SvelteKit deploy: the framework Worker packager resolves external packages with browser conditions, so `@sentry/sveltekit` fails to bundle

Read packages/void/src/cli/wrapper.ts around bundleEntry and its WORKER_CONDITIONS, then compare the lib build in packages/void/src/cli/cf-build-output.ts. Add a fixture package with both browser and workerd exports and check that both packaging paths resolve the Worker entry to the workerd file. Done means the regression test passes and the Sentry and postgres repros package with Worker conditions.

Problem

A SvelteKit + Void app imports @sentry/sveltekit (11.7.0) in src/hooks.server.ts. vp build passes. void deploy then fails at the packaging step, before anything is uploaded:

● sveltekit framework deploy
● Found 1 migration
◇ Bundling worker...
■ Build failed with 1 error:

  Error: [vite+]: Rolldown failed to resolve import "$app/stores" from
  "…/node_modules/@sentry/sveltekit/build/esm/client/svelte4BrowserTracing.js".
  This is most likely unintended because it can break your application at
  runtime.
  If you do want to externalize this module explicitly add it to
  `build.rolldownOptions.external`

The void deploy --platform cloudflare packager has the same problem and gives the same error.

pg/MySQL SvelteKit apps hit it too after #413, with the same error.

The same cause can also fail without any error at build time. postgres (3.4.9) packages fine, but the packager picks its Node build. Node's net/crypto/stream become an empty stub, so the first query fails in workerd:

• nodejs_als (the SvelteKit preset default): ReferenceError: Buffer is not defined
• nodejs_als + nodejs_compat: TypeError: import___vite_browser_external.default.Socket is not a constructor

Repro

Start from playground/sveltekit (D1 + KV, @sveltejs/adapter-cloudflare 8, Kit 3).

1. Add a dependency: "@sentry/sveltekit": "11.7.0".
2. Add src/hooks.server.ts:

   import * as Sentry from '@sentry/sveltekit';
   import { sequence } from '@sveltejs/kit/hooks';
   
   export const handle = sequence(
     Sentry.initCloudflareSentryHandle({ dsn: 'https://[email protected]/1', tracesSampleRate: 1 }),
     Sentry.sentryHandle(),
   );
   export const handleError = Sentry.handleErrorWithSentry();
   

3. Run:

   vp build                   # passes
   void deploy --skip-build   # fails at "Bundling worker..."
   

   For the native path, call prepareCfFrameworkBuildOutput (void deploy --platform cloudflare runs it as a preflight) on the same build. It fails with the same error.

Cause

Kit's server build leaves @sentry/sveltekit as a bare import (.svelte-kit/output/server/entries/hooks.server.js: import * as Sentry from "@sentry/sveltekit"). Void then bundles the adapter's _worker.js with a Vite lib build. That build has no ssr and no resolve.conditions, so Vite uses its client environment, with conditions ["module","browser","development|production"].

vp build (Kit + adapter-cloudflare)
  └─ .svelte-kit/cloudflare/_worker.js ──> hooks.server.js ──> "@sentry/sveltekit" (external)
            │
  void deploy                                void deploy --platform cloudflare
  runFrameworkDeploy                         prepareCfFrameworkBuildOutput
  bundleEntry  (wrapper.ts:520)              prepareBundledBuildOutput (cf-build-output.ts:205)
            └──── vite build({ build: { lib } }) → client env, "browser" condition ────┘
                                     │
   @sentry/sveltekit → build/esm/index.client.js → … → client/svelte4BrowserTracing.js
                                     └─ import "$app/stores"  ✗ (exists only inside Kit's build)

Code (on main, b58300ff8):

• packages/void/src/cli/preset.ts:115-124: the sveltekit preset sets bundle: true (:123). It is the only preset that does.
• packages/void/src/cli/deploy-managed-framework.ts:133-135: the hosted deploy calls bundleEntry(root, originalEntry).
• packages/void/src/cli/wrapper.ts:520-553: bundleEntry runs build({ root, build: { lib: { entry, formats: ['es'] }, … } }) and sets no conditions.
• packages/void/src/cli/deploy-cloudflare-build.ts:326-336: the native deploy runs prepareCfFrameworkBuildOutput for every worker-output preset (SvelteKit, Nuxt, Analog, Astro), as a preflight before remote changes. Only SvelteKit was tested.
• packages/void/src/cli/cf-build-output.ts:205-229: prepareBundledBuildOutput is the same kind of lib build (configFile: false, lib at :225).
• packages/void/src/plugin-framework.ts:280-321: for pg/MySQL, the void:sveltekit-worker-build plugin moves only void, drizzle-orm, the driver and packages that import void into Kit's workerd build. "Other dependencies stay external" (:287), so they still reach the browser-condition packager.

@sentry/[email protected] package.json → exports["."]:

{
  "types": "./build/types/index.types.d.ts",
  "workerd": { "import": "./build/esm/index.workerd.js", "require": "./build/cjs/index.workerd.js" },
  "worker":  { "import": "./build/esm/index.worker.js",  "require": "./build/cjs/index.worker.js" },
  "browser": { "import": "./build/esm/index.client.js",  "require": "./build/cjs/index.client.js" },
  "node":    { "import": "./build/esm/index.server.js",  "require": "./build/cjs/index.server.js" },
  "default": { "import": "./build/esm/index.server.js",  "require": "./build/cjs/index.server.js" }
}

With the client conditions, only browser matches, so the import resolves to index.client.js. That file is browser code: it pulls in Kit's $app/* modules and does not export initCloudflareSentryHandle or sentryHandle.

[email protected] exports["."] is { "workerd": "./cf/src/index.js", "import": "./src/index.js", … }. The client conditions skip workerd and match import, which is the Node build.

Check: the same bundleEntry options plus only resolve.conditions: ['workerd','worker','browser','module','import','default']:

• @sentry/sveltekit resolves to index.workerd.js. The build passes, and the Worker returns 200 for / in Miniflare with nodejs_als.
• postgres resolves to cf/src/index.js. The query reaches a real socket connect.

Suggested fix

Give both lib builds Worker resolve conditions. wrapper.ts:315-316 already defines WORKER_CONDITIONS and uses it for the SQL driver bundle (wrapper.ts:353-357). Use it in bundleEntry and prepareBundledBuildOutput (resolve: { conditions: WORKER_CONDITIONS }). prepareCfStaticBuildOutput (cf-build-output.ts:256) shares prepareBundledBuildOutput, so it gets the same change. Add a regression test with a fixture package that has both browser and workerd exports, and check that the packaged Worker uses the workerd file.

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