Allow Node.js' experimental inspector flags in next dev and next build#90603
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Allow Node.js' experimental inspector flags in next dev and next build#90603
next dev and next build#90603Conversation
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eps1lon
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Feb 26, 2026
| @@ -0,0 +1,4 @@ | |||
| export default async function Page() { | |||
| await fetch('https://next-data-api-endpoint.vercel.app/api/random') | |||
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Just added for manual testing that the Network tab works in Chrome DevTools
eps1lon
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Feb 26, 2026
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| if (process.version.startsWith('v20')) { | ||
| // --experimental-network-inspection is not supported in Node 20. | ||
| await expect(next.start()).rejects.toThrow() | ||
| } else { |
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Effectively makes the new behavior not covered by CI. Confirmed the test is working locally with Node.js 20 and Network monitor is functional. We still have the unit test.
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next dev and next buildnext dev and next build
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Manually verified with node --inspect --experimental-network-inspection packages/next/dist/bin/next test/e2e/node-cli-args.
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Fixes #87794
Fixes https://linear.app/vercel/issue/NEXT-4863/
Certain Node.js options are only supported as CLI args and not via a
NODE_OPTIONSenvironment variable. However,next devwas always passing along CLI args toNODE_OPTIONS.Now we forward a curated list of Node.js CLI args as CLI args to the dev server. Most interestingly, this enables having Node.js' experimental Network inspector running (
-experimental-network-inspection) to enable the Network tab of Chrome DevTools when attached to Node.js.All allowed CLI-only flags:
--experimental-network-inspection--experimental-storage-inspection--experimental-worker-inspection--experimental-inspector-network-resourcenext startwas already working.Holding off on adding better support via
next dev --experimental-network-inspectionbecause it's an experimental flag and I'm not too familiar with the current state.