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{"@context":"https://schema.org","@type":"DiscussionForumPosting","headline":"[worker_threads] inherited --vfs-load is skipped when --import is present","articleBody":"### Version\n\nv24.x main\n\n### Proposed change\n\nA worker that inherits parent `execArgv` should apply an inherited `--vfs-load` mount before resolving its entry file, including when the parent also uses `--import`.\n\n### Current behavior\n\n`lib/internal/main/worker_thread.js` only calls `finishVfsMounts()` before loading the worker when there are no imports:\n\n```js\nif (imports.length === 0) {\n  finishVfsMounts()\n}\n```\n\nThe file-worker path reaches `Module.runMain(filename)`, which calls `resolveMainPath()` before `runEntryPointWithESMLoader()` installs the inherited VFS mount. A worker entry inside the inherited VFS therefore fails to resolve when the parent command also contains `--import`.\n\n### Steps to reproduce\n\nCreate `noop.mjs`, then:\n\n```js\n// app/index.js\nconst path = require('node:path')\nconst {Worker} = require('node:worker_threads')\n\nnew Worker(path.join(__dirname, 'worker.js'))\n  .on('message', console.log)\n  .on('error', console.error)\n```\n\n```js\n// app/worker.js\nrequire('node:worker_threads').parentPort.postMessage('ok')\n```\n\nRun:\n\n```console\nnode --experimental-vfs --import ./noop.mjs --vfs-load ./app\n```\n\nExpected: the worker loads `app/worker.js` from the inherited VFS and prints `ok`.\n\nActual: worker entry resolution happens before the inherited mount is installed, so loading fails.\n\n### Regression test\n\nExtend `test/parallel/test-vfs-load.js` with the existing inherited-worker scenario and an otherwise empty `--import` preload.\n\nI found no existing issue or PR covering `--vfs-load` together with `--import` for inherited workers.\n","author":{"url":"https://github.com/januththedev","@type":"Person","name":"januththedev"},"datePublished":"2026-09-25T01:09:01Z","url":"https://github.com/nodejs/node/issues/66270"}