[codex] Fix detached ArrayBuffer proxy DX#1985
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🦋 Changeset detectedLatest commit: e401ced The changes in this PR will be included in the next version bump. This PR includes changesets to release 20 packages
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📊 Benchmark Results
workflow with no steps💻 Local Development
▲ Production (Vercel)
🔍 Observability: Next.js (Turbopack) workflow with 1 step💻 Local Development
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🔍 Observability: Next.js (Turbopack) workflow with 10 sequential steps💻 Local Development
▲ Production (Vercel)
🔍 Observability: Next.js (Turbopack) workflow with 25 sequential steps💻 Local Development
▲ Production (Vercel)
🔍 Observability: Next.js (Turbopack) workflow with 50 sequential steps💻 Local Development
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🔍 Observability: Next.js (Turbopack) Promise.all with 10 concurrent steps💻 Local Development
▲ Production (Vercel)
🔍 Observability: Next.js (Turbopack) Promise.all with 25 concurrent steps💻 Local Development
▲ Production (Vercel)
🔍 Observability: Next.js (Turbopack) Promise.all with 50 concurrent steps💻 Local Development
▲ Production (Vercel)
🔍 Observability: Next.js (Turbopack) Promise.race with 10 concurrent steps💻 Local Development
▲ Production (Vercel)
🔍 Observability: Next.js (Turbopack) Promise.race with 25 concurrent steps💻 Local Development
▲ Production (Vercel)
🔍 Observability: Next.js (Turbopack) Promise.race with 50 concurrent steps💻 Local Development
▲ Production (Vercel)
🔍 Observability: Next.js (Turbopack) workflow with 10 sequential data payload steps (10KB)💻 Local Development
▲ Production (Vercel)
🔍 Observability: Next.js (Turbopack) workflow with 25 sequential data payload steps (10KB)💻 Local Development
▲ Production (Vercel)
🔍 Observability: Next.js (Turbopack) workflow with 50 sequential data payload steps (10KB)💻 Local Development
▲ Production (Vercel)
🔍 Observability: Next.js (Turbopack) workflow with 10 concurrent data payload steps (10KB)💻 Local Development
▲ Production (Vercel)
🔍 Observability: Next.js (Turbopack) workflow with 25 concurrent data payload steps (10KB)💻 Local Development
▲ Production (Vercel)
🔍 Observability: Next.js (Turbopack) workflow with 50 concurrent data payload steps (10KB)💻 Local Development
▲ Production (Vercel)
🔍 Observability: Next.js (Turbopack) Stream Benchmarks (includes TTFB metrics)workflow with stream💻 Local Development
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🔍 Observability: Next.js (Turbopack) stream pipeline with 5 transform steps (1MB)💻 Local Development
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🔍 Observability: Next.js (Turbopack) fan-out fan-in 10 streams (1MB each)💻 Local Development
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🔍 Observability: Next.js (Turbopack) SummaryFastest Framework by WorldWinner determined by most benchmark wins
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🧪 E2E Test Results❌ Some tests failed Summary
❌ Failed Tests▲ Vercel Production (2 failed)nextjs-turbopack (1 failed):
vite (1 failed):
🐘 Local Postgres (1 failed)nextjs-webpack-stable-lazy-discovery-enabled (1 failed):
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pranaygp
commented
May 14, 2026
| const DETACHED_ARRAYBUFFER_ERROR = | ||
| 'Cannot perform ArrayBuffer.prototype.slice on a detached ArrayBuffer'; | ||
| const PROXY_HANDLER_DOCS_URL = | ||
| 'https://useworkflow.dev/docs/getting-started/next#configure-proxy-handler'; |
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| 'https://useworkflow.dev/docs/getting-started/next#configure-proxy-handler'; | |
| 'https://workflow-sdk.dev/docs/getting-started/next#configure-proxy-handler'; |
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Pull request overview
Improves DX for the common "detached ArrayBuffer" failure mode where a Next.js proxy/middleware intercepts Workflow's internal /.well-known/workflow/* request, by upgrading the local queue's error log to actionable guidance, adding test coverage, surfacing the same hint in the Next.js getting-started docs, and making the relevant docs section directly linkable via URL hash.
Changes:
- Detect detached-ArrayBuffer errors (with cause-chain walk + cycle guard) in
world-localqueue's.catch()and replace the generic log with an actionable message + docs link, plus a regression test stubbingfetch. - Expand the v4/v5 Next.js getting-started "Configure Proxy Handler" accordion with a callout naming the exact error string, and give the accordion item an
h3anchor id (configure-proxy-handler). - Add a generic hash-open/scroll effect to the shared
Accordioncomponent so deep-links open the relevant accordion item; add a changeset for@workflow/world-local.
Reviewed changes
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Show a summary per file
| File | Description |
|---|---|
| packages/world-local/src/queue.ts | Adds detached-ArrayBuffer detection and the actionable replacement log path in the queue's catch handler. |
| packages/world-local/src/queue.test.ts | Adds a regression test that stubs fetch to reject with a detached-ArrayBuffer cause and asserts the new log format. |
| docs/content/docs/v5/getting-started/next.mdx | Adds error-string callout and an id="configure-proxy-handler" anchor inside the accordion trigger. |
| docs/content/docs/v4/getting-started/next.mdx | Same docs changes applied to the v4 guide. |
| docs/components/ui/accordion.tsx | Adds a useEffect that opens and scrolls to the accordion item matching window.location.hash on mount and hashchange. |
| .changeset/sixty-plants-shout.md | Patch changeset for @workflow/world-local. |
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TooTallNate
approved these changes
May 14, 2026
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Summary
@workflow/world-localqueue logging for theCannot perform ArrayBuffer.prototype.slice on a detached ArrayBufferfailure modeproxy.ts/middleware.tsmatcher fix when/.well-known/workflow/*is being interceptedRoot cause
When a Next.js proxy or middleware reads the request body for Workflow's internal
POST /.well-known/workflow/v1/flowrequest, the underlying ArrayBuffer can be detached before the executor reads it. The local queue then surfaces an undici-stylefetch failederror with a detached-ArrayBuffer cause, which is technically correct but not actionable enough on its own.What changed
packages/world-local/src/queue.tsfetchpathdocs/content/docs/v4/getting-started/next.mdxanddocs/content/docs/v5/getting-started/next.mdxCloses #1982
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