Add warning to Wrangler if using the Bun runtime and an error is encountered

[penalosa]

Fixes https://jira.cfdata.org/browse/DEVX-1621

Add warning to Wrangler if using the Bun runtime and an error is encountered. Bun is not supported by Wrangler or Miniflare.

---

• Tests
  • TODO (before merge)
  • Tests included
  • Tests not necessary because:
• Wrangler / Vite E2E Tests CI Job required? (Use "e2e" label or ask maintainer to run separately)
  • I don't know
  • Required
  • Not required because: covered by unit tests
• Public documentation
  • TODO (before merge)
  • Cloudflare docs PR(s):
  • Documentation not necessary because: Already addressed in Remove mentions of Bun cloudflare-docs#19813
• Wrangler V3 Backport
  • TODO (before merge)
  • Wrangler PR: V3 Backport [#8889]: Add warning to Wrangler if using the Bun runtime and an error is encountered #8955
  • Not necessary because:

[changeset-bot]

🦋 Changeset detected

Latest commit: 2857e97

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

This PR includes changesets to release 2 packages

Name	Type
wrangler	Patch
@cloudflare/vitest-pool-workers	Patch

Not sure what this means? Click here to learn what changesets are.

Click here if you're a maintainer who wants to add another changeset to this PR

[github-actions]

A wrangler prerelease is available for testing. You can install this latest build in your project with:

npm install --save-dev https://prerelease-registry.devprod.cloudflare.dev/workers-sdk/runs/14406546365/npm-package-wrangler-8889

You can reference the automatically updated head of this PR with:

npm install --save-dev https://prerelease-registry.devprod.cloudflare.dev/workers-sdk/prs/8889/npm-package-wrangler-8889

Or you can use npx with this latest build directly:

npx https://prerelease-registry.devprod.cloudflare.dev/workers-sdk/runs/14406546365/npm-package-wrangler-8889 dev path/to/script.js

Additional artifacts:

cloudflare-workers-bindings-extension:

wget https://prerelease-registry.devprod.cloudflare.dev/workers-sdk/runs/14406546365/npm-package-cloudflare-workers-bindings-extension-8889 -O ./cloudflare-workers-bindings-extension.0.0.0-v865eff3a5.vsix && code --install-extension ./cloudflare-workers-bindings-extension.0.0.0-v865eff3a5.vsix

create-cloudflare:

npx https://prerelease-registry.devprod.cloudflare.dev/workers-sdk/runs/14406546365/npm-package-create-cloudflare-8889 --no-auto-update

@cloudflare/kv-asset-handler:

npm install https://prerelease-registry.devprod.cloudflare.dev/workers-sdk/runs/14406546365/npm-package-cloudflare-kv-asset-handler-8889

miniflare:

npm install https://prerelease-registry.devprod.cloudflare.dev/workers-sdk/runs/14406546365/npm-package-miniflare-8889

@cloudflare/pages-shared:

npm install https://prerelease-registry.devprod.cloudflare.dev/workers-sdk/runs/14406546365/npm-package-cloudflare-pages-shared-8889

@cloudflare/unenv-preset:

npm install https://prerelease-registry.devprod.cloudflare.dev/workers-sdk/runs/14406546365/npm-package-cloudflare-unenv-preset-8889

@cloudflare/vite-plugin:

npm install https://prerelease-registry.devprod.cloudflare.dev/workers-sdk/runs/14406546365/npm-package-cloudflare-vite-plugin-8889

@cloudflare/vitest-pool-workers:

npm install https://prerelease-registry.devprod.cloudflare.dev/workers-sdk/runs/14406546365/npm-package-cloudflare-vitest-pool-workers-8889

@cloudflare/workers-editor-shared:

npm install https://prerelease-registry.devprod.cloudflare.dev/workers-sdk/runs/14406546365/npm-package-cloudflare-workers-editor-shared-8889

@cloudflare/workers-shared:

npm install https://prerelease-registry.devprod.cloudflare.dev/workers-sdk/runs/14406546365/npm-package-cloudflare-workers-shared-8889

@cloudflare/workflows-shared:

npm install https://prerelease-registry.devprod.cloudflare.dev/workers-sdk/runs/14406546365/npm-package-cloudflare-workflows-shared-8889

Note that these links will no longer work once the GitHub Actions artifact expires.

---

[email protected] includes the following runtime dependencies:

Package	Constraint	Resolved
miniflare	workspace:*	4.20250409.0
workerd	1.20250409.0	1.20250409.0
workerd --version	1.20250409.0	2025-04-09

Please ensure constraints are pinned, and miniflare/workerd minor versions match.

[mlafeldt]

I've been using wrangler with bun for over a year without any problem. What's not working for you? (the linked Jira ticket requires logging in)

[github-actions]

These changes have been automatically backported to Wrangler v3 🎉 You can view the automatically updated PR at v3-maintenance...v3-maintenance-8889. Please check that PR for correctness, and make sure it's merged after this one. Thank you for helping us keep Wrangler v3 supported!

[github-actions]

A Wrangler prerelease is available for testing. You can install this latest build in your project with:

npm install --save-dev https://prerelease-registry.devprod.cloudflare.dev/workers-sdk/runs/14468730355/npm-package-wrangler-8889

Prereleases for other packages:

cloudflare-workers-bindings-extension:

wget https://prerelease-registry.devprod.cloudflare.dev/workers-sdk/runs/14468730355/npm-package-cloudflare-workers-bindings-extension-8889 -O ./cloudflare-workers-bindings-extension.0.0.0-vf2415fa5c.vsix && code --install-extension ./cloudflare-workers-bindings-extension.0.0.0-vf2415fa5c.vsix

create-cloudflare:

npx https://prerelease-registry.devprod.cloudflare.dev/workers-sdk/runs/14468730355/npm-package-create-cloudflare-8889 --no-auto-update

@cloudflare/kv-asset-handler:

npm install https://prerelease-registry.devprod.cloudflare.dev/workers-sdk/runs/14468730355/npm-package-cloudflare-kv-asset-handler-8889

miniflare:

npm install https://prerelease-registry.devprod.cloudflare.dev/workers-sdk/runs/14468730355/npm-package-miniflare-8889

@cloudflare/pages-shared:

npm install https://prerelease-registry.devprod.cloudflare.dev/workers-sdk/runs/14468730355/npm-package-cloudflare-pages-shared-8889

@cloudflare/unenv-preset:

npm install https://prerelease-registry.devprod.cloudflare.dev/workers-sdk/runs/14468730355/npm-package-cloudflare-unenv-preset-8889

@cloudflare/vite-plugin:

npm install https://prerelease-registry.devprod.cloudflare.dev/workers-sdk/runs/14468730355/npm-package-cloudflare-vite-plugin-8889

@cloudflare/vitest-pool-workers:

npm install https://prerelease-registry.devprod.cloudflare.dev/workers-sdk/runs/14468730355/npm-package-cloudflare-vitest-pool-workers-8889

@cloudflare/workers-editor-shared:

npm install https://prerelease-registry.devprod.cloudflare.dev/workers-sdk/runs/14468730355/npm-package-cloudflare-workers-editor-shared-8889

@cloudflare/workers-shared:

npm install https://prerelease-registry.devprod.cloudflare.dev/workers-sdk/runs/14468730355/npm-package-cloudflare-workers-shared-8889

@cloudflare/workflows-shared:

npm install https://prerelease-registry.devprod.cloudflare.dev/workers-sdk/runs/14468730355/npm-package-cloudflare-workflows-shared-8889

Note that these links will no longer work once the GitHub Actions artifact expires.