg.pr.new/wrangler@14654

commit: a2c8c54

[devin-ai-integration]

Devin Review found 1 potential issue.

View 1 additional finding in Devin Review.