fix(world-vercel): hold the ws channel registry on globalThis by shalabhc · Pull Request #3699 · vercel/workflow

shalabhc · 2026-08-20T19:37:58Z

Due to bundling the world-vercel (#3493), we can have two copies of the module which cause websockets to not work from durabench.

Note in SDK use from e2e tests I have seen websockets work just fine. It breaks on durabench because of it's instrumentation initialization.

This PR fixes the issue by moving const transports out of module state into globalThis.

Details

## What

The WS events transport's channel registry moves from module scope onto a
Symbol.for() key on globalThis — the same technique @workflow/core already
uses for the World cache — along with the two once-per-process log latches.

Why

The transport's open and its lookup are reached through two different World
instances:

openWsChannel runs inside world-vercel's createQueueHandler, and the
runtime builds that consumer from getWorldHandlers();
a write reaches resolveWsTransport (a lookup, never a create) through
getWorld().

Those are two createWorld() calls, cached under two different globalThis
symbols in core. The only thing that made them meet was sharing one module
instance of this package, because const transports was module-scope.

#3493 bundled @workflow/world-vercel into the Next.js server output instead of
leaving it in serverExternalPackages. Next then gives the instrumentation.ts
entry its own copy of the module, separate from the route entries. So in an
app whose register() warms the world:

// instrumentation.ts
const { getWorld } = await import("workflow/runtime");
await getWorld();          // events-writing World, built in the instrumentation copy

…the flow route's later getWorldHandlers() builds the consumer's World in the
route copy. Opens land in one Map; every lookup reads the other, empty one.
The socket is opened and carries nothing — every event silently falls back to
HTTP, deterministically, for the life of the process. That is what
vercel-labs/durabench's apps/workflow-host hit: sockets in the trace, zero
event frames on them.

Nothing about the WS design was wrong, and this is not a reason to revert #3493
(its cold-start win is real). A module-scope singleton in a package that a
bundler may duplicate is the bug.

Verification

packages/world-vercel: 532 unit tests pass, typecheck and Biome clean.
Two new tests in ws-transport.test.ts: the registry is the object on
globalThis (and is evicted on release), and resolveWsTransport resolves a
channel another copy of this module registered — the regression this fixes.

Out-of-tree repro (minimal Next app, a node_modules package shaped like this
one, two globalThis-cached worlds, one variable at a time), on Next 16.2.11
and 16.3.1, webpack and Turbopack:

world pkg	`register()` warms the world	before this change	with the fix
bundled (post-[next] Bundle the Vercel world into the Next.js server output #3493)	yes	`http` (two Maps, `hit=false`)	`ws`
external (pre-[next] Bundle the Vercel world into the Next.js server output #3493)	yes	`ws`	`ws`
bundled (post-[next] Bundle the Vercel world into the Next.js server output #3493)	no	`ws`	`ws`

With the fix the two module instances still exist — the open logs one instance
id and the lookup another — but they share the registry, so the lookup hits.

Notes for review

The symbol carries a /v1 suffix so a future change to WsEventsTransport's
shape gets a fresh registry rather than a structurally-incompatible hit from an
older copy sharing the process. Cross-copy use is structural (request,
release, close); there is no instanceof on the transport.
Deliberately not in this PR, and worth doing separately: a debug breadcrumb
when resolveWsTransport misses (the silence here cost several
investigations); a transport assertion in the e2e-vercel-ws-transport lane,
which today passes whether events go over WS or fall back; and re-combining
getWorld/getWorldHandlers, which the code comment in
packages/core/src/runtime/world.ts already contemplates and which is what
turned "duplicated module" into a systematic miss rather than a race.
The workbench app that lane deploys only calls registerOTel in its
instrumentation, which is why CI never saw this; adding a world warm-up there
would give the lane the failing shape.

changeset-bot · 2026-08-20T19:38:02Z

🦋 Changeset detected

Latest commit: 3d940b8

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

This PR includes changesets to release 17 packages

Name	Type
@workflow/world-vercel	Patch
@workflow/cli	Patch
@workflow/core	Patch
@workflow/web	Patch
workflow	Patch
@workflow/world-testing	Patch
@workflow/builders	Patch
@workflow/next	Patch
@workflow/nitro	Patch
@workflow/vitest	Patch
@workflow/web-shared	Patch
@workflow/astro	Patch
@workflow/nest	Patch
@workflow/rollup	Patch
@workflow/sveltekit	Patch
@workflow/vite	Patch
@workflow/nuxt	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

vercel · 2026-08-20T19:38:07Z

The latest updates on your projects. Learn more about Vercel for GitHub.

Project	Deployment	Actions	Updated (UTC)
example-nextjs-workflow-turbopack	Ready	Preview	Aug 20, 2026 8:55pm
example-nextjs-workflow-webpack	Ready	Preview	Aug 20, 2026 8:55pm
example-workflow	Ready	Preview	Aug 20, 2026 8:55pm
workbench-astro-workflow	Ready	Preview	Aug 20, 2026 8:55pm
workbench-express-workflow	Ready	Preview	Aug 20, 2026 8:55pm
workbench-fastify-workflow	Ready	Preview	Aug 20, 2026 8:55pm
workbench-hono-workflow	Ready	Preview	Aug 20, 2026 8:55pm
workbench-nestjs-workflow	Ready	Preview	Aug 20, 2026 8:55pm
workbench-nitro-workflow	Ready	Preview	Aug 20, 2026 8:55pm
workbench-nuxt-workflow	Ready	Preview	Aug 20, 2026 8:55pm
workbench-python-workflow	Ready	Preview	Aug 20, 2026 8:55pm
workbench-sveltekit-workflow	Ready	Preview	Aug 20, 2026 8:55pm
workbench-tanstack-start-workflow	Ready	Preview	Aug 20, 2026 8:55pm
workbench-vite-workflow	Ready	Preview	Aug 20, 2026 8:55pm
workflow-docs	Ready	Preview, v0	Aug 20, 2026 8:55pm
workflow-swc-playground	Ready	Preview	Aug 20, 2026 8:55pm
workflow-tarballs	Ready	Preview	Aug 20, 2026 8:55pm
workflow-web	Ready	Preview	Aug 20, 2026 8:55pm

github-actions · 2026-08-20T19:38:19Z

🧪 E2E Test Results

❌ Some tests failed

❌ Failed E2E Tests

▲ Vercel Production (235 failed)

astro-node (6 failed):

hookCleanupTestWorkflow - hook token reuse after workflow completion | wrun_41M0GFJPPC0GYXBK33KRXND1AA | 🔍 observability
hookGetConflictWorkflow - hook.getConflict() resolves with the conflicting run when token is already registered | wrun_41M0GFKTSP0GG7FBCDQ0RMBP81 | 🔍 observability
setAttributes start: initial attributes are seeded on run creation
setAttributes start: reserved-prefix initial attributes are seeded with allowReservedAttributes
setAttributes setAttributesWorkflow: workflow-body calls append native attr_set events and merge correctly
setAttributes fire-and-forget: void setAttributes lands without awaiting

astro-quickjs (9 failed):

hookCleanupTestWorkflow - hook token reuse after workflow completion | wrun_41M0GFJPPC0GYXBK33KRXND1AA | 🔍 observability
concurrent hook token conflict - two workflows cannot use the same hook token simultaneously | wrun_41M0GFJF9Q0GT52K3YPD2X0SEN | 🔍 observability
hookGetConflictWorkflow - hook.getConflict() resolves with the conflicting run when token is already registered | wrun_41M0GFKTSP0GG7FBCDQ0RMBP81 | 🔍 observability
hookMinRetentionWorkflow - terminal Hook cannot resume and its token stays unavailable | wrun_41M0GFNFHC0GTK4YT3SQPJR3Z8 | 🔍 observability
setAttributes start: reserved-prefix initial attributes are seeded with allowReservedAttributes
setAttributes setAttributesWorkflow: workflow-body calls append native attr_set events and merge correctly
setAttributes fire-and-forget: void setAttributes lands without awaiting
setAttributes Promise.all of disjoint-key writes: every key lands
setAttributes validation DX: invalid writes throw catchable FatalErrors naming rule and limit

example-node (9 failed):

hookCleanupTestWorkflow - hook token reuse after workflow completion | wrun_41M0GFJPPC0GYXBK33KRXND1AA | 🔍 observability
concurrent hook token conflict - two workflows cannot use the same hook token simultaneously | wrun_41M0GFJF9Q0GT52K3YPD2X0SEN | 🔍 observability
hookMinRetentionWorkflow - terminal Hook cannot resume and its token stays unavailable | wrun_41M0GFNFHC0GTK4YT3SQPJR3Z8 | 🔍 observability
setAttributes start: initial attributes are seeded on run creation
setAttributes start: reserved-prefix initial attributes are seeded with allowReservedAttributes
setAttributes setAttributesWorkflow: workflow-body calls append native attr_set events and merge correctly
setAttributes setAttributesInsideStepWorkflow: step-body calls append attributed native events
setAttributes fire-and-forget: void setAttributes lands without awaiting
setAttributes Promise.all of disjoint-key writes: every key lands

example-quickjs (9 failed):

hookCleanupTestWorkflow - hook token reuse after workflow completion | wrun_41M0GFJPPC0GYXBK33KRXND1AA | 🔍 observability
hookGetConflictWorkflow - hook.getConflict() resolves with the conflicting run when token is already registered | wrun_41M0GFKTSP0GG7FBCDQ0RMBP81 | 🔍 observability
setAttributes start: initial attributes are seeded on run creation
setAttributes start: reserved-prefix initial attributes are seeded with allowReservedAttributes
setAttributes setAttributesWorkflow: workflow-body calls append native attr_set events and merge correctly
setAttributes setAttributesInsideStepWorkflow: step-body calls append attributed native events
setAttributes fire-and-forget: void setAttributes lands without awaiting
setAttributes Promise.all of disjoint-key writes: every key lands
setAttributes validation DX: invalid writes throw catchable FatalErrors naming rule and limit

express-node (8 failed):

hookCleanupTestWorkflow - hook token reuse after workflow completion | wrun_41M0GFJPPC0GYXBK33KRXND1AA | 🔍 observability
concurrent hook token conflict - two workflows cannot use the same hook token simultaneously | wrun_41M0GFJF9Q0GT52K3YPD2X0SEN | 🔍 observability
setAttributes start: initial attributes are seeded on run creation
setAttributes start: reserved-prefix initial attributes are seeded with allowReservedAttributes
setAttributes setAttributesWorkflow: workflow-body calls append native attr_set events and merge correctly
setAttributes setAttributesInsideStepWorkflow: step-body calls append attributed native events
setAttributes fire-and-forget: void setAttributes lands without awaiting
setAttributes Promise.all of disjoint-key writes: every key lands

express-quickjs (9 failed):

hookCleanupTestWorkflow - hook token reuse after workflow completion | wrun_41M0GFJPPC0GYXBK33KRXND1AA | 🔍 observability
concurrent hook token conflict - two workflows cannot use the same hook token simultaneously | wrun_41M0GFJF9Q0GT52K3YPD2X0SEN | 🔍 observability
hookGetConflictWorkflow - hook.getConflict() resolves with the conflicting run when token is already registered | wrun_41M0GFKTSP0GG7FBCDQ0RMBP81 | 🔍 observability
setAttributes start: initial attributes are seeded on run creation
setAttributes start: reserved-prefix initial attributes are seeded with allowReservedAttributes
setAttributes setAttributesWorkflow: workflow-body calls append native attr_set events and merge correctly
setAttributes setAttributesInsideStepWorkflow: step-body calls append attributed native events
setAttributes fire-and-forget: void setAttributes lands without awaiting
setAttributes Promise.all of disjoint-key writes: every key lands

fastify-node (11 failed):

hookCleanupTestWorkflow - hook token reuse after workflow completion | wrun_41M0GFJPPC0GYXBK33KRXND1AA | 🔍 observability
concurrent hook token conflict - two workflows cannot use the same hook token simultaneously | wrun_41M0GFJF9Q0GT52K3YPD2X0SEN | 🔍 observability
hookGetConflictWorkflow - hook.getConflict() resolves with the conflicting run when token is already registered | wrun_41M0GFKTSP0GG7FBCDQ0RMBP81 | 🔍 observability
hookMinRetentionWorkflow - terminal Hook cannot resume and its token stays unavailable | wrun_41M0GFNFHC0GTK4YT3SQPJR3Z8 | 🔍 observability
setAttributes start: initial attributes are seeded on run creation
setAttributes start: reserved-prefix initial attributes are seeded with allowReservedAttributes
setAttributes setAttributesWorkflow: workflow-body calls append native attr_set events and merge correctly
setAttributes setAttributesInsideStepWorkflow: step-body calls append attributed native events
setAttributes fire-and-forget: void setAttributes lands without awaiting
setAttributes Promise.all of disjoint-key writes: every key lands
setAttributes validation DX: invalid writes throw catchable FatalErrors naming rule and limit

fastify-quickjs (11 failed):

hookCleanupTestWorkflow - hook token reuse after workflow completion | wrun_41M0GFJPPC0GYXBK33KRXND1AA | 🔍 observability
concurrent hook token conflict - two workflows cannot use the same hook token simultaneously | wrun_41M0GFJF9Q0GT52K3YPD2X0SEN | 🔍 observability
hookGetConflictWorkflow - hook.getConflict() resolves with the conflicting run when token is already registered | wrun_41M0GFKTSP0GG7FBCDQ0RMBP81 | 🔍 observability
hookMinRetentionWorkflow - terminal Hook cannot resume and its token stays unavailable | wrun_41M0GFNFHC0GTK4YT3SQPJR3Z8 | 🔍 observability
setAttributes start: initial attributes are seeded on run creation
setAttributes start: reserved-prefix initial attributes are seeded with allowReservedAttributes
setAttributes setAttributesWorkflow: workflow-body calls append native attr_set events and merge correctly
setAttributes setAttributesInsideStepWorkflow: step-body calls append attributed native events
setAttributes fire-and-forget: void setAttributes lands without awaiting
setAttributes Promise.all of disjoint-key writes: every key lands
setAttributes workflow throws after awaited setAttributes: attribute still persists on the failed run

hono-node (8 failed):

hookCleanupTestWorkflow - hook token reuse after workflow completion | wrun_41M0GFJPPC0GYXBK33KRXND1AA | 🔍 observability
concurrent hook token conflict - two workflows cannot use the same hook token simultaneously | wrun_41M0GFJF9Q0GT52K3YPD2X0SEN | 🔍 observability
hookGetConflictWorkflow - hook.getConflict() resolves with the conflicting run when token is already registered | wrun_41M0GFKTSP0GG7FBCDQ0RMBP81 | 🔍 observability
setAttributes start: initial attributes are seeded on run creation
setAttributes start: reserved-prefix initial attributes are seeded with allowReservedAttributes
setAttributes setAttributesWorkflow: workflow-body calls append native attr_set events and merge correctly
setAttributes setAttributesInsideStepWorkflow: step-body calls append attributed native events
setAttributes fire-and-forget: void setAttributes lands without awaiting

hono-quickjs (7 failed):

hookCleanupTestWorkflow - hook token reuse after workflow completion | wrun_41M0GFJPPC0GYXBK33KRXND1AA | 🔍 observability
concurrent hook token conflict - two workflows cannot use the same hook token simultaneously | wrun_41M0GFJF9Q0GT52K3YPD2X0SEN | 🔍 observability
hookGetConflictWorkflow - hook.getConflict() resolves with the conflicting run when token is already registered | wrun_41M0GFKTSP0GG7FBCDQ0RMBP81 | 🔍 observability
setAttributes start: initial attributes are seeded on run creation
setAttributes start: reserved-prefix initial attributes are seeded with allowReservedAttributes
setAttributes setAttributesInsideStepWorkflow: step-body calls append attributed native events
setAttributes fire-and-forget: void setAttributes lands without awaiting

nest-node (12 failed):

hookCleanupTestWorkflow - hook token reuse after workflow completion | wrun_41M0GFJPPC0GYXBK33KRXND1AA | 🔍 observability
concurrent hook token conflict - two workflows cannot use the same hook token simultaneously | wrun_41M0GFJF9Q0GT52K3YPD2X0SEN | 🔍 observability
hookGetConflictWorkflow - hook.getConflict() resolves with the conflicting run when token is already registered | wrun_41M0GFKTSP0GG7FBCDQ0RMBP81 | 🔍 observability
hookMinRetentionWorkflow - terminal Hook cannot resume and its token stays unavailable | wrun_41M0GFNFHC0GTK4YT3SQPJR3Z8 | 🔍 observability
setAttributes start: initial attributes are seeded on run creation
setAttributes start: reserved-prefix initial attributes are seeded with allowReservedAttributes
setAttributes setAttributesWorkflow: workflow-body calls append native attr_set events and merge correctly
setAttributes setAttributesInsideStepWorkflow: step-body calls append attributed native events
setAttributes fire-and-forget: void setAttributes lands without awaiting
setAttributes Promise.all of disjoint-key writes: every key lands
setAttributes workflow throws after awaited setAttributes: attribute still persists on the failed run
setAttributes validation DX: invalid writes throw catchable FatalErrors naming rule and limit

nest-quickjs (9 failed):

hookCleanupTestWorkflow - hook token reuse after workflow completion | wrun_41M0GFJPPC0GYXBK33KRXND1AA | 🔍 observability
concurrent hook token conflict - two workflows cannot use the same hook token simultaneously | wrun_41M0GFJF9Q0GT52K3YPD2X0SEN | 🔍 observability
hookGetConflictWorkflow - hook.getConflict() resolves with the conflicting run when token is already registered | wrun_41M0GFKTSP0GG7FBCDQ0RMBP81 | 🔍 observability
setAttributes start: initial attributes are seeded on run creation
setAttributes start: reserved-prefix initial attributes are seeded with allowReservedAttributes
setAttributes setAttributesWorkflow: workflow-body calls append native attr_set events and merge correctly
setAttributes setAttributesInsideStepWorkflow: step-body calls append attributed native events
setAttributes fire-and-forget: void setAttributes lands without awaiting
setAttributes validation DX: invalid writes throw catchable FatalErrors naming rule and limit

nextjs-turbopack-node (4 failed):

hookCleanupTestWorkflow - hook token reuse after workflow completion | wrun_41M0GFJPPC0GYXBK33KRXND1AA | 🔍 observability
hookGetConflictWorkflow - hook.getConflict() resolves with the conflicting run when token is already registered | wrun_41M0GFKTSP0GG7FBCDQ0RMBP81 | 🔍 observability
setAttributes fire-and-forget: void setAttributes lands without awaiting
setAttributes workflow throws after awaited setAttributes: attribute still persists on the failed run

nextjs-turbopack-quickjs (9 failed):

hookCleanupTestWorkflow - hook token reuse after workflow completion | wrun_41M0GFJPPC0GYXBK33KRXND1AA | 🔍 observability
concurrent hook token conflict - two workflows cannot use the same hook token simultaneously | wrun_41M0GFJF9Q0GT52K3YPD2X0SEN | 🔍 observability
hookGetConflictWorkflow - hook.getConflict() resolves with the conflicting run when token is already registered | wrun_41M0GFKTSP0GG7FBCDQ0RMBP81 | 🔍 observability
setAttributes start: initial attributes are seeded on run creation
setAttributes start: reserved-prefix initial attributes are seeded with allowReservedAttributes
setAttributes setAttributesWorkflow: workflow-body calls append native attr_set events and merge correctly
setAttributes setAttributesInsideStepWorkflow: step-body calls append attributed native events
setAttributes fire-and-forget: void setAttributes lands without awaiting
setAttributes validation DX: invalid writes throw catchable FatalErrors naming rule and limit

nextjs-webpack-node (10 failed):

hookCleanupTestWorkflow - hook token reuse after workflow completion | wrun_41M0GFJPPC0GYXBK33KRXND1AA | 🔍 observability
concurrent hook token conflict - two workflows cannot use the same hook token simultaneously | wrun_41M0GFJF9Q0GT52K3YPD2X0SEN | 🔍 observability
hookGetConflictWorkflow - hook.getConflict() resolves with the conflicting run when token is already registered | wrun_41M0GFKTSP0GG7FBCDQ0RMBP81 | 🔍 observability
hookMinRetentionWorkflow - terminal Hook cannot resume and its token stays unavailable | wrun_41M0GFNFHC0GTK4YT3SQPJR3Z8 | 🔍 observability
setAttributes start: initial attributes are seeded on run creation
setAttributes start: reserved-prefix initial attributes are seeded with allowReservedAttributes
setAttributes setAttributesWorkflow: workflow-body calls append native attr_set events and merge correctly
setAttributes setAttributesInsideStepWorkflow: step-body calls append attributed native events
setAttributes fire-and-forget: void setAttributes lands without awaiting
setAttributes Promise.all of disjoint-key writes: every key lands

nextjs-webpack-quickjs (9 failed):

hookCleanupTestWorkflow - hook token reuse after workflow completion | wrun_41M0GFJPPC0GYXBK33KRXND1AA | 🔍 observability
concurrent hook token conflict - two workflows cannot use the same hook token simultaneously | wrun_41M0GFJF9Q0GT52K3YPD2X0SEN | 🔍 observability
hookGetConflictWorkflow - hook.getConflict() resolves with the conflicting run when token is already registered | wrun_41M0GFKTSP0GG7FBCDQ0RMBP81 | 🔍 observability
setAttributes start: initial attributes are seeded on run creation
setAttributes start: reserved-prefix initial attributes are seeded with allowReservedAttributes
setAttributes setAttributesWorkflow: workflow-body calls append native attr_set events and merge correctly
setAttributes setAttributesInsideStepWorkflow: step-body calls append attributed native events
setAttributes fire-and-forget: void setAttributes lands without awaiting
setAttributes Promise.all of disjoint-key writes: every key lands

nitro-node (9 failed):

hookCleanupTestWorkflow - hook token reuse after workflow completion | wrun_41M0GFJPPC0GYXBK33KRXND1AA | 🔍 observability
hookGetConflictWorkflow - hook.getConflict() resolves with the conflicting run when token is already registered | wrun_41M0GFKTSP0GG7FBCDQ0RMBP81 | 🔍 observability
hookMinRetentionWorkflow - terminal Hook cannot resume and its token stays unavailable | wrun_41M0GFNFHC0GTK4YT3SQPJR3Z8 | 🔍 observability
setAttributes start: initial attributes are seeded on run creation
setAttributes start: reserved-prefix initial attributes are seeded with allowReservedAttributes
setAttributes setAttributesWorkflow: workflow-body calls append native attr_set events and merge correctly
setAttributes setAttributesInsideStepWorkflow: step-body calls append attributed native events
setAttributes fire-and-forget: void setAttributes lands without awaiting
setAttributes Promise.all of disjoint-key writes: every key lands

nitro-quickjs (9 failed):

hookCleanupTestWorkflow - hook token reuse after workflow completion | wrun_41M0GFJPPC0GYXBK33KRXND1AA | 🔍 observability
concurrent hook token conflict - two workflows cannot use the same hook token simultaneously | wrun_41M0GFJF9Q0GT52K3YPD2X0SEN | 🔍 observability
hookGetConflictWorkflow - hook.getConflict() resolves with the conflicting run when token is already registered | wrun_41M0GFKTSP0GG7FBCDQ0RMBP81 | 🔍 observability
hookMinRetentionWorkflow - terminal Hook cannot resume and its token stays unavailable | wrun_41M0GFNFHC0GTK4YT3SQPJR3Z8 | 🔍 observability
setAttributes start: initial attributes are seeded on run creation
setAttributes start: reserved-prefix initial attributes are seeded with allowReservedAttributes
setAttributes setAttributesWorkflow: workflow-body calls append native attr_set events and merge correctly
setAttributes setAttributesInsideStepWorkflow: step-body calls append attributed native events
setAttributes fire-and-forget: void setAttributes lands without awaiting

nuxt-node (11 failed):

hookCleanupTestWorkflow - hook token reuse after workflow completion | wrun_41M0GFJPPC0GYXBK33KRXND1AA | 🔍 observability
concurrent hook token conflict - two workflows cannot use the same hook token simultaneously | wrun_41M0GFJF9Q0GT52K3YPD2X0SEN | 🔍 observability
hookGetConflictWorkflow - hook.getConflict() resolves with the conflicting run when token is already registered | wrun_41M0GFKTSP0GG7FBCDQ0RMBP81 | 🔍 observability
hookMinRetentionWorkflow - terminal Hook cannot resume and its token stays unavailable | wrun_41M0GFNFHC0GTK4YT3SQPJR3Z8 | 🔍 observability
setAttributes start: initial attributes are seeded on run creation
setAttributes start: reserved-prefix initial attributes are seeded with allowReservedAttributes
setAttributes setAttributesWorkflow: workflow-body calls append native attr_set events and merge correctly
setAttributes setAttributesInsideStepWorkflow: step-body calls append attributed native events
setAttributes fire-and-forget: void setAttributes lands without awaiting
setAttributes Promise.all of disjoint-key writes: every key lands
setAttributes validation DX: invalid writes throw catchable FatalErrors naming rule and limit

nuxt-quickjs (9 failed):

hookCleanupTestWorkflow - hook token reuse after workflow completion | wrun_41M0GFJPPC0GYXBK33KRXND1AA | 🔍 observability
concurrent hook token conflict - two workflows cannot use the same hook token simultaneously | wrun_41M0GFJF9Q0GT52K3YPD2X0SEN | 🔍 observability
hookGetConflictWorkflow - hook.getConflict() resolves with the conflicting run when token is already registered | wrun_41M0GFKTSP0GG7FBCDQ0RMBP81 | 🔍 observability
setAttributes start: initial attributes are seeded on run creation
setAttributes start: reserved-prefix initial attributes are seeded with allowReservedAttributes
setAttributes setAttributesWorkflow: workflow-body calls append native attr_set events and merge correctly
setAttributes setAttributesInsideStepWorkflow: step-body calls append attributed native events
setAttributes fire-and-forget: void setAttributes lands without awaiting
setAttributes Promise.all of disjoint-key writes: every key lands

sveltekit-node (9 failed):

hookCleanupTestWorkflow - hook token reuse after workflow completion | wrun_41M0GFJPPC0GYXBK33KRXND1AA | 🔍 observability
concurrent hook token conflict - two workflows cannot use the same hook token simultaneously | wrun_41M0GFJF9Q0GT52K3YPD2X0SEN | 🔍 observability
hookGetConflictWorkflow - hook.getConflict() resolves with the conflicting run when token is already registered | wrun_41M0GFKTSP0GG7FBCDQ0RMBP81 | 🔍 observability
setAttributes start: initial attributes are seeded on run creation
setAttributes start: reserved-prefix initial attributes are seeded with allowReservedAttributes
setAttributes setAttributesWorkflow: workflow-body calls append native attr_set events and merge correctly
setAttributes setAttributesInsideStepWorkflow: step-body calls append attributed native events
setAttributes fire-and-forget: void setAttributes lands without awaiting
setAttributes workflow throws after awaited setAttributes: attribute still persists on the failed run

sveltekit-quickjs (9 failed):

hookCleanupTestWorkflow - hook token reuse after workflow completion | wrun_41M0GFJPPC0GYXBK33KRXND1AA | 🔍 observability
hookGetConflictWorkflow - hook.getConflict() resolves with the conflicting run when token is already registered | wrun_41M0GFKTSP0GG7FBCDQ0RMBP81 | 🔍 observability
hookMinRetentionWorkflow - terminal Hook cannot resume and its token stays unavailable | wrun_41M0GFNFHC0GTK4YT3SQPJR3Z8 | 🔍 observability
setAttributes start: initial attributes are seeded on run creation
setAttributes start: reserved-prefix initial attributes are seeded with allowReservedAttributes
setAttributes setAttributesWorkflow: workflow-body calls append native attr_set events and merge correctly
setAttributes setAttributesInsideStepWorkflow: step-body calls append attributed native events
setAttributes fire-and-forget: void setAttributes lands without awaiting
setAttributes Promise.all of disjoint-key writes: every key lands

tanstack-start-node (10 failed):

hookCleanupTestWorkflow - hook token reuse after workflow completion | wrun_41M0GFJPPC0GYXBK33KRXND1AA | 🔍 observability
concurrent hook token conflict - two workflows cannot use the same hook token simultaneously | wrun_41M0GFJF9Q0GT52K3YPD2X0SEN | 🔍 observability
hookGetConflictWorkflow - hook.getConflict() resolves with the conflicting run when token is already registered | wrun_41M0GFKTSP0GG7FBCDQ0RMBP81 | 🔍 observability
hookMinRetentionWorkflow - terminal Hook cannot resume and its token stays unavailable | wrun_41M0GFNFHC0GTK4YT3SQPJR3Z8 | 🔍 observability
setAttributes start: initial attributes are seeded on run creation
setAttributes start: reserved-prefix initial attributes are seeded with allowReservedAttributes
setAttributes setAttributesWorkflow: workflow-body calls append native attr_set events and merge correctly
setAttributes fire-and-forget: void setAttributes lands without awaiting
setAttributes Promise.all of disjoint-key writes: every key lands
setAttributes validation DX: invalid writes throw catchable FatalErrors naming rule and limit

tanstack-start-quickjs (9 failed):

hookCleanupTestWorkflow - hook token reuse after workflow completion | wrun_41M0GFJPPC0GYXBK33KRXND1AA | 🔍 observability
hookGetConflictWorkflow - hook.getConflict() resolves with the conflicting run when token is already registered | wrun_41M0GFKTSP0GG7FBCDQ0RMBP81 | 🔍 observability
hookMinRetentionWorkflow - terminal Hook cannot resume and its token stays unavailable | wrun_41M0GFNFHC0GTK4YT3SQPJR3Z8 | 🔍 observability
setAttributes start: initial attributes are seeded on run creation
setAttributes start: reserved-prefix initial attributes are seeded with allowReservedAttributes
setAttributes setAttributesWorkflow: workflow-body calls append native attr_set events and merge correctly
setAttributes setAttributesInsideStepWorkflow: step-body calls append attributed native events
setAttributes fire-and-forget: void setAttributes lands without awaiting
setAttributes validation DX: invalid writes throw catchable FatalErrors naming rule and limit

vite-node (10 failed):

hookCleanupTestWorkflow - hook token reuse after workflow completion | wrun_41M0GFJPPC0GYXBK33KRXND1AA | 🔍 observability
concurrent hook token conflict - two workflows cannot use the same hook token simultaneously | wrun_41M0GFJF9Q0GT52K3YPD2X0SEN | 🔍 observability
hookGetConflictWorkflow - hook.getConflict() resolves with the conflicting run when token is already registered | wrun_41M0GFKTSP0GG7FBCDQ0RMBP81 | 🔍 observability
hookMinRetentionWorkflow - terminal Hook cannot resume and its token stays unavailable | wrun_41M0GFNFHC0GTK4YT3SQPJR3Z8 | 🔍 observability
setAttributes start: initial attributes are seeded on run creation
setAttributes start: reserved-prefix initial attributes are seeded with allowReservedAttributes
setAttributes setAttributesWorkflow: workflow-body calls append native attr_set events and merge correctly
setAttributes setAttributesInsideStepWorkflow: step-body calls append attributed native events
setAttributes fire-and-forget: void setAttributes lands without awaiting
setAttributes Promise.all of disjoint-key writes: every key lands

vite-quickjs (10 failed):

hookCleanupTestWorkflow - hook token reuse after workflow completion | wrun_41M0GFJPPC0GYXBK33KRXND1AA | 🔍 observability
concurrent hook token conflict - two workflows cannot use the same hook token simultaneously | wrun_41M0GFJF9Q0GT52K3YPD2X0SEN | 🔍 observability
hookGetConflictWorkflow - hook.getConflict() resolves with the conflicting run when token is already registered | wrun_41M0GFKTSP0GG7FBCDQ0RMBP81 | 🔍 observability
hookMinRetentionWorkflow - terminal Hook cannot resume and its token stays unavailable | wrun_41M0GFNFHC0GTK4YT3SQPJR3Z8 | 🔍 observability
setAttributes start: reserved-prefix initial attributes are seeded with allowReservedAttributes
setAttributes setAttributesWorkflow: workflow-body calls append native attr_set events and merge correctly
setAttributes setAttributesInsideStepWorkflow: step-body calls append attributed native events
setAttributes fire-and-forget: void setAttributes lands without awaiting
setAttributes Promise.all of disjoint-key writes: every key lands
setAttributes validation DX: invalid writes throw catchable FatalErrors naming rule and limit

💻 Local Development (4 failed)

nextjs-webpack-canary-node (1 failed):

runClassSerializationWorkflow - Run instances serialize across workflow/step boundaries | wrun_41M0GFPC0R0GGA9CR0D2NTZEYC

nextjs-webpack-stable-node (2 failed):

pages router addTenWorkflow via pages router
pages router sleepingWorkflow via pages router

nextjs-webpack-stable-quickjs (1 failed):

health check (CLI) - workflow health command reports healthy endpoints

⚠️ Flaky E2E Tests (passed on retry)

These tests failed at least once and passed on a retry. A recurring entry here is a real race worth investigating.

28 flaky tests

abortAnyInStepWorkflow: AbortSignal.any inside a step composes deserialized signals (nextjs-webpack)
abortParallelWorkflow: abort cancels all parallel steps (nuxt)
abortSurvivesReplayWorkflow: controller state consistent across replay (nextjs-webpack)
abortThrowIfAbortedWorkflow: throwIfAborted causes FatalError, no retries (nextjs-webpack)
addTenWorkflow via pages router (nextjs-webpack)
cancelRun via CLI - cancelling a running workflow (nextjs-turbopack)
concurrent hook token conflict - two workflows cannot use the same hook token simultaneously (nextjs-turbopack)
hookClaimOnlyMutexWorkflow - hook works as a pure run mutex without payload data (nextjs-webpack)
hookMinRetentionWorkflow - terminal Hook cannot resume and its token stays unavailable (express)
hookMinRetentionWorkflow - terminal Hook cannot resume and its token stays unavailable (hono)
hookMinRetentionWorkflow - terminal Hook cannot resume and its token stays unavailable (nuxt)
Promise.all of disjoint-key writes: every key lands (hono)
Promise.all of disjoint-key writes: every key lands (nest)
Promise.all of disjoint-key writes: every key lands (nitro)
Promise.all of disjoint-key writes: every key lands (sveltekit)
promiseAllWorkflow via pages router (nextjs-webpack)
setAttributesInsideStepWorkflow: step-body calls append attributed native events (astro)
setAttributesInsideStepWorkflow: step-body calls append attributed native events (tanstack-start)
sleepingWorkflow via pages router (nextjs-webpack)
spawnWorkflowFromStepWorkflow - spawning a child workflow using start() inside a step (nextjs-webpack)
start: initial attributes are seeded on run creation (nextjs-turbopack)
start: initial attributes are seeded on run creation (vite)
start: reserved-prefix initial attributes are seeded with allowReservedAttributes (nextjs-turbopack)
validation DX: invalid writes throw catchable FatalErrors naming rule and limit (nitro)
workflow throws after awaited setAttributes: attribute still persists on the failed run (example)
workflow throws after awaited setAttributes: attribute still persists on the failed run (nest)
workflow throws after awaited setAttributes: attribute still persists on the failed run (nextjs-webpack)
workflow throws after awaited setAttributes: attribute still persists on the failed run (vite)

🛠 Infra Events (absorbed by the harness)

Platform anomalies the e2e harness detected and worked around (e.g. a run the queue never picked up, replaced by a fresh run). Clustered timestamps indicate a backend blip; a steady drip indicates a platform issue worth escalating.

cold-start-warmup · suite warmup (tanstack-start) · at 20:56:36Z · abandoned wrun_01M0GFBDSHMR8XK4WAAG801DVB
run-pickup-stall · AllInOneService.processNumber - static workflow method using sibling static step methods (express) · at 20:58:17Z · abandoned wrun_01M0GFEWSGS7YFVPZP7QNX26H2

E2E Test Summary

Summary

	Passed	Failed	Skipped	Total
❌ ▲ Vercel Production	3343	235	742	4320
❌ 💻 Local Development	3918	4	558	4480
✅ 📦 Local Production	3922	0	558	4480
✅ 🐘 Local Postgres	3922	0	558	4480
✅ 🪟 Windows	320	0	0	320
✅ 🌐 Cross-language Conformance	9	0	132	141
✅ vercel-multi-region	27	0	0	27
Total	15461	239	2548	18248

Details by Category

❌ ▲ Vercel Production

App	Passed	Failed	Skipped
❌ astro-node	126	6	28
❌ astro-quickjs	123	9	28
❌ example-node	123	9	28
❌ example-quickjs	123	9	28
❌ express-node	124	8	28
❌ express-quickjs	123	9	28
❌ fastify-node	121	11	28
❌ fastify-quickjs	121	11	28
❌ hono-node	124	8	28
❌ hono-quickjs	125	7	28
❌ nest-node	120	12	28
❌ nest-quickjs	123	9	28
❌ nextjs-turbopack-node	153	4	3
❌ nextjs-turbopack-quickjs	148	9	3
❌ nextjs-webpack-node	147	10	3
❌ nextjs-webpack-quickjs	148	9	3
❌ nitro-node	123	9	28
❌ nitro-quickjs	123	9	28
❌ nuxt-node	121	11	28
❌ nuxt-quickjs	123	9	28
✅ python-node	8	0	152
❌ sveltekit-node	142	9	9
❌ sveltekit-quickjs	142	9	9
❌ tanstack-start-node	122	10	28
❌ tanstack-start-quickjs	123	9	28
❌ vite-node	122	10	28
❌ vite-quickjs	122	10	28

❌ 💻 Local Development

App	Passed	Failed	Skipped
✅ astro-stable-node	134	0	26
✅ astro-stable-quickjs	134	0	26
✅ express-stable-node	134	0	26
✅ express-stable-quickjs	134	0	26
✅ fastify-stable-node	134	0	26
✅ fastify-stable-quickjs	134	0	26
✅ hono-stable-node	134	0	26
✅ hono-stable-quickjs	134	0	26
✅ nest-stable-node	134	0	26
✅ nest-stable-quickjs	134	0	26
✅ nextjs-turbopack-canary-node	141	0	19
✅ nextjs-turbopack-canary-quickjs	141	0	19
✅ nextjs-turbopack-stable-node	160	0	0
✅ nextjs-turbopack-stable-quickjs	160	0	0
❌ nextjs-webpack-canary-node	140	1	19
✅ nextjs-webpack-canary-quickjs	141	0	19
❌ nextjs-webpack-stable-node	158	2	0
❌ nextjs-webpack-stable-quickjs	159	1	0
✅ nitro-stable-node	134	0	26
✅ nitro-stable-quickjs	134	0	26
✅ nuxt-stable-node	134	0	26
✅ nuxt-stable-quickjs	134	0	26
✅ sveltekit-stable-node	153	0	7
✅ sveltekit-stable-quickjs	153	0	7
✅ tanstack-start-node	134	0	26
✅ tanstack-start-quickjs	134	0	26
✅ vite-stable-node	134	0	26
✅ vite-stable-quickjs	134	0	26

✅ 📦 Local Production

App	Passed	Skipped
✅ astro-stable-node	134	26
✅ astro-stable-quickjs	134	26
✅ express-stable-node	134	26
✅ express-stable-quickjs	134	26
✅ fastify-stable-node	134	26
✅ fastify-stable-quickjs	134	26
✅ hono-stable-node	134	26
✅ hono-stable-quickjs	134	26
✅ nest-stable-node	134	26
✅ nest-stable-quickjs	134	26
✅ nextjs-turbopack-canary-node	141	19
✅ nextjs-turbopack-canary-quickjs	141	19
✅ nextjs-turbopack-stable-node	160	0
✅ nextjs-turbopack-stable-quickjs	160	0
✅ nextjs-webpack-canary-node	141	19
✅ nextjs-webpack-canary-quickjs	141	19
✅ nextjs-webpack-stable-node	160	0
✅ nextjs-webpack-stable-quickjs	160	0
✅ nitro-stable-node	134	26
✅ nitro-stable-quickjs	134	26
✅ nuxt-stable-node	134	26
✅ nuxt-stable-quickjs	134	26
✅ sveltekit-stable-node	153	7
✅ sveltekit-stable-quickjs	153	7
✅ tanstack-start-node	134	26
✅ tanstack-start-quickjs	134	26
✅ vite-stable-node	134	26
✅ vite-stable-quickjs	134	26

✅ 🐘 Local Postgres

App	Passed	Skipped
✅ astro-stable-node	134	26
✅ astro-stable-quickjs	134	26
✅ express-stable-node	134	26
✅ express-stable-quickjs	134	26
✅ fastify-stable-node	134	26
✅ fastify-stable-quickjs	134	26
✅ hono-stable-node	134	26
✅ hono-stable-quickjs	134	26
✅ nest-stable-node	134	26
✅ nest-stable-quickjs	134	26
✅ nextjs-turbopack-canary-node	141	19
✅ nextjs-turbopack-canary-quickjs	141	19
✅ nextjs-turbopack-stable-node	160	0
✅ nextjs-turbopack-stable-quickjs	160	0
✅ nextjs-webpack-canary-node	141	19
✅ nextjs-webpack-canary-quickjs	141	19
✅ nextjs-webpack-stable-node	160	0
✅ nextjs-webpack-stable-quickjs	160	0
✅ nitro-stable-node	134	26
✅ nitro-stable-quickjs	134	26
✅ nuxt-stable-node	134	26
✅ nuxt-stable-quickjs	134	26
✅ sveltekit-stable-node	153	7
✅ sveltekit-stable-quickjs	153	7
✅ tanstack-start-node	134	26
✅ tanstack-start-quickjs	134	26
✅ vite-stable-node	134	26
✅ vite-stable-quickjs	134	26

✅ 🪟 Windows

App	Passed	Failed	Skipped
✅ nextjs-turbopack-node	160	0	0
✅ nextjs-turbopack-quickjs	160	0	0

✅ 🌐 Cross-language Conformance

App	Passed	Failed	Skipped
✅ python	9	0	132

✅ vercel-multi-region

App	Passed	Failed	Skipped
✅ nextjs-turbopack	27	0	0

📋 View full workflow run

github-actions · 2026-08-20T19:38:22Z

📊 Workflow Benchmarks

❌ The benchmark run for 3d940b8 failed. See the run logs for details.

commit 5e30b16 · Thu, 20 Aug 2026 19:57:57 GMT · run logs

Backend: vercel · app: nextjs-turbopack

Metric	Scenario	Best (ms)	P75 (ms)	P90 (ms)	P99 (ms)	Samples
TTFS	step	1280 (+24%) 🔻	1386 🔴 (+22%) 🔻	1407 🔴 (+20%) 🔻	1772 🔴 (+45%) 🔻	30
TTFS	stream	1271 (+614%) 🔻	1388 🔴 (+24%) 🔻	1429 🔴 (+27%) 🔻	1438 🔴 (+23%) 🔻	30
TTFS	hook + stream	511 (+2.8%)	1677 🔴 (+16%) 🔻	1755 🔴 (+19%) 🔻	2073 🔴 (+34%) 🔻	30
Fan-out TTFS	Promise.all(100 steps)	540 (+36%) 🔻	868 (-3.0%)	899 (-49%) 💚	2203 (+17%) 🔻	10
Fan-out TTLS	Promise.all(100 steps)	4730 (-1.2%)	7893 (+28%) 🔻	9735 (+55%) 🔻	12654 (+76%) 🔻	10
STSO	1020 steps (inline)	122 (+1.7%)	169 (-32%) 💚	192 (-36%) 💚	353 (-30%) 💚	1019
WO	1020 steps	165458 (-30%) 💚	165458 (-30%) 💚	165458 (-30%) 💚	165458 (-30%) 💚	1
CRTT	first chunk (pooled)	104 (+13%)	166 (+26%) 🔻	282 (+87%) 🔻	3469 (+2002%) 🔻	28

Streams

Scenario	CRTT 1st	p75	p90	p99	CDV max	iters
paced control (100/s, 60B)	142 (+16%)	152 (+5%)	214 (-19%)	310 (-72%)	144 (-2%)	10
size sweep (100/s, 160B-12KB)	123 (-5%)	149 (-33%)	201 (-62%)	473 (-39%)	160 (-41%)	10
replay gateway-gpt-5.4-nano-2000t (1x)	151 (+25%)	145 (-1%)	190 (-26%)	668 (-5%)	263 (-49%)	3
replay eve-gpt-5.6-sol-2000t (1x)	245 (+92%)	165 (+9%)	228 (-11%)	734 (-13%)	363 (-28%)	2
replay eve-gpt-5.6-sol-2000t (2x)	326 (+167%)	210 (±0%)	351 (+9%)	1334 (-60%)	320 (-47%)	3

ℹ️ Metric definitions & methodology

_{Streams: first-chunk RTT (the stream-open path, before any buffering/backpressure), CRTT percentiles, and worst delivery stall (CDV max). Cells are medians across iterations; per-run values in the artifacts. No 🔴/🟢 marks until targets attach.}

_{Best/P75/P90/P99 deltas compare against the most recent benchmark run on main at the time of this run. 🔻 flags a delta worse than +15%, 💚 one better than −15%.}

_{Metrics — TTFS: time to first step body (in-deployment start() → first step body) · Fan-out TTFS: fan-out time to first step (in-deployment start() → first of the parallel step bodies to complete) · Fan-out TTLS: fan-out time to last step (in-deployment start() → last of the parallel step bodies to complete, i.e. when the Promise.all resolves) · STSO: step-to-step overhead (gap between consecutive step bodies) · WO: workflow overhead (whole-run time outside step bodies, in-deployment anchored) · CRTT: chunk round-trip time (per-chunk write → read latency, one clock domain: deployment → stream backend → same deployment) · CDV: chunk delay variation / delivery jitter (inter-arrival gap minus inter-write gap per seq-adjacent pair; skew-free; the row is each run's MAX positive value, so one stall moves it)}

_{Scenarios — step: one trivial no-op step, no stream; no hooks, so the run stays in turbo mode (in-process fast path) · stream: one streaming step; no hooks, so the run stays in turbo mode (in-process fast path) · hook + stream: registers a hook before one step, which exits turbo mode (dispatch path) · 1020 steps: 1020 trivial sequential steps; STSO is measured between consecutive steps in the given step ranges, and WO is the whole-run overhead outside step bodies · Promise.all(100 steps): 100 trivial no-op steps started together in a single Promise.all; Fan-out TTFS is the first of them to complete and Fan-out TTLS the last, both from the in-deployment clientStart, so their gap is the spread the runtime adds across the fan-out · paced control (100/s, 60B): the control: 300 tiny (~60B) deltas metronome-paced at 100/s — zero workload structure, so it reads the transport floor and flush cadence, and disambiguates transport-wide vs workload-specific when a replay row moves · size sweep (100/s, 160B-12KB): same pacing as the control with deltas padded in rotation across seven log-spaced sizes (~160B–12KB) — rotation decouples size from stream position, so it isolates whether chunk size causes latency · replay gateway-gpt-5.4-nano-2000t (1x): raw provider SSE cadence captured at the AI gateway boundary (gpt-5.4-nano, the most popular gateway model; per-token deltas p50 208B = the modal production chunk size), replayed exactly as measured — the typical customer's workload; its CDV is the typical customer's real delivery jitter · replay eve-gpt-5.6-sol-2000t (1x): a captured eve turn (gpt-5.6-sol, the most-used demanding eve model; ~2000 output tokens = production p50 turn length) replayed exactly as measured — eve's envelope protocol re-ships the cumulative message so sizes ramp 142B→13KB; the demanding outlier tenant's reality · replay eve-gpt-5.6-sol-2000t (2x): the same eve capture at 2x — the headroom/stress row; real fast-tier models emit the same chunk sizes at proportionally higher rate, so time compression is a faithful speed model · first chunk (pooled): every run's seq-0 RTT pooled across all stream scenarios — the first chunk precedes any workload differentiation, so pooling samples one shared stream-open path with exact percentiles}

_{Replay cadences (semantic sha256) — eve-gpt-5.6-sol-2000t eaf22f5946e7c61f3c65c7006d550df180cfabd4e706254a09f22aec0cfb420d · gateway-gpt-5.4-nano-2000t 6f24ac518b6b83ff1d0e85a5fe78230db192716d66a7fc6b2fe022752001d041}

_{🔴 marks a percentile over its target (within target is left unmarked). Targets (p75/p90/p99, ms) — TTFS 200/300/600}

_{All timestamps are deployment-side; runs are triggered in-deployment, so the CI runner and api.vercel.com sit outside every measured window. TTFS = start() → first step body (includes dispatch + any cold start); Fan-out TTFS/TTLS = first/last step completion of one Promise.all from the same anchor (the gap is the runtime’s fan-out spread); STSO/WO between step bodies; CRTT inside the workflow (excludes the api.vercel.com read path).}

_{Cold starts stay in the numbers (real bursty-workload latency, inflates P75+); Best is the warm floor.}

github-actions · 2026-08-20T19:41:30Z

Sim World

Simulated world deterministic testing for races. Traces

🟠 world-sim scenario book — 1 fail of 41 total

fence=per-spec

scenario	outcome	events	virt	replay
✅ `smoke-no-steps`	completed	3	0ms	ok
✅ `smoke-one-step`	completed	6	0ms	ok
✅ `hook-at-step-started`	completed	12	0ms	ok
✅ `hook-at-step-completed`	completed	12	0ms	ok
✅ `hook-at-hook-created`	completed	12	0ms	ok
✅ `deadline-hook-wins`	completed	7	1.0h	ok
✅ `deadline-expires`	completed	7	1.0h	ok
✅ `long-sleep`	completed	11	30.0d	ok
✅ `hook-never-arrives`	stalled	3	0ms	skipped
✅ `step-retries-twice`	completed	10	2.0s	ok
✅ `parallel-steps`	completed	9	0ms	ok
✅ `hook-on-execution-state`	completed	12	0ms	ok
✅ `peek-hook-before-branch`	completed	12	0ms	ok
✅ `peek-hook-after-branch`	completed	12	0ms	ok
✅ `peek-hook-at-registration`	completed	12	0ms	ok
✅ `race-hook-before-probe`	completed	12	0ms	ok
✅ `race-hook-after-probe`	completed	12	0ms	ok
✅ `race-duplicate-delivery`	completed	13	0ms	ok
✅ `attr-hook-before-step`	completed	11	0ms	ok
✅ `attr-hook-after-step`	completed	11	0ms	ok
✅ `attr-from-step-body`	completed	13	0ms	ok
✅ `fork-hook-after-timeout`	completed	14	1.0m	ok
✅ `fork-hook-before-timeout`	completed	14	1.0m	ok
✅ `count-hook-after-timeout`	completed	17	1.0m	ok
✅ `count-hook-before-timeout`	completed	20	1.0m	ok
✅ `stale-read-step-count-fork`	completed	20	1.0m	ok
✅ `stale-read-equal-step-counts`	completed	14	1.0m	ok
✅ `step-vs-step-fork`	completed	12	0ms	ok
✅ `step-vs-step-fork-fenced`	completed	12	0ms	ok
✅ `fence-catches-benign-direction`	completed	12	5ms	ok
✅ `in-flight-before-decision`	completed	17	1.0m	ok
❌ `in-flight-before-decision-counted`	completed	17	1.0m	ok
✅ `in-flight-after-decision`	completed	19	2.0m	ok
✅ `stale-read-step-count-fork-fenced`	completed	20	1.0m	ok
✅ `fork-hook-wins`	completed	13	1.0m	ok
✅ `fork-timeout-wins`	completed	13	1.0m	ok
✅ `unclaimed-payload-under-fork`	completed	17	1.0m	ok
✅ `claimed-payload-under-fork`	completed	17	1.0m	ok
✅ `writers-independent-step-bodies`	completed	12	0ms	ok
✅ `writers-scripted-tempo`	completed	12	0ms	ok
✅ `cancel-mid-step`	cancelled	7	0ms	skipped

Full trace: world-sim.txt

The WS events transport opens a channel from the queue consumer, which the runtime builds from `getWorldHandlers()`, and looks it up on the write path through `getWorld()` — two `createWorld()` calls cached under two different `globalThis` symbols in @workflow/core. The registry that joins them was a module-scope Map, so the handoff only worked while both calls ran in one module instance of this package. Since #3493 bundled the world into the Next.js server output instead of leaving it external, that is no longer guaranteed: Next gives the instrumentation entry its own copy of the module. An app whose `register()` warms the world (`await getWorld()`) therefore creates the events-writing World in the instrumentation copy and the queue consumer's World in the route entry, and every lookup reads an empty Map — sockets open and carry nothing, silently, for the life of the process. Move the registry and the two once-per-process log latches onto a `Symbol.for()` key on globalThis, the same technique core already uses for the World cache, so the transport is correct however many copies a bundler makes. Signed-off-by: Shalabh Chaturvedi <7066873+shalabhc@users.noreply.github.com> Co-Authored-By: Shalabh Chaturvedi <7066873+shalabhc@users.noreply.github.com> Signed-off-by: Shalabh Chaturvedi <7066873+shalabhc@users.noreply.github.com>

pranaygp · 2026-08-20T21:11:53Z

+'@workflow/world-vercel': patch
+---
+
+Hold the WebSocket events transport's channel registry on `globalThis` instead of at module scope, so an app that ends up with two copies of the bundled world in one process (for example a Next.js app whose `instrumentation.ts` warms the world) still resolves the channel its queue consumer opened instead of silently writing every event over HTTP.


pranaygp · 2026-08-20T21:12:50Z

+ * registry at module scope, opens went into one Map and every write read the
+ * other, empty one: socket open, every event silently on HTTP.
+ *
+ * `/v1` so a later change to `WsEventsTransport`'s shape gets a fresh registry


pranaygp

I suspect this is papering over a more global bug/regression from #3493 that's allowing duplicate instances of modules in the first place. maybe we can fix that instead of papering over the fix for websockets/transports specifically with this solution

vercel Bot deployed to Preview – workbench-python-workflow August 20, 2026 19:38 View deployment

vercel Bot deployed to Preview – workflow-web August 20, 2026 19:38 View deployment

vercel Bot deployed to Preview – workbench-nestjs-workflow August 20, 2026 19:39 View deployment

vercel Bot deployed to Preview – workflow-tarballs August 20, 2026 19:39 View deployment

vercel Bot deployed to Preview – workbench-hono-workflow August 20, 2026 19:39 View deployment

vercel Bot deployed to Preview – workbench-fastify-workflow August 20, 2026 19:39 View deployment

vercel Bot deployed to Preview – workbench-vite-workflow August 20, 2026 19:39 View deployment

vercel Bot deployed to Preview – workbench-tanstack-start-workflow August 20, 2026 19:39 View deployment

vercel Bot deployed to Preview – workbench-express-workflow August 20, 2026 19:39 View deployment

vercel Bot deployed to Preview – workbench-nitro-workflow August 20, 2026 19:39 View deployment

vercel Bot deployed to Preview – workbench-nuxt-workflow August 20, 2026 19:39 View deployment

vercel Bot deployed to Preview – workbench-astro-workflow August 20, 2026 19:39 View deployment

vercel Bot deployed to Preview – workbench-sveltekit-workflow August 20, 2026 19:39 View deployment

vercel Bot deployed to Preview – example-workflow August 20, 2026 19:39 View deployment

vercel Bot deployed to Preview – example-nextjs-workflow-turbopack August 20, 2026 19:39 View deployment

vercel Bot deployed to Preview – example-nextjs-workflow-webpack August 20, 2026 19:40 View deployment

vercel Bot deployed to Preview – workflow-docs August 20, 2026 19:40 View deployment

vercel Bot deployed to Preview – workflow-swc-playground August 20, 2026 19:41 View deployment

shalabhc marked this pull request as ready for review August 20, 2026 20:50

shalabhc requested a review from a team as a code owner August 20, 2026 20:50

shalabhc force-pushed the fix-ws-transport-global-registry branch from 5e30b16 to 3d940b8 Compare August 20, 2026 20:51

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fix(world-vercel): hold the ws channel registry on globalThis - #3699

fix(world-vercel): hold the ws channel registry on globalThis#3699
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fix-ws-transport-global-registry

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🧪 E2E Test Results

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💻 Local Development (4 failed)

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