Backport #3439: [core] Gate the unconsumed-event check on delivery idleness

[github-actions]

Automated backport of #3439 to stable (backport job run).

AI recommendation: This is a pure correctness fix (patch changeset) for a real defect that exists on stable: the unconsumed-event check's fixed DEFERRED_CHECK_DELAY_MS window races in-flight deliveries and raises a spurious ReplayDivergenceError, which escalates to CorruptedEventLogError and kills otherwise healthy runs. The touched files (packages/core/src/events-consumer.ts, private.ts, workflow.ts) all exist on stable with the same timing-bet logic, and the change adds only an internal predicate plus tests, no user-facing API or feature. Note that stable lacks the hasParkedCommittedDelivery/delivery-barrier machinery from #3183, so the cherry-pick will need adaptation and careful review.

Merge conflicts were resolved by AI (opencode with anthropic/claude-opus-5). Please review the conflict resolution carefully before merging.

[changeset-bot]

🦋 Changeset detected

Latest commit: 6233a82

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

This PR includes changesets to release 16 packages

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

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[vercel]

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Project	Deployment	Actions	Updated (UTC)
example-nextjs-workflow-turbopack	Ready	Preview	Aug 11, 2026 2:05am
example-nextjs-workflow-webpack	Ready	Preview	Aug 11, 2026 2:05am
example-workflow	Ready	Preview	Aug 11, 2026 2:05am
workbench-astro-workflow	Ready	Preview	Aug 11, 2026 2:05am
workbench-express-workflow	Ready	Preview	Aug 11, 2026 2:05am
workbench-fastify-workflow	Ready	Preview	Aug 11, 2026 2:05am
workbench-hono-workflow	Ready	Preview	Aug 11, 2026 2:05am
workbench-nestjs-workflow	Ready	Preview	Aug 11, 2026 2:05am
workbench-nitro-workflow	Ready	Preview	Aug 11, 2026 2:05am
workbench-nuxt-workflow	Ready	Preview	Aug 11, 2026 2:05am
workbench-python-workflow	Error		Aug 11, 2026 2:05am
workbench-sveltekit-workflow	Ready	Preview	Aug 11, 2026 2:05am
workbench-tanstack-start-workflow	Ready	Preview	Aug 11, 2026 2:05am
workbench-vite-workflow	Ready	Preview	Aug 11, 2026 2:05am
workflow-docs	Ready	Preview, v0	Aug 11, 2026 2:05am
workflow-swc-playground	Ready	Preview	Aug 11, 2026 2:05am
workflow-tarballs	Ready	Preview	Aug 11, 2026 2:05am
workflow-web	Ready	Preview	Aug 11, 2026 2:05am

[github-actions]

🧪 E2E Test Results

❌ Some tests failed

Summary

	Passed	Failed	Skipped	Total
✅ ▲ Vercel Production	1077	0	78	1155
✅ 💻 Local Development	1174	0	86	1260
✅ 📦 Local Production	1174	0	86	1260
✅ 🐘 Local Postgres	1174	0	86	1260
✅ 🪟 Windows	105	0	0	105
❌ 🌍 Community Worlds	83	101	9	193
✅ 📋 Other	594	0	36	630
Total	5381	101	381	5863

❌ Failed Tests

🌍 Community Worlds (101 failed)

redis (18 failed):

• hookWorkflow is not resumable via public webhook endpoint | wrun_01KZQ91099BNMFAV93QM7R9JE3
• parallelStepsThenWebhookWorkflow - no hook_conflict from same-tick replay race | wrun_01KZQ91AX9BNX430NDCJN3HFCR
• sleepingWorkflow | wrun_01KZQ928Z7PE25C6YGFSHFSPCV
• outputStreamWorkflow negative startIndex (reads from end)
• outputStreamWorkflow - getTailIndex and getStreamChunks getTailIndex returns correct index after stream completes
• outputStreamWorkflow - getTailIndex and getStreamChunks getTailIndex returns -1 before any chunks are written
• outputStreamWorkflow - getTailIndex and getStreamChunks getStreamChunks returns same content as reading the stream
• concurrent hook token conflict - two workflows cannot use the same hook token simultaneously | wrun_01KZQ99XW60JKF5HQR6B21RR0P
• hookGetConflictWorkflow - awaiting hook.getConflict() registers hook without payload | wrun_01KZQ9A9SDH5F834AT3FYZ055Z
• hookGetConflictThenStepParallelWorkflow - hook.getConflict() continuation step runs alongside other steps | wrun_01KZQ9AHM9FENG810P7BHGD4KX
• hookGetConflictWorkflow - hook.getConflict() resolves with the conflicting run when token is already registered | wrun_01KZQ9AZ1W52AQNA0NY5SQ14J4
• hookClaimOnlyMutexWorkflow - hook works as a pure run mutex without payload data | wrun_01KZQ9BSAEN47TCBEXX0G9D46G
• hookAdoptOwnerResultWorkflow - duplicate adopts the owner result via conflict.returnValue | wrun_01KZQ9BXRK5Z0Z1H68HTMYHQ7E
• hookSignalOwnerWorkflow - duplicate forwards its payload to the owner via resumeHook | wrun_01KZQ9C4045VG13BDRNM6ZW7M0
• hookSupersedeOwnerWorkflow - duplicate cancels the owner and claims the released token | wrun_01KZQ9C95JGT7MDH87ZFTCCFJ4
• resume-or-start route pattern - resumeHook retried after start() reaches the new run | wrun_01KZQ9CJ3D597EV6XYHZ8WC6Y7
• pages router sleepingWorkflow via pages router
• resilient start: addTenWorkflow completes when run_created returns 500 | wrun_01KZQ9HW5ME6E6J64JJG61FYG1

turso (83 failed):

• addTenWorkflow | wrun_01KZQ8ZVK0YF5SK4QG58P4VA47
• addTenWorkflow | wrun_01KZQ8ZVK0YF5SK4QG58P4VA47
• deploymentId: 'latest' is a no-op in non-Vercel worlds
• wellKnownAgentWorkflow (.well-known/agent) | wrun_01KZQ90BAKJMCHC42B4ZMHX8JH
• should work with react rendering in step
• promiseAllWorkflow | wrun_01KZQ9027VG9NKQAMBQ9HGPK2Z
• promiseRaceWorkflow | wrun_01KZQ906XDPXNCDYSWVY13YCBD
• promiseAnyWorkflow | wrun_01KZQ9099SEP0BKRKRTBRVEY67
• importedStepOnlyWorkflow | wrun_01KZQ90N6J21830V15CCSNJ0MK
• readableStreamWorkflow | wrun_01KZQ90BRWREBGXQVHS0W4VCCA
• hookWorkflow | wrun_01KZQ90R5BW5AWQYCAF1EFT9RW
• hookWorkflow is not resumable via public webhook endpoint | wrun_01KZQ91099BNMFAV93QM7R9JE3
• webhookWorkflow | wrun_01KZQ914NW9G09R0J9PS4Y8N97
• parallelStepsThenWebhookWorkflow - no hook_conflict from same-tick replay race | wrun_01KZQ91AX9BNX430NDCJN3HFCR
• sleepingWorkflow | wrun_01KZQ928Z7PE25C6YGFSHFSPCV
• parallelSleepWorkflow | wrun_01KZQ92RHNXZY1AB8RHF2KCWGB
• sleepWinsRaceWorkflow | wrun_01KZQ92W1TN7S79RYBS3YP53T9
• stepWinsRaceWorkflow | wrun_01KZQ92ZQ607662NR91285KHT0
• nullByteWorkflow | wrun_01KZQ9338X51SP18MDP3SR0RK6
• workflowAndStepMetadataWorkflow | wrun_01KZQ935KWR758HWGHTD476W9T
• outputStreamWorkflow no startIndex (reads all chunks)
• outputStreamWorkflow positive startIndex (skips first chunk)
• outputStreamWorkflow negative startIndex (reads from end)
• outputStreamWorkflow - getTailIndex and getStreamChunks getTailIndex returns correct index after stream completes
• outputStreamWorkflow - getTailIndex and getStreamChunks getTailIndex returns -1 before any chunks are written
• outputStreamWorkflow - getTailIndex and getStreamChunks getStreamChunks returns same content as reading the stream
• outputStreamInsideStepWorkflow - getWritable() called inside step functions | wrun_01KZQ95DZ4Y1A78TE27DHPGMF7
• writableForwardedFromWorkflowWorkflow | wrun_01KZQ95VTVA0TD163QE9K3DQB2
• writableForwardedFromStepWorkflow | wrun_01KZQ9609ARY2XY1WTMS7V6X1H
• fetchWorkflow | wrun_01KZQ963YC88701QHHVF5HG1PC
• promiseRaceStressTestWorkflow | wrun_01KZQ967DJBXSEKZ2FNGH1PH7Z
• error handling error propagation workflow errors nested function calls preserve message and stack trace
• error handling error propagation workflow errors cross-file imports preserve message and stack trace
• error handling error propagation step errors basic step error preserves message and stack trace
• error handling error propagation step errors cross-file step error preserves message and function names in stack
• error handling retry behavior regular Error retries until success
• error handling retry behavior FatalError fails immediately without retries
• error handling retry behavior RetryableError respects custom retryAfter delay
• error handling retry behavior maxRetries=0 disables retries
• error handling catchability FatalError can be caught and detected with FatalError.is()
• error handling not registered WorkflowNotRegisteredError fails the run when workflow does not exist
• error handling not registered StepNotRegisteredError fails the step but workflow can catch it
• error handling not registered StepNotRegisteredError fails the run when not caught in workflow
• hookCleanupTestWorkflow - hook token reuse after workflow completion | wrun_01KZQ99GQDTQ80FC487ZZ76S45
• concurrent hook token conflict - two workflows cannot use the same hook token simultaneously | wrun_01KZQ99XW60JKF5HQR6B21RR0P
• hookGetConflictWorkflow - awaiting hook.getConflict() registers hook without payload | wrun_01KZQ9A9SDH5F834AT3FYZ055Z
• 'hookGetConflictWithPriorStepWorkflow' - hook.getConflict() does not block step execution | wrun_01KZQ9ACCS140ZWGERK1J9GJ84
• 'hookGetConflictWithParallelStepWorkfl…' - hook.getConflict() does not block step execution | wrun_01KZQ9AEVTFJ4KFY92PT798EY3
• hookGetConflictThenStepParallelWorkflow - hook.getConflict() continuation step runs alongside other steps | wrun_01KZQ9AHM9FENG810P7BHGD4KX
• hookGetConflictWorkflow - hook.getConflict() resolves with the conflicting run when token is already registered | wrun_01KZQ9AZ1W52AQNA0NY5SQ14J4
• hookClaimOnlyMutexWorkflow - hook works as a pure run mutex without payload data | wrun_01KZQ9BSAEN47TCBEXX0G9D46G
• hookAdoptOwnerResultWorkflow - duplicate adopts the owner result via conflict.returnValue | wrun_01KZQ9BXRK5Z0Z1H68HTMYHQ7E
• hookSignalOwnerWorkflow - duplicate forwards its payload to the owner via resumeHook | wrun_01KZQ9C4045VG13BDRNM6ZW7M0
• hookSupersedeOwnerWorkflow - duplicate cancels the owner and claims the released token | wrun_01KZQ9C95JGT7MDH87ZFTCCFJ4
• resume-or-start route pattern - resumeHook retried after start() reaches the new run | wrun_01KZQ9CJ3D597EV6XYHZ8WC6Y7
• hookDisposeTestWorkflow - hook token reuse after explicit disposal while workflow still running | wrun_01KZQ9CS9HN2CY2NABW7NF94K6
• stepFunctionPassingWorkflow - step function references can be passed as arguments (without closure vars) | wrun_01KZQ9D8G3P1ZA7J0QB873G1XD
• stepFunctionWithClosureWorkflow - step function with closure variables passed as argument | wrun_01KZQ9DGXMASBNM8HFPB8KBF64
• closureVariableWorkflow - nested step functions with closure variables | wrun_01KZQ9DPB9HVMVFBAK37B7RY9F
• spawnWorkflowFromStepWorkflow - spawning a child workflow using start() inside a step | wrun_01KZQ9DRXWSCREPX17MPTQVJFJ
• health check (queue-based) - workflow and step endpoints respond to health check messages
• health check (CLI) - workflow health command reports healthy endpoints
• pathsAliasWorkflow - TypeScript path aliases resolve correctly | wrun_01KZQ9E7000PTYJ5D2KQHHBN9V
• Calculator.calculate - static workflow method using static step methods from another class | wrun_01KZQ9ECC3PQ9Z1XEWJ33H3JR8
• AllInOneService.processNumber - static workflow method using sibling static step methods | wrun_01KZQ9EHMSYP7RTFVPHK97150B
• ChainableService.processWithThis - static step methods using this to reference the class | wrun_01KZQ9EQ5R4F91VKX6P08785AJ
• thisSerializationWorkflow - step function invoked with .call() and .apply() | wrun_01KZQ9EXQ6J9PXMN0E31RG96AN
• customSerializationWorkflow - custom class serialization with WORKFLOW_SERIALIZE/WORKFLOW_DESERIALIZE | wrun_01KZQ9F4HVA67H3FD6HWY6FR05
• instanceMethodStepWorkflow - instance methods with "use step" directive | wrun_01KZQ9FB0S8YTQ8GG9C9A2MSDH
• crossContextSerdeWorkflow - classes defined in step code are deserializable in workflow context | wrun_01KZQ9FNZ2H0M3B1ZRQAYJCVZR
• stepFunctionAsStartArgWorkflow - step function reference passed as start() argument | wrun_01KZQ9FXY8TH8S58CX099PYQ9P
• cancelRun - cancelling a running workflow | wrun_01KZQ9G4F6PB565CK5A7DNBVGP
• cancelRun via CLI - cancelling a running workflow | wrun_01KZQ9G929255HPSH785M6RAVK
• pages router addTenWorkflow via pages router
• pages router promiseAllWorkflow via pages router
• pages router sleepingWorkflow via pages router
• hookWithSleepWorkflow - hook payloads delivered correctly with concurrent sleep | wrun_01KZQ9GFZ2YRBMQEZGFFDBBW68
• hookWithSleepFinalStepWorkflow - step only on final payload | wrun_01KZQ9GVZD93VACY6V5WZC8DZY
• sleepInLoopWorkflow - sleep inside loop with steps actually delays each iteration | wrun_01KZQ9H4G7KRCSG70ZER6EB1EP
• sleepWithSequentialStepsWorkflow - sequential steps work with concurrent sleep (control) | wrun_01KZQ9HFH6FZEW7T1MW55PAJGE
• importMetaUrlWorkflow - import.meta.url is available in step bundles | wrun_01KZQ9HQ8P79N7S04R6WJS4E8M
• metadataFromHelperWorkflow - getWorkflowMetadata/getStepMetadata work from module-level helper (#1577) | wrun_01KZQ9HSNPVN9VX2PSD8PB5084
• resilient start: addTenWorkflow completes when run_created returns 500 | wrun_01KZQ9HW5ME6E6J64JJG61FYG1

Details by Category

✅ ▲ Vercel Production

App	Passed	Failed	Skipped
✅ astro	97	0	8
✅ example	97	0	8
✅ express	97	0	8
✅ fastify	97	0	8
✅ hono	97	0	8
✅ nextjs-turbopack	102	0	3
✅ nextjs-webpack	102	0	3
✅ nitro	97	0	8
✅ nuxt	97	0	8
✅ sveltekit	97	0	8
✅ vite	97	0	8

✅ 💻 Local Development

App	Passed	Failed	Skipped
✅ astro-stable	99	0	6
✅ express-stable	99	0	6
✅ fastify-stable	99	0	6
✅ hono-stable	99	0	6
✅ nextjs-turbopack-canary	86	0	19
✅ nextjs-turbopack-stable	105	0	0
✅ nextjs-webpack-canary	86	0	19
✅ nextjs-webpack-stable	105	0	0
✅ nitro-stable	99	0	6
✅ nuxt-stable	99	0	6
✅ sveltekit-stable	99	0	6
✅ vite-stable	99	0	6

✅ 📦 Local Production

App	Passed	Failed	Skipped
✅ astro-stable	99	0	6
✅ express-stable	99	0	6
✅ fastify-stable	99	0	6
✅ hono-stable	99	0	6
✅ nextjs-turbopack-canary	86	0	19
✅ nextjs-turbopack-stable	105	0	0
✅ nextjs-webpack-canary	86	0	19
✅ nextjs-webpack-stable	105	0	0
✅ nitro-stable	99	0	6
✅ nuxt-stable	99	0	6
✅ sveltekit-stable	99	0	6
✅ vite-stable	99	0	6

✅ 🐘 Local Postgres

App	Passed	Failed	Skipped
✅ astro-stable	99	0	6
✅ express-stable	99	0	6
✅ fastify-stable	99	0	6
✅ hono-stable	99	0	6
✅ nextjs-turbopack-canary	86	0	19
✅ nextjs-turbopack-stable	105	0	0
✅ nextjs-webpack-canary	86	0	19
✅ nextjs-webpack-stable	105	0	0
✅ nitro-stable	99	0	6
✅ nuxt-stable	99	0	6
✅ sveltekit-stable	99	0	6
✅ vite-stable	99	0	6

✅ 🪟 Windows

App	Passed	Failed	Skipped
✅ nextjs-turbopack	105	0	0

❌ 🌍 Community Worlds

App	Passed	Failed	Skipped
✅ mongodb-dev	4	0	3
✅ redis-dev	4	0	3
❌ redis	68	18	0
✅ turso-dev	4	0	3
❌ turso	3	83	0

✅ 📋 Other

App	Passed	Failed	Skipped
✅ e2e-local-dev-nest-stable	99	0	6
✅ e2e-local-dev-tanstack-start-stable	99	0	6
✅ e2e-local-postgres-nest-stable	99	0	6
✅ e2e-local-postgres-tanstack-start-stable	99	0	6
✅ e2e-local-prod-nest-stable	99	0	6
✅ e2e-local-prod-tanstack-start-stable	99	0	6

---

📋 View full workflow run

[VaguelySerious]

(AI) Rebased onto current stable and resolved the conflict.

What caused it: the branch was cut when stable was at e822a6a173. Since then #3173 (backport of #3139) landed, which adds the delivery-barrier machinery to private.ts. The PR description's note that "stable lacks the hasParkedCommittedDelivery/delivery-barrier machinery" is now stale.

Resolution: because stable now has hasParkedCommittedDelivery and awaitEarlierDeliveries, the adaptation is no longer needed and the change converges on upstream. isDeliveryIdle / scheduleWhenIdle are now byte-identical to main:

export function isDeliveryIdle(ctx: WorkflowOrchestratorContext): boolean {
  return ctx.pendingDeliveries === 0 && !hasParkedCommittedDelivery(ctx);
}

The previous resolution had adapted this to pendingDeliveries === 0 alone. Keeping that would have been a regression: scheduleWhenIdle on stable checks pendingDeliveries > 0 || hasParkedCommittedDelivery(ctx), so routing it through a predicate that drops the second half would have silently reverted part of #3173. hasParkedCommittedDelivery stays unexported (nothing on stable imports it); the only other deviation from main is the two pre-existing stable gaps, no retained-session append() and no WORKFLOW_DEFERRED_CHECK_DELAY_MS override knob (envNumber does not exist in stable's world package), so the delay stays the DEFERRED_CHECK_DELAY_MS constant.

Validation: @workflow/core builds, typechecks, and all 836 src/ unit tests pass (the 6 e2e/ failures locally are the usual unbuilt-workbench/env-dependent ones).

Worth flagging for review: the shipped unconsumed-check-delivery-idle.test.ts only ever drives pendingDeliveries and leaves pendingDeliveryBarriers empty, so it passes under either version of the predicate. I wrote a throwaway test (not committed) that registers an armed step barrier with pendingDeliveries === 0, the parked-committed window from #3183. It fails 2/2 under the dropped-guard version and passes here. delivery-barrier-coverage.test.ts:536 also catches it, so CI would have gone red rather than merging the regression silently.

The workbench-python-workflow deployment failure is pre-existing: it fails on stable (6f301ba396) and on the previous PR head too.