[core] Prune schema modules from workflow bundles

[NathanColosimo]

Summary

• move runtime-only event metadata and attribute validation onto schema-free @workflow/world subpaths
• keep the public Zod schemas available to hosts without pulling them into the sandbox
• intentionally remove the superseded root-level World validation and event lookup exports as a v5 breaking change
• add regression coverage for both a minimal workflow and normal attribute, hook, and step APIs

Result

For the 97-step benchmark workflow:

• VM bundle: 612,980 B → 26,831 B (-95.6%)
• fresh-context evaluation p50: 10.536 ms → 0.121 ms (-98.9%)
• Zod modules in the benchmark VM bundle: 77 → 0 (workflows that import Zod themselves still include it)

Review scope

Serialized formats are unchanged. Besides the dependency-boundary refactor, this tightens two edge cases: an unknown attribute deletion can no longer offset a newly added key, and prototype-like event type strings safely return no metadata. The @workflow/world changeset is marked major for the intentionally removed public exports; on the current prerelease branch this still produces the next v5 beta.

Validation

• full workspace typecheck
• builders, core, world, and world-vercel package builds/typechecks
• 3,233 package tests across builders, core, world, and world-vercel
• focused workflow-bundle boundary regression tests
• Next/Turbopack and Vite production builds
• clean Codex + Claude autoreview after addressing feedback

[changeset-bot]

🦋 Changeset detected

Latest commit: 4834383

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

This PR includes changesets to release 20 packages

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

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Click here if you're a maintainer who wants to add another changeset to this PR

[vercel]

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

Project	Deployment	Actions	Updated (UTC)
example-nextjs-workflow-turbopack	Ready	Preview, v0	Aug 25, 2026 2:59am
example-nextjs-workflow-webpack	Ready	Preview, v0	Aug 25, 2026 2:59am
example-workflow	Ready	Preview, v0	Aug 25, 2026 2:59am
workbench-astro-workflow	Ready	Preview, v0	Aug 25, 2026 2:59am
workbench-express-workflow	Ready	Preview, v0	Aug 25, 2026 2:59am
workbench-fastify-workflow	Ready	Preview, v0	Aug 25, 2026 2:59am
workbench-hono-workflow	Ready	Preview, v0	Aug 25, 2026 2:59am
workbench-nestjs-workflow	Ready	Preview, v0	Aug 25, 2026 2:59am
workbench-nitro-workflow	Ready	Preview, v0	Aug 25, 2026 2:59am
workbench-nuxt-workflow	Ready	Preview, v0	Aug 25, 2026 2:59am
workbench-python-workflow	Ready	Preview, v0	Aug 25, 2026 2:59am
workbench-sveltekit-workflow	Ready	Preview, v0	Aug 25, 2026 2:59am
workbench-tanstack-start-workflow	Ready	Preview, v0	Aug 25, 2026 2:59am
workbench-vite-workflow	Ready	Preview, v0	Aug 25, 2026 2:59am
workflow-docs	Ready	Preview, v0	Aug 25, 2026 2:59am
workflow-swc-playground	Ready	Preview, v0	Aug 25, 2026 2:59am
workflow-tarballs	Ready	Preview, v0	Aug 25, 2026 2:59am
workflow-web	Ready	Preview, v0	Aug 25, 2026 2:59am

[github-actions]

🧪 E2E Test Results

❌ Some tests failed

❌ Failed E2E Tests

▲ Vercel Production (8 failed)

python-node (8 failed):

• promiseAllWorkflow | wrun_41M0VDN06C0GJF9R48YSG9WQ30 | 🔍 observability
• sleepingWorkflow | wrun_41M0VDNNN70GXQ8MQGB8DFFBVP | 🔍 observability
• parallelSleepWorkflow | wrun_41M0VDNQ4R0GTSQZ0NV78PS68F | 🔍 observability
• nullByteWorkflow | wrun_41M0VDNXQD0GN74C8N2SH970J4 | 🔍 observability
• cancelRun - cancelling a running workflow | wrun_41M0VDTG7Y0GKNVYEMFAZHAT66 | 🔍 observability
• cancelRun via CLI - cancelling a running workflow | wrun_41M0VDTH470GR3A7GYZW28QRRT | 🔍 observability
• sleepInLoopWorkflow - sleep inside loop with steps actually delays each iteration | wrun_41M0VDTWJP0GGDVNP9TXTDB25Y | 🔍 observability
• resilient start: addTenWorkflow completes when run_created returns 500 | wrun_41M0VDVECE0GW8TM4DBWV2H88X | 🔍 observability

🌐 Cross-language Conformance (9 failed)

python (9 failed):

• deploymentId: 'latest' is a no-op in non-Vercel worlds | wrun_01M0VDY8HAYKF5H611G7HRPJGV
• promiseAllWorkflow | wrun_41M0VDN06C0GJF9R48YSG9WQ30
• sleepingWorkflow | wrun_41M0VDNNN70GXQ8MQGB8DFFBVP
• parallelSleepWorkflow | wrun_41M0VDNQ4R0GTSQZ0NV78PS68F
• nullByteWorkflow | wrun_41M0VDNXQD0GN74C8N2SH970J4
• cancelRun - cancelling a running workflow | wrun_41M0VDTG7Y0GKNVYEMFAZHAT66
• cancelRun via CLI - cancelling a running workflow | wrun_41M0VDTH470GR3A7GYZW28QRRT
• sleepInLoopWorkflow - sleep inside loop with steps actually delays each iteration | wrun_41M0VDTWJP0GGDVNP9TXTDB25Y
• resilient start: addTenWorkflow completes when run_created returns 500 | wrun_41M0VDVECE0GW8TM4DBWV2H88X

⚠️ 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.

• cancelRun via CLI - cancelling a running workflow (nextjs-turbopack)
• hookGetConflictWorkflow - hook.getConflict() resolves with the conflicting run when token is already registered (express)

🛠 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.

34 infra events

• cold-start-warmup · suite warmup (python) · at 02:59:19Z · abandoned wrun_41M0VDKMMW0GH51Y8JG5NNFA53 · (+7 more)
• run-pickup-stall · sleepingWorkflow (python) · at 02:59:35Z · abandoned wrun_41M0VDQ9BQ0GQK2NWX2GHQEVNE
• run-pickup-stall · parallelSleepWorkflow (python) · at 02:59:35Z · abandoned wrun_41M0VDQ9BR0GJ9VX6F75YE9E9Q
• run-pickup-stall · nullByteWorkflow (python) · at 02:59:36Z · abandoned wrun_41M0VDQ9BV0GYFB5RFCSNMCKA8
• run-pickup-stall · promiseAllWorkflow (python) · at 02:59:36Z · abandoned wrun_41M0VDQ9BH0GK9EQXW0CP2ZJCA
• run-pickup-stall · cancelRun - cancelling a running workflow (python) · at 02:59:36Z · abandoned wrun_41M0VDQ9WK0GMVHTNXHTJD781E
• run-pickup-stall · cancelRun - cancelling a running workflow (python) · at 03:00:09Z · abandoned wrun_41M0VDR9R80GNBR3X3RRSVHN07
• run-pickup-stall · nullByteWorkflow (python) · at 03:00:36Z · abandoned wrun_41M0VDS4QY0GH9G06DD4CNPHN0
• run-pickup-stall · promiseAllWorkflow (python) · at 03:00:36Z · abandoned wrun_41M0VDS50Q0GX4S6T0PQTXW632
• run-pickup-stall · sleepingWorkflow (python) · at 03:00:36Z · abandoned wrun_41M0VDS50T0GSG4ZEE82KCJB3M
• run-pickup-stall · parallelSleepWorkflow (python) · at 03:00:36Z · abandoned wrun_41M0VDS4WM0GM7PK0RSWPBVGA0
• cold-start-warmup · suite warmup (tanstack-start) · at 03:00:41Z · abandoned wrun_01M0VDS3CBPAJR0ZH8W972WZZJ
• run-pickup-stall · cancelRun via CLI - cancelling a running workflow (python) · at 03:01:27Z · abandoned wrun_41M0VDS9XE0GTMQHS9QWWG5A2J
• cold-start-warmup · suite warmup (python) · at 03:01:53Z · abandoned wrun_01M0VDRA3CVH1MKDJEYP3V2BDW · (+7 more)
• run-pickup-stall · deploymentId: 'latest' is a no-op in non-Vercel worlds (python) · at 03:02:08Z · abandoned wrun_01M0VDVZ8CVJ5HP9G5FB1A1M3F
• run-pickup-stall · sleepingWorkflow (python) · at 03:02:08Z · abandoned wrun_01M0VDVZ8H5BFT2BTQGSX5M1FZ
• run-pickup-stall · parallelSleepWorkflow (python) · at 03:02:08Z · abandoned wrun_01M0VDVZ8M8XKZTWA23C6T2N7A
• run-pickup-stall · nullByteWorkflow (python) · at 03:02:08Z · abandoned wrun_01M0VDVZ8NTRCFXWR32772DDWJ
• run-pickup-stall · promiseAllWorkflow (python) · at 03:02:08Z · abandoned wrun_01M0VDVZ8DP1T84GQYSC3FST3V
• run-pickup-stall · workflow throws after awaited setAttributes: attribute still persists on the failed run (nuxt) · at 03:03:00Z · abandoned wrun_01M0VDXJ26475QRTXK3E4NYG5E
• run-pickup-stall · deploymentId: 'latest' is a no-op in non-Vercel worlds (python) · at 03:03:08Z · abandoned wrun_01M0VDXSW1STJBAFKY2ZTCJK9G
• run-pickup-stall · sleepingWorkflow (python) · at 03:03:08Z · abandoned wrun_01M0VDXSW5NENDADCH34B3A56A
• run-pickup-stall · promiseAllWorkflow (python) · at 03:03:08Z · abandoned wrun_01M0VDXSW3FS334GPAR9QK29DK
• run-pickup-stall · nullByteWorkflow (python) · at 03:03:08Z · abandoned wrun_01M0VDXSWE2XMMPSNBC595YAX9
• run-pickup-stall · parallelSleepWorkflow (python) · at 03:03:08Z · abandoned wrun_01M0VDXSW8ATGQPPHSTAPYGT45
• run-pickup-stall · cancelRun via CLI - cancelling a running workflow (python) · at 03:03:08Z · abandoned wrun_41M0VDW1SZ0GY2PX4NR4R4Y8X5
• run-pickup-stall · sleepInLoopWorkflow - sleep inside loop with steps actually delays each iteration (python) · at 03:03:08Z · abandoned wrun_41M0VDVWMG0GJ7M15MXRX9SJEM
• run-pickup-stall · cancelRun - cancelling a running workflow (python) · at 03:04:08Z · abandoned wrun_01M0VDZMFMRD0Y1PD7NBT2M72C
• run-pickup-stall · cancelRun via CLI - cancelling a running workflow (python) · at 03:04:08Z · abandoned wrun_01M0VDZMFVFN8Q4FA149CMQ9EQ
• run-pickup-stall · sleepInLoopWorkflow - sleep inside loop with steps actually delays each iteration (python) · at 03:04:08Z · abandoned wrun_01M0VDZMFZ1SM0TW62J5SAFBK3
• run-pickup-stall · cancelRun via CLI - cancelling a running workflow (python) · at 03:04:38Z · abandoned wrun_01M0VE0HVJRVGZC5NAGY22430N
• run-pickup-stall · cancelRun - cancelling a running workflow (python) · at 03:04:38Z · abandoned wrun_01M0VE0HVDHGJS57WFKR4Y7XDS
• run-pickup-stall · sleepInLoopWorkflow - sleep inside loop with steps actually delays each iteration (python) · at 03:05:08Z · abandoned wrun_01M0VE1F35J38MPSCFZMN6YX2P
• run-pickup-stall · WorkflowNotRegisteredError fails the run when workflow does not exist (nextjs-webpack) · at 03:05:16Z · abandoned wrun_01M0VE1QKFX8AWRVN1GKHDE0K9

E2E Test Summary

Summary

	Passed	Failed	Skipped	Total
❌ ▲ Vercel Production	3570	8	742	4320
✅ 💻 Local Development	3922	0	558	4480
✅ 📦 Local Production	3922	0	558	4480
✅ 🐘 Local Postgres	3922	0	558	4480
✅ 🪟 Windows	320	0	0	320
❌ 🌐 Cross-language Conformance	0	9	132	141
✅ vercel-http-transport	817	0	143	960
✅ vercel-multi-region	27	0	0	27
✅ vercel-ws-transport	553	0	87	640
Total	17053	17	2778	19848

Details by Category

❌ ▲ Vercel Production

App	Passed	Failed	Skipped
✅ astro-node	132	0	28
✅ astro-quickjs	132	0	28
✅ example-node	132	0	28
✅ example-quickjs	132	0	28
✅ express-node	132	0	28
✅ express-quickjs	132	0	28
✅ fastify-node	132	0	28
✅ fastify-quickjs	132	0	28
✅ hono-node	132	0	28
✅ hono-quickjs	132	0	28
✅ nest-node	132	0	28
✅ nest-quickjs	132	0	28
✅ nextjs-turbopack-node	157	0	3
✅ nextjs-turbopack-quickjs	157	0	3
✅ nextjs-webpack-node	157	0	3
✅ nextjs-webpack-quickjs	157	0	3
✅ nitro-node	132	0	28
✅ nitro-quickjs	132	0	28
✅ nuxt-node	132	0	28
✅ nuxt-quickjs	132	0	28
❌ python-node	0	8	152
✅ sveltekit-node	151	0	9
✅ sveltekit-quickjs	151	0	9
✅ tanstack-start-node	132	0	28
✅ tanstack-start-quickjs	132	0	28
✅ vite-node	132	0	28
✅ vite-quickjs	132	0	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	141	0	19
✅ nextjs-webpack-canary-quickjs	141	0	19
✅ nextjs-webpack-stable-node	160	0	0
✅ nextjs-webpack-stable-quickjs	160	0	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	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	141	0	19
✅ nextjs-webpack-canary-quickjs	141	0	19
✅ nextjs-webpack-stable-node	160	0	0
✅ nextjs-webpack-stable-quickjs	160	0	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 Postgres

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	141	0	19
✅ nextjs-webpack-canary-quickjs	141	0	19
✅ nextjs-webpack-stable-node	160	0	0
✅ nextjs-webpack-stable-quickjs	160	0	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

✅ 🪟 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	0	9	132

✅ vercel-http-transport

App	Passed	Failed	Skipped
✅ example	132	0	28
✅ express	132	0	28
✅ hono	132	0	28
✅ nextjs-turbopack	157	0	3
✅ nitro	132	0	28
✅ vite	132	0	28

✅ vercel-multi-region

App	Passed	Failed	Skipped
✅ nextjs-turbopack	27	0	0

✅ vercel-ws-transport

App	Passed	Failed	Skipped
✅ example	132	0	28
✅ express	132	0	28
✅ nextjs-turbopack	157	0	3
✅ vite	132	0	28

---

📋 View full workflow run

[github-actions]

📊 Workflow Benchmarks

commit 4834383 · Tue, 25 Aug 2026 03:22:33 GMT · run logs

Backend: vercel · app: nextjs-turbopack

Metric	Scenario	Best (ms)	P75 (ms)	P90 (ms)	P99 (ms)	Samples
TTFS	step	240 (-38%) 💚	1525 🔴 (+39%) 🔻	1574 🔴 (+39%) 🔻	1838 🔴 (+32%) 🔻	30
TTFS	stream	485 (+177%) 🔻	1484 🔴 (+34%) 🔻	1516 🔴 (+34%) 🔻	1567 🔴 (+36%) 🔻	30
TTFS	hook + stream	1712 (+199%) 🔻	1839 🔴 (+35%) 🔻	1897 🔴 (+20%) 🔻	1990 🔴 (-57%) 💚	30
Fan-out TTFS	Promise.all(100 steps)	640 (+2.2%)	2135 (+95%) 🔻	2156 (+39%) 🔻	2292 (-54%) 💚	10
Fan-out TTLS	Promise.all(100 steps)	2612 (+44%) 🔻	4012 (±0%)	4044 (-0.7%)	10348 (+3.9%)	10
STSO	1020 steps (inline)	100 (-11%)	156 (+9.1%)	175 (+5.4%)	281 (+17%) 🔻	1019
WO	1020 steps	157552 (+8.3%)	157552 (+8.3%)	157552 (+8.3%)	157552 (+8.3%)	1
CRTT	first chunk (pooled)	125 (+51%) 🔻	198 (+41%) 🔻	246 (-5.4%)	458 (-35%) 💚	28

Streams

Scenario	CRTT 1st	p75	p90	p99	CDV max	iters
paced control (100/s, 60B)	154 (+38%)	192 (+27%)	257 (-30%)	390 (-42%)	162 (+33%)	10
size sweep (100/s, 160B-12KB)	147 (+31%)	197 (+55%)	323 (+99%)	1023 (+56%)	228 (+111%)	10
replay gateway-gpt-5.4-nano-2000t (1x)	182 (+2%)	146 (-77%)	176 (-92%)	303 (-92%)	211 (-46%)	3
replay eve-gpt-5.6-sol-2000t (1x)	206 (+49%)	163 (+16%)	216 (+14%)	379 (-26%)	221 (-56%)	2
replay eve-gpt-5.6-sol-2000t (2x)	167 (+18%)	208 (+11%)	286 (+6%)	673 (-19%)	290 (+60%)	3

📈 STSO distribution vs main (inline / queue-hop histograms)

1020 steps (inline)

Cumulative STSO time: main 144386ms → this run 156134ms (Δ +11748ms, +8%)

100-150 ms █████████████████┃██████ main 853 this 646 -207
150-200 ms ████░░░░┃ main 138 this 336 +198
200-250 ms ┃ main 19 this 22 +3
250-300 ms ┃ main 4 this 7 +3
300-350 ms ┃ main 5 this 3 -2
350-400 ms ┃ main 0 this 2 +2
400-450 ms ┃ main 0 this 2 +2
600-650 ms ┃ main 0 this 1 +1

📈 CRTT drill-down vs main (RTT distributions & profiles)

variant RTT 1ms→5s+ avg p50 p90 p99 n
control ······▂█▂···· 150.5 (+19%) 135 (+27%) 257 (-30%) 390 (-42%) 3000
sweep ······▂█▂▁▁·· 172.3 (+46%) 145 (+46%) 323 (+99%) 1023 (+56%) 3000
gw 1x ······▃█▁···· 129 (-56%) 125 (+2%) 176 (-92%) 303 (-92%) 5295
eve 1x ······▃█▂···· 138.3 (+14%) 125 (+23%) 216 (+14%) 379 (-26%) 5186
eve 2x ······▁█▃▁··· 171.6 (+16%) 156 (+16%) 286 (+6%) 673 (-19%) 7779

RTT over stream progress (avg per tenth of stream, bars scaled min→max):

control █▇▄▃▂▃▃▁▁▁ 130–189ms
sweep ▃██▅▃▂▁▂▁▂ 133–242ms
gw 1x ▅▄▄█▄▃▂▂▃▁ 120–144ms
eve 1x ▆▂▁▃▁▁██▂▃ 124–166ms
eve 2x ▄▁▃▂▂▆▃▅▆█ 145–207ms

RTT by chunk size (avg per log size bin, ~160B → ~12KB serialized, bars scaled min→max):

sweep █▄▄▄▃▁▄ 170–175ms

Delivery jitter over stream progress (avg positive CDV per tenth of stream, bars scaled min→max):

control ▁▅▃█▄█▄▂▂▁ 40–50ms
sweep ▁▆▅▄▃▆▄▆▃█ 48–65ms
gw 1x ▄▆▃▁▅▂▅█▁▃ 38–43ms
eve 1x ▇▄▁▄▃▃▆▃▂█ 23–32ms
eve 2x █▇▁▂▆▅▄▁▃▆ 24–33ms

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.}

_{The collapsed STSO distribution section above buckets every step gap, split inline (same warm process — pure framework overhead) vs queue-hop (fresh process — dispatch, reinit, replay). █ = main, ┃ = this run, ░ = fill.}

_{The collapsed CRTT drill-down: per-variant RTT histograms (fixed log bins, · = empty) and mean RTT/positive-CDV profile lines over stream progress and chunk size. Histograms, avgs, and profiles merge exactly across runs; p50–p99 are percentile-of-percentiles. Per-index rows live in the artifacts.}

_{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-2000teaf22f5946e7c61f3c65c7006d550df180cfabd4e706254a09f22aec0cfb420d · gateway-gpt-5.4-nano-2000t6f24ac518b6b83ff1d0e85a5fe78230db192716d66a7fc6b2fe022752001d041}

_{🔴 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.}

[VaguelySerious]

AI review: no blocking issues

[TooTallNate]

AI: Approved. I found no blocking issues in the schema-free module split, validation changes, package exports, or bundle-boundary coverage.

[github-actions]

No backport to stable for d62b444 (AI decision).

This is primarily a bundle-size/startup-performance refactor that moves World validation and event-metadata helpers onto new @workflow/world subpath exports and intentionally removes public root-level exports (validateAttributeKey, validateAttributeValue, EVENT_DATA_PAYLOAD_FIELD_BY_EVENT_TYPE, EVENT_DATA_REF_FIELDS) as a deliberate v5 breaking change, carrying a major changeset — exactly the kind of API-surface churn a maintenance line should not take. The two genuine hardening bits (an unknown attribute deletion no longer offsetting a newly added key in the per-run cap accounting in validateAttributeChanges, and prototype-like event type strings such as constructor returning no metadata) are small and could be split out and force-backported on their own if desired. Per the mixed-commit rule, the presence of a breaking refactor makes the whole commit ineligible.

To override, re-run the Backport to stable workflow manually via workflow_dispatch and paste this commit SHA into the ref input:

d62b44473b43e183e71386fe84b33f5e7bb5445c

[NathanColosimo]

Summary

• move runtime-only event metadata and attribute validation onto schema-free @workflow/world subpaths
• keep the public Zod schemas available to hosts without pulling them into the sandbox
• intentionally remove the superseded root-level World validation and event lookup exports as a v5 breaking change
• add regression coverage for both a minimal workflow and normal attribute, hook, and step APIs

Result

For the 97-step benchmark workflow:

• VM bundle: 612,980 B → 26,831 B (-95.6%)
• fresh-context evaluation p50: 10.536 ms → 0.121 ms (-98.9%)
• Zod modules in the benchmark VM bundle: 77 → 0 (workflows that import Zod themselves still include it)

Review scope

Serialized formats are unchanged. Besides the dependency-boundary refactor, this tightens two edge cases: an unknown attribute deletion can no longer offset a newly added key, and prototype-like event type strings safely return no metadata. The @workflow/world changeset is marked major for the intentionally removed public exports; on the current prerelease branch this still produces the next v5 beta.

Validation

• full workspace typecheck
• builders, core, world, and world-vercel package builds/typechecks
• 3,233 package tests across builders, core, world, and world-vercel
• focused workflow-bundle boundary regression tests
• Next/Turbopack and Vite production builds
• clean Codex + Claude autoreview after addressing feedback

[changeset-bot]

🦋 Changeset detected

Latest commit: 4834383

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

This PR includes changesets to release 20 packages

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

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

Project	Deployment	Actions	Updated (UTC)
example-nextjs-workflow-turbopack	Ready	Preview, v0	Aug 25, 2026 2:59am
example-nextjs-workflow-webpack	Ready	Preview, v0	Aug 25, 2026 2:59am
example-workflow	Ready	Preview, v0	Aug 25, 2026 2:59am
workbench-astro-workflow	Ready	Preview, v0	Aug 25, 2026 2:59am
workbench-express-workflow	Ready	Preview, v0	Aug 25, 2026 2:59am
workbench-fastify-workflow	Ready	Preview, v0	Aug 25, 2026 2:59am
workbench-hono-workflow	Ready	Preview, v0	Aug 25, 2026 2:59am
workbench-nestjs-workflow	Ready	Preview, v0	Aug 25, 2026 2:59am
workbench-nitro-workflow	Ready	Preview, v0	Aug 25, 2026 2:59am
workbench-nuxt-workflow	Ready	Preview, v0	Aug 25, 2026 2:59am
workbench-python-workflow	Ready	Preview, v0	Aug 25, 2026 2:59am
workbench-sveltekit-workflow	Ready	Preview, v0	Aug 25, 2026 2:59am
workbench-tanstack-start-workflow	Ready	Preview, v0	Aug 25, 2026 2:59am
workbench-vite-workflow	Ready	Preview, v0	Aug 25, 2026 2:59am
workflow-docs	Ready	Preview, v0	Aug 25, 2026 2:59am
workflow-swc-playground	Ready	Preview, v0	Aug 25, 2026 2:59am
workflow-tarballs	Ready	Preview, v0	Aug 25, 2026 2:59am
workflow-web	Ready	Preview, v0	Aug 25, 2026 2:59am

[github-actions]

🧪 E2E Test Results

❌ Some tests failed

❌ Failed E2E Tests

▲ Vercel Production (8 failed)

python-node (8 failed):

• promiseAllWorkflow | wrun_41M0VDN06C0GJF9R48YSG9WQ30 | 🔍 observability
• sleepingWorkflow | wrun_41M0VDNNN70GXQ8MQGB8DFFBVP | 🔍 observability
• parallelSleepWorkflow | wrun_41M0VDNQ4R0GTSQZ0NV78PS68F | 🔍 observability
• nullByteWorkflow | wrun_41M0VDNXQD0GN74C8N2SH970J4 | 🔍 observability
• cancelRun - cancelling a running workflow | wrun_41M0VDTG7Y0GKNVYEMFAZHAT66 | 🔍 observability
• cancelRun via CLI - cancelling a running workflow | wrun_41M0VDTH470GR3A7GYZW28QRRT | 🔍 observability
• sleepInLoopWorkflow - sleep inside loop with steps actually delays each iteration | wrun_41M0VDTWJP0GGDVNP9TXTDB25Y | 🔍 observability
• resilient start: addTenWorkflow completes when run_created returns 500 | wrun_41M0VDVECE0GW8TM4DBWV2H88X | 🔍 observability

🌐 Cross-language Conformance (9 failed)

python (9 failed):

• deploymentId: 'latest' is a no-op in non-Vercel worlds | wrun_01M0VDY8HAYKF5H611G7HRPJGV
• promiseAllWorkflow | wrun_41M0VDN06C0GJF9R48YSG9WQ30
• sleepingWorkflow | wrun_41M0VDNNN70GXQ8MQGB8DFFBVP
• parallelSleepWorkflow | wrun_41M0VDNQ4R0GTSQZ0NV78PS68F
• nullByteWorkflow | wrun_41M0VDNXQD0GN74C8N2SH970J4
• cancelRun - cancelling a running workflow | wrun_41M0VDTG7Y0GKNVYEMFAZHAT66
• cancelRun via CLI - cancelling a running workflow | wrun_41M0VDTH470GR3A7GYZW28QRRT
• sleepInLoopWorkflow - sleep inside loop with steps actually delays each iteration | wrun_41M0VDTWJP0GGDVNP9TXTDB25Y
• resilient start: addTenWorkflow completes when run_created returns 500 | wrun_41M0VDVECE0GW8TM4DBWV2H88X

⚠️ 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.

• cancelRun via CLI - cancelling a running workflow (nextjs-turbopack)
• hookGetConflictWorkflow - hook.getConflict() resolves with the conflicting run when token is already registered (express)

🛠 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.

34 infra events

• cold-start-warmup · suite warmup (python) · at 02:59:19Z · abandoned wrun_41M0VDKMMW0GH51Y8JG5NNFA53 · (+7 more)
• run-pickup-stall · sleepingWorkflow (python) · at 02:59:35Z · abandoned wrun_41M0VDQ9BQ0GQK2NWX2GHQEVNE
• run-pickup-stall · parallelSleepWorkflow (python) · at 02:59:35Z · abandoned wrun_41M0VDQ9BR0GJ9VX6F75YE9E9Q
• run-pickup-stall · nullByteWorkflow (python) · at 02:59:36Z · abandoned wrun_41M0VDQ9BV0GYFB5RFCSNMCKA8
• run-pickup-stall · promiseAllWorkflow (python) · at 02:59:36Z · abandoned wrun_41M0VDQ9BH0GK9EQXW0CP2ZJCA
• run-pickup-stall · cancelRun - cancelling a running workflow (python) · at 02:59:36Z · abandoned wrun_41M0VDQ9WK0GMVHTNXHTJD781E
• run-pickup-stall · cancelRun - cancelling a running workflow (python) · at 03:00:09Z · abandoned wrun_41M0VDR9R80GNBR3X3RRSVHN07
• run-pickup-stall · nullByteWorkflow (python) · at 03:00:36Z · abandoned wrun_41M0VDS4QY0GH9G06DD4CNPHN0
• run-pickup-stall · promiseAllWorkflow (python) · at 03:00:36Z · abandoned wrun_41M0VDS50Q0GX4S6T0PQTXW632
• run-pickup-stall · sleepingWorkflow (python) · at 03:00:36Z · abandoned wrun_41M0VDS50T0GSG4ZEE82KCJB3M
• run-pickup-stall · parallelSleepWorkflow (python) · at 03:00:36Z · abandoned wrun_41M0VDS4WM0GM7PK0RSWPBVGA0
• cold-start-warmup · suite warmup (tanstack-start) · at 03:00:41Z · abandoned wrun_01M0VDS3CBPAJR0ZH8W972WZZJ
• run-pickup-stall · cancelRun via CLI - cancelling a running workflow (python) · at 03:01:27Z · abandoned wrun_41M0VDS9XE0GTMQHS9QWWG5A2J
• cold-start-warmup · suite warmup (python) · at 03:01:53Z · abandoned wrun_01M0VDRA3CVH1MKDJEYP3V2BDW · (+7 more)
• run-pickup-stall · deploymentId: 'latest' is a no-op in non-Vercel worlds (python) · at 03:02:08Z · abandoned wrun_01M0VDVZ8CVJ5HP9G5FB1A1M3F
• run-pickup-stall · sleepingWorkflow (python) · at 03:02:08Z · abandoned wrun_01M0VDVZ8H5BFT2BTQGSX5M1FZ
• run-pickup-stall · parallelSleepWorkflow (python) · at 03:02:08Z · abandoned wrun_01M0VDVZ8M8XKZTWA23C6T2N7A
• run-pickup-stall · nullByteWorkflow (python) · at 03:02:08Z · abandoned wrun_01M0VDVZ8NTRCFXWR32772DDWJ
• run-pickup-stall · promiseAllWorkflow (python) · at 03:02:08Z · abandoned wrun_01M0VDVZ8DP1T84GQYSC3FST3V
• run-pickup-stall · workflow throws after awaited setAttributes: attribute still persists on the failed run (nuxt) · at 03:03:00Z · abandoned wrun_01M0VDXJ26475QRTXK3E4NYG5E
• run-pickup-stall · deploymentId: 'latest' is a no-op in non-Vercel worlds (python) · at 03:03:08Z · abandoned wrun_01M0VDXSW1STJBAFKY2ZTCJK9G
• run-pickup-stall · sleepingWorkflow (python) · at 03:03:08Z · abandoned wrun_01M0VDXSW5NENDADCH34B3A56A
• run-pickup-stall · promiseAllWorkflow (python) · at 03:03:08Z · abandoned wrun_01M0VDXSW3FS334GPAR9QK29DK
• run-pickup-stall · nullByteWorkflow (python) · at 03:03:08Z · abandoned wrun_01M0VDXSWE2XMMPSNBC595YAX9
• run-pickup-stall · parallelSleepWorkflow (python) · at 03:03:08Z · abandoned wrun_01M0VDXSW8ATGQPPHSTAPYGT45
• run-pickup-stall · cancelRun via CLI - cancelling a running workflow (python) · at 03:03:08Z · abandoned wrun_41M0VDW1SZ0GY2PX4NR4R4Y8X5
• run-pickup-stall · sleepInLoopWorkflow - sleep inside loop with steps actually delays each iteration (python) · at 03:03:08Z · abandoned wrun_41M0VDVWMG0GJ7M15MXRX9SJEM
• run-pickup-stall · cancelRun - cancelling a running workflow (python) · at 03:04:08Z · abandoned wrun_01M0VDZMFMRD0Y1PD7NBT2M72C
• run-pickup-stall · cancelRun via CLI - cancelling a running workflow (python) · at 03:04:08Z · abandoned wrun_01M0VDZMFVFN8Q4FA149CMQ9EQ
• run-pickup-stall · sleepInLoopWorkflow - sleep inside loop with steps actually delays each iteration (python) · at 03:04:08Z · abandoned wrun_01M0VDZMFZ1SM0TW62J5SAFBK3
• run-pickup-stall · cancelRun via CLI - cancelling a running workflow (python) · at 03:04:38Z · abandoned wrun_01M0VE0HVJRVGZC5NAGY22430N
• run-pickup-stall · cancelRun - cancelling a running workflow (python) · at 03:04:38Z · abandoned wrun_01M0VE0HVDHGJS57WFKR4Y7XDS
• run-pickup-stall · sleepInLoopWorkflow - sleep inside loop with steps actually delays each iteration (python) · at 03:05:08Z · abandoned wrun_01M0VE1F35J38MPSCFZMN6YX2P
• run-pickup-stall · WorkflowNotRegisteredError fails the run when workflow does not exist (nextjs-webpack) · at 03:05:16Z · abandoned wrun_01M0VE1QKFX8AWRVN1GKHDE0K9

E2E Test Summary

Summary

	Passed	Failed	Skipped	Total
❌ ▲ Vercel Production	3570	8	742	4320
✅ 💻 Local Development	3922	0	558	4480
✅ 📦 Local Production	3922	0	558	4480
✅ 🐘 Local Postgres	3922	0	558	4480
✅ 🪟 Windows	320	0	0	320
❌ 🌐 Cross-language Conformance	0	9	132	141
✅ vercel-http-transport	817	0	143	960
✅ vercel-multi-region	27	0	0	27
✅ vercel-ws-transport	553	0	87	640
Total	17053	17	2778	19848

Details by Category

❌ ▲ Vercel Production

App	Passed	Failed	Skipped
✅ astro-node	132	0	28
✅ astro-quickjs	132	0	28
✅ example-node	132	0	28
✅ example-quickjs	132	0	28
✅ express-node	132	0	28
✅ express-quickjs	132	0	28
✅ fastify-node	132	0	28
✅ fastify-quickjs	132	0	28
✅ hono-node	132	0	28
✅ hono-quickjs	132	0	28
✅ nest-node	132	0	28
✅ nest-quickjs	132	0	28
✅ nextjs-turbopack-node	157	0	3
✅ nextjs-turbopack-quickjs	157	0	3
✅ nextjs-webpack-node	157	0	3
✅ nextjs-webpack-quickjs	157	0	3
✅ nitro-node	132	0	28
✅ nitro-quickjs	132	0	28
✅ nuxt-node	132	0	28
✅ nuxt-quickjs	132	0	28
❌ python-node	0	8	152
✅ sveltekit-node	151	0	9
✅ sveltekit-quickjs	151	0	9
✅ tanstack-start-node	132	0	28
✅ tanstack-start-quickjs	132	0	28
✅ vite-node	132	0	28
✅ vite-quickjs	132	0	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	141	0	19
✅ nextjs-webpack-canary-quickjs	141	0	19
✅ nextjs-webpack-stable-node	160	0	0
✅ nextjs-webpack-stable-quickjs	160	0	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	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	141	0	19
✅ nextjs-webpack-canary-quickjs	141	0	19
✅ nextjs-webpack-stable-node	160	0	0
✅ nextjs-webpack-stable-quickjs	160	0	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 Postgres

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	141	0	19
✅ nextjs-webpack-canary-quickjs	141	0	19
✅ nextjs-webpack-stable-node	160	0	0
✅ nextjs-webpack-stable-quickjs	160	0	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

✅ 🪟 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	0	9	132

✅ vercel-http-transport

App	Passed	Failed	Skipped
✅ example	132	0	28
✅ express	132	0	28
✅ hono	132	0	28
✅ nextjs-turbopack	157	0	3
✅ nitro	132	0	28
✅ vite	132	0	28

✅ vercel-multi-region

App	Passed	Failed	Skipped
✅ nextjs-turbopack	27	0	0

✅ vercel-ws-transport

App	Passed	Failed	Skipped
✅ example	132	0	28
✅ express	132	0	28
✅ nextjs-turbopack	157	0	3
✅ vite	132	0	28

---

📋 View full workflow run

[github-actions]

📊 Workflow Benchmarks

commit 4834383 · Tue, 25 Aug 2026 03:22:33 GMT · run logs

Backend: vercel · app: nextjs-turbopack

Metric	Scenario	Best (ms)	P75 (ms)	P90 (ms)	P99 (ms)	Samples
TTFS	step	240 (-38%) 💚	1525 🔴 (+39%) 🔻	1574 🔴 (+39%) 🔻	1838 🔴 (+32%) 🔻	30
TTFS	stream	485 (+177%) 🔻	1484 🔴 (+34%) 🔻	1516 🔴 (+34%) 🔻	1567 🔴 (+36%) 🔻	30
TTFS	hook + stream	1712 (+199%) 🔻	1839 🔴 (+35%) 🔻	1897 🔴 (+20%) 🔻	1990 🔴 (-57%) 💚	30
Fan-out TTFS	Promise.all(100 steps)	640 (+2.2%)	2135 (+95%) 🔻	2156 (+39%) 🔻	2292 (-54%) 💚	10
Fan-out TTLS	Promise.all(100 steps)	2612 (+44%) 🔻	4012 (±0%)	4044 (-0.7%)	10348 (+3.9%)	10
STSO	1020 steps (inline)	100 (-11%)	156 (+9.1%)	175 (+5.4%)	281 (+17%) 🔻	1019
WO	1020 steps	157552 (+8.3%)	157552 (+8.3%)	157552 (+8.3%)	157552 (+8.3%)	1
CRTT	first chunk (pooled)	125 (+51%) 🔻	198 (+41%) 🔻	246 (-5.4%)	458 (-35%) 💚	28

Streams

Scenario	CRTT 1st	p75	p90	p99	CDV max	iters
paced control (100/s, 60B)	154 (+38%)	192 (+27%)	257 (-30%)	390 (-42%)	162 (+33%)	10
size sweep (100/s, 160B-12KB)	147 (+31%)	197 (+55%)	323 (+99%)	1023 (+56%)	228 (+111%)	10
replay gateway-gpt-5.4-nano-2000t (1x)	182 (+2%)	146 (-77%)	176 (-92%)	303 (-92%)	211 (-46%)	3
replay eve-gpt-5.6-sol-2000t (1x)	206 (+49%)	163 (+16%)	216 (+14%)	379 (-26%)	221 (-56%)	2
replay eve-gpt-5.6-sol-2000t (2x)	167 (+18%)	208 (+11%)	286 (+6%)	673 (-19%)	290 (+60%)	3

📈 STSO distribution vs main (inline / queue-hop histograms)

1020 steps (inline)

Cumulative STSO time: main 144386ms → this run 156134ms (Δ +11748ms, +8%)

100-150 ms █████████████████┃██████ main 853 this 646 -207
150-200 ms ████░░░░┃ main 138 this 336 +198
200-250 ms ┃ main 19 this 22 +3
250-300 ms ┃ main 4 this 7 +3
300-350 ms ┃ main 5 this 3 -2
350-400 ms ┃ main 0 this 2 +2
400-450 ms ┃ main 0 this 2 +2
600-650 ms ┃ main 0 this 1 +1

📈 CRTT drill-down vs main (RTT distributions & profiles)

variant RTT 1ms→5s+ avg p50 p90 p99 n
control ······▂█▂···· 150.5 (+19%) 135 (+27%) 257 (-30%) 390 (-42%) 3000
sweep ······▂█▂▁▁·· 172.3 (+46%) 145 (+46%) 323 (+99%) 1023 (+56%) 3000
gw 1x ······▃█▁···· 129 (-56%) 125 (+2%) 176 (-92%) 303 (-92%) 5295
eve 1x ······▃█▂···· 138.3 (+14%) 125 (+23%) 216 (+14%) 379 (-26%) 5186
eve 2x ······▁█▃▁··· 171.6 (+16%) 156 (+16%) 286 (+6%) 673 (-19%) 7779

RTT over stream progress (avg per tenth of stream, bars scaled min→max):

control █▇▄▃▂▃▃▁▁▁ 130–189ms
sweep ▃██▅▃▂▁▂▁▂ 133–242ms
gw 1x ▅▄▄█▄▃▂▂▃▁ 120–144ms
eve 1x ▆▂▁▃▁▁██▂▃ 124–166ms
eve 2x ▄▁▃▂▂▆▃▅▆█ 145–207ms

RTT by chunk size (avg per log size bin, ~160B → ~12KB serialized, bars scaled min→max):

sweep █▄▄▄▃▁▄ 170–175ms

Delivery jitter over stream progress (avg positive CDV per tenth of stream, bars scaled min→max):

control ▁▅▃█▄█▄▂▂▁ 40–50ms
sweep ▁▆▅▄▃▆▄▆▃█ 48–65ms
gw 1x ▄▆▃▁▅▂▅█▁▃ 38–43ms
eve 1x ▇▄▁▄▃▃▆▃▂█ 23–32ms
eve 2x █▇▁▂▆▅▄▁▃▆ 24–33ms

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.}

_{The collapsed STSO distribution section above buckets every step gap, split inline (same warm process — pure framework overhead) vs queue-hop (fresh process — dispatch, reinit, replay). █ = main, ┃ = this run, ░ = fill.}

_{The collapsed CRTT drill-down: per-variant RTT histograms (fixed log bins, · = empty) and mean RTT/positive-CDV profile lines over stream progress and chunk size. Histograms, avgs, and profiles merge exactly across runs; p50–p99 are percentile-of-percentiles. Per-index rows live in the artifacts.}

_{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-2000teaf22f5946e7c61f3c65c7006d550df180cfabd4e706254a09f22aec0cfb420d · gateway-gpt-5.4-nano-2000t6f24ac518b6b83ff1d0e85a5fe78230db192716d66a7fc6b2fe022752001d041}

_{🔴 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.}

[VaguelySerious]

AI review: no blocking issues

[TooTallNate]

AI: Approved. I found no blocking issues in the schema-free module split, validation changes, package exports, or bundle-boundary coverage.

[github-actions]

No backport to stable for d62b444 (AI decision).

This is primarily a bundle-size/startup-performance refactor that moves World validation and event-metadata helpers onto new @workflow/world subpath exports and intentionally removes public root-level exports (validateAttributeKey, validateAttributeValue, EVENT_DATA_PAYLOAD_FIELD_BY_EVENT_TYPE, EVENT_DATA_REF_FIELDS) as a deliberate v5 breaking change, carrying a major changeset — exactly the kind of API-surface churn a maintenance line should not take. The two genuine hardening bits (an unknown attribute deletion no longer offsetting a newly added key in the per-run cap accounting in validateAttributeChanges, and prototype-like event type strings such as constructor returning no metadata) are small and could be split out and force-backported on their own if desired. Per the mixed-commit rule, the presence of a breaking refactor makes the whole commit ineligible.

To override, re-run the Backport to stable workflow manually via workflow_dispatch and paste this commit SHA into the ref input:

d62b44473b43e183e71386fe84b33f5e7bb5445c

[NathanColosimo]

Summary

• move runtime-only event metadata and attribute validation onto schema-free @workflow/world subpaths
• keep the public Zod schemas available to hosts without pulling them into the sandbox
• intentionally remove the superseded root-level World validation and event lookup exports as a v5 breaking change
• add regression coverage for both a minimal workflow and normal attribute, hook, and step APIs

Result

For the 97-step benchmark workflow:

• VM bundle: 612,980 B → 26,831 B (-95.6%)
• fresh-context evaluation p50: 10.536 ms → 0.121 ms (-98.9%)
• Zod modules in the benchmark VM bundle: 77 → 0 (workflows that import Zod themselves still include it)

Review scope

Serialized formats are unchanged. Besides the dependency-boundary refactor, this tightens two edge cases: an unknown attribute deletion can no longer offset a newly added key, and prototype-like event type strings safely return no metadata. The @workflow/world changeset is marked major for the intentionally removed public exports; on the current prerelease branch this still produces the next v5 beta.

Validation

• full workspace typecheck
• builders, core, world, and world-vercel package builds/typechecks
• 3,233 package tests across builders, core, world, and world-vercel
• focused workflow-bundle boundary regression tests
• Next/Turbopack and Vite production builds
• clean Codex + Claude autoreview after addressing feedback

[changeset-bot]

🦋 Changeset detected

Latest commit: 4834383

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

This PR includes changesets to release 20 packages

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

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

Project	Deployment	Actions	Updated (UTC)
example-nextjs-workflow-turbopack	Ready	Preview, v0	Aug 25, 2026 2:59am
example-nextjs-workflow-webpack	Ready	Preview, v0	Aug 25, 2026 2:59am
example-workflow	Ready	Preview, v0	Aug 25, 2026 2:59am
workbench-astro-workflow	Ready	Preview, v0	Aug 25, 2026 2:59am
workbench-express-workflow	Ready	Preview, v0	Aug 25, 2026 2:59am
workbench-fastify-workflow	Ready	Preview, v0	Aug 25, 2026 2:59am
workbench-hono-workflow	Ready	Preview, v0	Aug 25, 2026 2:59am
workbench-nestjs-workflow	Ready	Preview, v0	Aug 25, 2026 2:59am
workbench-nitro-workflow	Ready	Preview, v0	Aug 25, 2026 2:59am
workbench-nuxt-workflow	Ready	Preview, v0	Aug 25, 2026 2:59am
workbench-python-workflow	Ready	Preview, v0	Aug 25, 2026 2:59am
workbench-sveltekit-workflow	Ready	Preview, v0	Aug 25, 2026 2:59am
workbench-tanstack-start-workflow	Ready	Preview, v0	Aug 25, 2026 2:59am
workbench-vite-workflow	Ready	Preview, v0	Aug 25, 2026 2:59am
workflow-docs	Ready	Preview, v0	Aug 25, 2026 2:59am
workflow-swc-playground	Ready	Preview, v0	Aug 25, 2026 2:59am
workflow-tarballs	Ready	Preview, v0	Aug 25, 2026 2:59am
workflow-web	Ready	Preview, v0	Aug 25, 2026 2:59am

[github-actions]

🧪 E2E Test Results

❌ Some tests failed

❌ Failed E2E Tests

▲ Vercel Production (8 failed)

python-node (8 failed):

• promiseAllWorkflow | wrun_41M0VDN06C0GJF9R48YSG9WQ30 | 🔍 observability
• sleepingWorkflow | wrun_41M0VDNNN70GXQ8MQGB8DFFBVP | 🔍 observability
• parallelSleepWorkflow | wrun_41M0VDNQ4R0GTSQZ0NV78PS68F | 🔍 observability
• nullByteWorkflow | wrun_41M0VDNXQD0GN74C8N2SH970J4 | 🔍 observability
• cancelRun - cancelling a running workflow | wrun_41M0VDTG7Y0GKNVYEMFAZHAT66 | 🔍 observability
• cancelRun via CLI - cancelling a running workflow | wrun_41M0VDTH470GR3A7GYZW28QRRT | 🔍 observability
• sleepInLoopWorkflow - sleep inside loop with steps actually delays each iteration | wrun_41M0VDTWJP0GGDVNP9TXTDB25Y | 🔍 observability
• resilient start: addTenWorkflow completes when run_created returns 500 | wrun_41M0VDVECE0GW8TM4DBWV2H88X | 🔍 observability

🌐 Cross-language Conformance (9 failed)

python (9 failed):

• deploymentId: 'latest' is a no-op in non-Vercel worlds | wrun_01M0VDY8HAYKF5H611G7HRPJGV
• promiseAllWorkflow | wrun_41M0VDN06C0GJF9R48YSG9WQ30
• sleepingWorkflow | wrun_41M0VDNNN70GXQ8MQGB8DFFBVP
• parallelSleepWorkflow | wrun_41M0VDNQ4R0GTSQZ0NV78PS68F
• nullByteWorkflow | wrun_41M0VDNXQD0GN74C8N2SH970J4
• cancelRun - cancelling a running workflow | wrun_41M0VDTG7Y0GKNVYEMFAZHAT66
• cancelRun via CLI - cancelling a running workflow | wrun_41M0VDTH470GR3A7GYZW28QRRT
• sleepInLoopWorkflow - sleep inside loop with steps actually delays each iteration | wrun_41M0VDTWJP0GGDVNP9TXTDB25Y
• resilient start: addTenWorkflow completes when run_created returns 500 | wrun_41M0VDVECE0GW8TM4DBWV2H88X

⚠️ 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.

• cancelRun via CLI - cancelling a running workflow (nextjs-turbopack)
• hookGetConflictWorkflow - hook.getConflict() resolves with the conflicting run when token is already registered (express)

🛠 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.

34 infra events

• cold-start-warmup · suite warmup (python) · at 02:59:19Z · abandoned wrun_41M0VDKMMW0GH51Y8JG5NNFA53 · (+7 more)
• run-pickup-stall · sleepingWorkflow (python) · at 02:59:35Z · abandoned wrun_41M0VDQ9BQ0GQK2NWX2GHQEVNE
• run-pickup-stall · parallelSleepWorkflow (python) · at 02:59:35Z · abandoned wrun_41M0VDQ9BR0GJ9VX6F75YE9E9Q
• run-pickup-stall · nullByteWorkflow (python) · at 02:59:36Z · abandoned wrun_41M0VDQ9BV0GYFB5RFCSNMCKA8
• run-pickup-stall · promiseAllWorkflow (python) · at 02:59:36Z · abandoned wrun_41M0VDQ9BH0GK9EQXW0CP2ZJCA
• run-pickup-stall · cancelRun - cancelling a running workflow (python) · at 02:59:36Z · abandoned wrun_41M0VDQ9WK0GMVHTNXHTJD781E
• run-pickup-stall · cancelRun - cancelling a running workflow (python) · at 03:00:09Z · abandoned wrun_41M0VDR9R80GNBR3X3RRSVHN07
• run-pickup-stall · nullByteWorkflow (python) · at 03:00:36Z · abandoned wrun_41M0VDS4QY0GH9G06DD4CNPHN0
• run-pickup-stall · promiseAllWorkflow (python) · at 03:00:36Z · abandoned wrun_41M0VDS50Q0GX4S6T0PQTXW632
• run-pickup-stall · sleepingWorkflow (python) · at 03:00:36Z · abandoned wrun_41M0VDS50T0GSG4ZEE82KCJB3M
• run-pickup-stall · parallelSleepWorkflow (python) · at 03:00:36Z · abandoned wrun_41M0VDS4WM0GM7PK0RSWPBVGA0
• cold-start-warmup · suite warmup (tanstack-start) · at 03:00:41Z · abandoned wrun_01M0VDS3CBPAJR0ZH8W972WZZJ
• run-pickup-stall · cancelRun via CLI - cancelling a running workflow (python) · at 03:01:27Z · abandoned wrun_41M0VDS9XE0GTMQHS9QWWG5A2J
• cold-start-warmup · suite warmup (python) · at 03:01:53Z · abandoned wrun_01M0VDRA3CVH1MKDJEYP3V2BDW · (+7 more)
• run-pickup-stall · deploymentId: 'latest' is a no-op in non-Vercel worlds (python) · at 03:02:08Z · abandoned wrun_01M0VDVZ8CVJ5HP9G5FB1A1M3F
• run-pickup-stall · sleepingWorkflow (python) · at 03:02:08Z · abandoned wrun_01M0VDVZ8H5BFT2BTQGSX5M1FZ
• run-pickup-stall · parallelSleepWorkflow (python) · at 03:02:08Z · abandoned wrun_01M0VDVZ8M8XKZTWA23C6T2N7A
• run-pickup-stall · nullByteWorkflow (python) · at 03:02:08Z · abandoned wrun_01M0VDVZ8NTRCFXWR32772DDWJ
• run-pickup-stall · promiseAllWorkflow (python) · at 03:02:08Z · abandoned wrun_01M0VDVZ8DP1T84GQYSC3FST3V
• run-pickup-stall · workflow throws after awaited setAttributes: attribute still persists on the failed run (nuxt) · at 03:03:00Z · abandoned wrun_01M0VDXJ26475QRTXK3E4NYG5E
• run-pickup-stall · deploymentId: 'latest' is a no-op in non-Vercel worlds (python) · at 03:03:08Z · abandoned wrun_01M0VDXSW1STJBAFKY2ZTCJK9G
• run-pickup-stall · sleepingWorkflow (python) · at 03:03:08Z · abandoned wrun_01M0VDXSW5NENDADCH34B3A56A
• run-pickup-stall · promiseAllWorkflow (python) · at 03:03:08Z · abandoned wrun_01M0VDXSW3FS334GPAR9QK29DK
• run-pickup-stall · nullByteWorkflow (python) · at 03:03:08Z · abandoned wrun_01M0VDXSWE2XMMPSNBC595YAX9
• run-pickup-stall · parallelSleepWorkflow (python) · at 03:03:08Z · abandoned wrun_01M0VDXSW8ATGQPPHSTAPYGT45
• run-pickup-stall · cancelRun via CLI - cancelling a running workflow (python) · at 03:03:08Z · abandoned wrun_41M0VDW1SZ0GY2PX4NR4R4Y8X5
• run-pickup-stall · sleepInLoopWorkflow - sleep inside loop with steps actually delays each iteration (python) · at 03:03:08Z · abandoned wrun_41M0VDVWMG0GJ7M15MXRX9SJEM
• run-pickup-stall · cancelRun - cancelling a running workflow (python) · at 03:04:08Z · abandoned wrun_01M0VDZMFMRD0Y1PD7NBT2M72C
• run-pickup-stall · cancelRun via CLI - cancelling a running workflow (python) · at 03:04:08Z · abandoned wrun_01M0VDZMFVFN8Q4FA149CMQ9EQ
• run-pickup-stall · sleepInLoopWorkflow - sleep inside loop with steps actually delays each iteration (python) · at 03:04:08Z · abandoned wrun_01M0VDZMFZ1SM0TW62J5SAFBK3
• run-pickup-stall · cancelRun via CLI - cancelling a running workflow (python) · at 03:04:38Z · abandoned wrun_01M0VE0HVJRVGZC5NAGY22430N
• run-pickup-stall · cancelRun - cancelling a running workflow (python) · at 03:04:38Z · abandoned wrun_01M0VE0HVDHGJS57WFKR4Y7XDS
• run-pickup-stall · sleepInLoopWorkflow - sleep inside loop with steps actually delays each iteration (python) · at 03:05:08Z · abandoned wrun_01M0VE1F35J38MPSCFZMN6YX2P
• run-pickup-stall · WorkflowNotRegisteredError fails the run when workflow does not exist (nextjs-webpack) · at 03:05:16Z · abandoned wrun_01M0VE1QKFX8AWRVN1GKHDE0K9

E2E Test Summary

Summary

	Passed	Failed	Skipped	Total
❌ ▲ Vercel Production	3570	8	742	4320
✅ 💻 Local Development	3922	0	558	4480
✅ 📦 Local Production	3922	0	558	4480
✅ 🐘 Local Postgres	3922	0	558	4480
✅ 🪟 Windows	320	0	0	320
❌ 🌐 Cross-language Conformance	0	9	132	141
✅ vercel-http-transport	817	0	143	960
✅ vercel-multi-region	27	0	0	27
✅ vercel-ws-transport	553	0	87	640
Total	17053	17	2778	19848

Details by Category

❌ ▲ Vercel Production

App	Passed	Failed	Skipped
✅ astro-node	132	0	28
✅ astro-quickjs	132	0	28
✅ example-node	132	0	28
✅ example-quickjs	132	0	28
✅ express-node	132	0	28
✅ express-quickjs	132	0	28
✅ fastify-node	132	0	28
✅ fastify-quickjs	132	0	28
✅ hono-node	132	0	28
✅ hono-quickjs	132	0	28
✅ nest-node	132	0	28
✅ nest-quickjs	132	0	28
✅ nextjs-turbopack-node	157	0	3
✅ nextjs-turbopack-quickjs	157	0	3
✅ nextjs-webpack-node	157	0	3
✅ nextjs-webpack-quickjs	157	0	3
✅ nitro-node	132	0	28
✅ nitro-quickjs	132	0	28
✅ nuxt-node	132	0	28
✅ nuxt-quickjs	132	0	28
❌ python-node	0	8	152
✅ sveltekit-node	151	0	9
✅ sveltekit-quickjs	151	0	9
✅ tanstack-start-node	132	0	28
✅ tanstack-start-quickjs	132	0	28
✅ vite-node	132	0	28
✅ vite-quickjs	132	0	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	141	0	19
✅ nextjs-webpack-canary-quickjs	141	0	19
✅ nextjs-webpack-stable-node	160	0	0
✅ nextjs-webpack-stable-quickjs	160	0	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	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	141	0	19
✅ nextjs-webpack-canary-quickjs	141	0	19
✅ nextjs-webpack-stable-node	160	0	0
✅ nextjs-webpack-stable-quickjs	160	0	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 Postgres

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	141	0	19
✅ nextjs-webpack-canary-quickjs	141	0	19
✅ nextjs-webpack-stable-node	160	0	0
✅ nextjs-webpack-stable-quickjs	160	0	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

✅ 🪟 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	0	9	132

✅ vercel-http-transport

App	Passed	Failed	Skipped
✅ example	132	0	28
✅ express	132	0	28
✅ hono	132	0	28
✅ nextjs-turbopack	157	0	3
✅ nitro	132	0	28
✅ vite	132	0	28

✅ vercel-multi-region

App	Passed	Failed	Skipped
✅ nextjs-turbopack	27	0	0

✅ vercel-ws-transport

App	Passed	Failed	Skipped
✅ example	132	0	28
✅ express	132	0	28
✅ nextjs-turbopack	157	0	3
✅ vite	132	0	28

---

📋 View full workflow run

[github-actions]

📊 Workflow Benchmarks

commit 4834383 · Tue, 25 Aug 2026 03:22:33 GMT · run logs

Backend: vercel · app: nextjs-turbopack

Metric	Scenario	Best (ms)	P75 (ms)	P90 (ms)	P99 (ms)	Samples
TTFS	step	240 (-38%) 💚	1525 🔴 (+39%) 🔻	1574 🔴 (+39%) 🔻	1838 🔴 (+32%) 🔻	30
TTFS	stream	485 (+177%) 🔻	1484 🔴 (+34%) 🔻	1516 🔴 (+34%) 🔻	1567 🔴 (+36%) 🔻	30
TTFS	hook + stream	1712 (+199%) 🔻	1839 🔴 (+35%) 🔻	1897 🔴 (+20%) 🔻	1990 🔴 (-57%) 💚	30
Fan-out TTFS	Promise.all(100 steps)	640 (+2.2%)	2135 (+95%) 🔻	2156 (+39%) 🔻	2292 (-54%) 💚	10
Fan-out TTLS	Promise.all(100 steps)	2612 (+44%) 🔻	4012 (±0%)	4044 (-0.7%)	10348 (+3.9%)	10
STSO	1020 steps (inline)	100 (-11%)	156 (+9.1%)	175 (+5.4%)	281 (+17%) 🔻	1019
WO	1020 steps	157552 (+8.3%)	157552 (+8.3%)	157552 (+8.3%)	157552 (+8.3%)	1
CRTT	first chunk (pooled)	125 (+51%) 🔻	198 (+41%) 🔻	246 (-5.4%)	458 (-35%) 💚	28

Streams

Scenario	CRTT 1st	p75	p90	p99	CDV max	iters
paced control (100/s, 60B)	154 (+38%)	192 (+27%)	257 (-30%)	390 (-42%)	162 (+33%)	10
size sweep (100/s, 160B-12KB)	147 (+31%)	197 (+55%)	323 (+99%)	1023 (+56%)	228 (+111%)	10
replay gateway-gpt-5.4-nano-2000t (1x)	182 (+2%)	146 (-77%)	176 (-92%)	303 (-92%)	211 (-46%)	3
replay eve-gpt-5.6-sol-2000t (1x)	206 (+49%)	163 (+16%)	216 (+14%)	379 (-26%)	221 (-56%)	2
replay eve-gpt-5.6-sol-2000t (2x)	167 (+18%)	208 (+11%)	286 (+6%)	673 (-19%)	290 (+60%)	3

📈 STSO distribution vs main (inline / queue-hop histograms)

1020 steps (inline)

Cumulative STSO time: main 144386ms → this run 156134ms (Δ +11748ms, +8%)

100-150 ms █████████████████┃██████ main 853 this 646 -207
150-200 ms ████░░░░┃ main 138 this 336 +198
200-250 ms ┃ main 19 this 22 +3
250-300 ms ┃ main 4 this 7 +3
300-350 ms ┃ main 5 this 3 -2
350-400 ms ┃ main 0 this 2 +2
400-450 ms ┃ main 0 this 2 +2
600-650 ms ┃ main 0 this 1 +1

📈 CRTT drill-down vs main (RTT distributions & profiles)

variant RTT 1ms→5s+ avg p50 p90 p99 n
control ······▂█▂···· 150.5 (+19%) 135 (+27%) 257 (-30%) 390 (-42%) 3000
sweep ······▂█▂▁▁·· 172.3 (+46%) 145 (+46%) 323 (+99%) 1023 (+56%) 3000
gw 1x ······▃█▁···· 129 (-56%) 125 (+2%) 176 (-92%) 303 (-92%) 5295
eve 1x ······▃█▂···· 138.3 (+14%) 125 (+23%) 216 (+14%) 379 (-26%) 5186
eve 2x ······▁█▃▁··· 171.6 (+16%) 156 (+16%) 286 (+6%) 673 (-19%) 7779

RTT over stream progress (avg per tenth of stream, bars scaled min→max):

control █▇▄▃▂▃▃▁▁▁ 130–189ms
sweep ▃██▅▃▂▁▂▁▂ 133–242ms
gw 1x ▅▄▄█▄▃▂▂▃▁ 120–144ms
eve 1x ▆▂▁▃▁▁██▂▃ 124–166ms
eve 2x ▄▁▃▂▂▆▃▅▆█ 145–207ms

RTT by chunk size (avg per log size bin, ~160B → ~12KB serialized, bars scaled min→max):

sweep █▄▄▄▃▁▄ 170–175ms

Delivery jitter over stream progress (avg positive CDV per tenth of stream, bars scaled min→max):

control ▁▅▃█▄█▄▂▂▁ 40–50ms
sweep ▁▆▅▄▃▆▄▆▃█ 48–65ms
gw 1x ▄▆▃▁▅▂▅█▁▃ 38–43ms
eve 1x ▇▄▁▄▃▃▆▃▂█ 23–32ms
eve 2x █▇▁▂▆▅▄▁▃▆ 24–33ms

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.}

_{The collapsed STSO distribution section above buckets every step gap, split inline (same warm process — pure framework overhead) vs queue-hop (fresh process — dispatch, reinit, replay). █ = main, ┃ = this run, ░ = fill.}

_{The collapsed CRTT drill-down: per-variant RTT histograms (fixed log bins, · = empty) and mean RTT/positive-CDV profile lines over stream progress and chunk size. Histograms, avgs, and profiles merge exactly across runs; p50–p99 are percentile-of-percentiles. Per-index rows live in the artifacts.}

_{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-2000teaf22f5946e7c61f3c65c7006d550df180cfabd4e706254a09f22aec0cfb420d · gateway-gpt-5.4-nano-2000t6f24ac518b6b83ff1d0e85a5fe78230db192716d66a7fc6b2fe022752001d041}

_{🔴 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.}

[VaguelySerious]

AI review: no blocking issues

[TooTallNate]

AI: Approved. I found no blocking issues in the schema-free module split, validation changes, package exports, or bundle-boundary coverage.

[github-actions]

No backport to stable for d62b444 (AI decision).

This is primarily a bundle-size/startup-performance refactor that moves World validation and event-metadata helpers onto new @workflow/world subpath exports and intentionally removes public root-level exports (validateAttributeKey, validateAttributeValue, EVENT_DATA_PAYLOAD_FIELD_BY_EVENT_TYPE, EVENT_DATA_REF_FIELDS) as a deliberate v5 breaking change, carrying a major changeset — exactly the kind of API-surface churn a maintenance line should not take. The two genuine hardening bits (an unknown attribute deletion no longer offsetting a newly added key in the per-run cap accounting in validateAttributeChanges, and prototype-like event type strings such as constructor returning no metadata) are small and could be split out and force-backported on their own if desired. Per the mixed-commit rule, the presence of a breaking refactor makes the whole commit ineligible.

To override, re-run the Backport to stable workflow manually via workflow_dispatch and paste this commit SHA into the ref input:

d62b44473b43e183e71386fe84b33f5e7bb5445c

[NathanColosimo]

Summary

• move runtime-only event metadata and attribute validation onto schema-free @workflow/world subpaths
• keep the public Zod schemas available to hosts without pulling them into the sandbox
• intentionally remove the superseded root-level World validation and event lookup exports as a v5 breaking change
• add regression coverage for both a minimal workflow and normal attribute, hook, and step APIs

Result

For the 97-step benchmark workflow:

• VM bundle: 612,980 B → 26,831 B (-95.6%)
• fresh-context evaluation p50: 10.536 ms → 0.121 ms (-98.9%)
• Zod modules in the benchmark VM bundle: 77 → 0 (workflows that import Zod themselves still include it)

Review scope

Serialized formats are unchanged. Besides the dependency-boundary refactor, this tightens two edge cases: an unknown attribute deletion can no longer offset a newly added key, and prototype-like event type strings safely return no metadata. The @workflow/world changeset is marked major for the intentionally removed public exports; on the current prerelease branch this still produces the next v5 beta.

Validation

• full workspace typecheck
• builders, core, world, and world-vercel package builds/typechecks
• 3,233 package tests across builders, core, world, and world-vercel
• focused workflow-bundle boundary regression tests
• Next/Turbopack and Vite production builds
• clean Codex + Claude autoreview after addressing feedback

[changeset-bot]

🦋 Changeset detected

Latest commit: 4834383

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

This PR includes changesets to release 20 packages

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

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

Project	Deployment	Actions	Updated (UTC)
example-nextjs-workflow-turbopack	Ready	Preview, v0	Aug 25, 2026 2:59am
example-nextjs-workflow-webpack	Ready	Preview, v0	Aug 25, 2026 2:59am
example-workflow	Ready	Preview, v0	Aug 25, 2026 2:59am
workbench-astro-workflow	Ready	Preview, v0	Aug 25, 2026 2:59am
workbench-express-workflow	Ready	Preview, v0	Aug 25, 2026 2:59am
workbench-fastify-workflow	Ready	Preview, v0	Aug 25, 2026 2:59am
workbench-hono-workflow	Ready	Preview, v0	Aug 25, 2026 2:59am
workbench-nestjs-workflow	Ready	Preview, v0	Aug 25, 2026 2:59am
workbench-nitro-workflow	Ready	Preview, v0	Aug 25, 2026 2:59am
workbench-nuxt-workflow	Ready	Preview, v0	Aug 25, 2026 2:59am
workbench-python-workflow	Ready	Preview, v0	Aug 25, 2026 2:59am
workbench-sveltekit-workflow	Ready	Preview, v0	Aug 25, 2026 2:59am
workbench-tanstack-start-workflow	Ready	Preview, v0	Aug 25, 2026 2:59am
workbench-vite-workflow	Ready	Preview, v0	Aug 25, 2026 2:59am
workflow-docs	Ready	Preview, v0	Aug 25, 2026 2:59am
workflow-swc-playground	Ready	Preview, v0	Aug 25, 2026 2:59am
workflow-tarballs	Ready	Preview, v0	Aug 25, 2026 2:59am
workflow-web	Ready	Preview, v0	Aug 25, 2026 2:59am

[github-actions]

🧪 E2E Test Results

❌ Some tests failed

❌ Failed E2E Tests

▲ Vercel Production (8 failed)

python-node (8 failed):

• promiseAllWorkflow | wrun_41M0VDN06C0GJF9R48YSG9WQ30 | 🔍 observability
• sleepingWorkflow | wrun_41M0VDNNN70GXQ8MQGB8DFFBVP | 🔍 observability
• parallelSleepWorkflow | wrun_41M0VDNQ4R0GTSQZ0NV78PS68F | 🔍 observability
• nullByteWorkflow | wrun_41M0VDNXQD0GN74C8N2SH970J4 | 🔍 observability
• cancelRun - cancelling a running workflow | wrun_41M0VDTG7Y0GKNVYEMFAZHAT66 | 🔍 observability
• cancelRun via CLI - cancelling a running workflow | wrun_41M0VDTH470GR3A7GYZW28QRRT | 🔍 observability
• sleepInLoopWorkflow - sleep inside loop with steps actually delays each iteration | wrun_41M0VDTWJP0GGDVNP9TXTDB25Y | 🔍 observability
• resilient start: addTenWorkflow completes when run_created returns 500 | wrun_41M0VDVECE0GW8TM4DBWV2H88X | 🔍 observability

🌐 Cross-language Conformance (9 failed)

python (9 failed):

• deploymentId: 'latest' is a no-op in non-Vercel worlds | wrun_01M0VDY8HAYKF5H611G7HRPJGV
• promiseAllWorkflow | wrun_41M0VDN06C0GJF9R48YSG9WQ30
• sleepingWorkflow | wrun_41M0VDNNN70GXQ8MQGB8DFFBVP
• parallelSleepWorkflow | wrun_41M0VDNQ4R0GTSQZ0NV78PS68F
• nullByteWorkflow | wrun_41M0VDNXQD0GN74C8N2SH970J4
• cancelRun - cancelling a running workflow | wrun_41M0VDTG7Y0GKNVYEMFAZHAT66
• cancelRun via CLI - cancelling a running workflow | wrun_41M0VDTH470GR3A7GYZW28QRRT
• sleepInLoopWorkflow - sleep inside loop with steps actually delays each iteration | wrun_41M0VDTWJP0GGDVNP9TXTDB25Y
• resilient start: addTenWorkflow completes when run_created returns 500 | wrun_41M0VDVECE0GW8TM4DBWV2H88X

⚠️ 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.

• cancelRun via CLI - cancelling a running workflow (nextjs-turbopack)
• hookGetConflictWorkflow - hook.getConflict() resolves with the conflicting run when token is already registered (express)

🛠 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.

34 infra events

• cold-start-warmup · suite warmup (python) · at 02:59:19Z · abandoned wrun_41M0VDKMMW0GH51Y8JG5NNFA53 · (+7 more)
• run-pickup-stall · sleepingWorkflow (python) · at 02:59:35Z · abandoned wrun_41M0VDQ9BQ0GQK2NWX2GHQEVNE
• run-pickup-stall · parallelSleepWorkflow (python) · at 02:59:35Z · abandoned wrun_41M0VDQ9BR0GJ9VX6F75YE9E9Q
• run-pickup-stall · nullByteWorkflow (python) · at 02:59:36Z · abandoned wrun_41M0VDQ9BV0GYFB5RFCSNMCKA8
• run-pickup-stall · promiseAllWorkflow (python) · at 02:59:36Z · abandoned wrun_41M0VDQ9BH0GK9EQXW0CP2ZJCA
• run-pickup-stall · cancelRun - cancelling a running workflow (python) · at 02:59:36Z · abandoned wrun_41M0VDQ9WK0GMVHTNXHTJD781E
• run-pickup-stall · cancelRun - cancelling a running workflow (python) · at 03:00:09Z · abandoned wrun_41M0VDR9R80GNBR3X3RRSVHN07
• run-pickup-stall · nullByteWorkflow (python) · at 03:00:36Z · abandoned wrun_41M0VDS4QY0GH9G06DD4CNPHN0
• run-pickup-stall · promiseAllWorkflow (python) · at 03:00:36Z · abandoned wrun_41M0VDS50Q0GX4S6T0PQTXW632
• run-pickup-stall · sleepingWorkflow (python) · at 03:00:36Z · abandoned wrun_41M0VDS50T0GSG4ZEE82KCJB3M
• run-pickup-stall · parallelSleepWorkflow (python) · at 03:00:36Z · abandoned wrun_41M0VDS4WM0GM7PK0RSWPBVGA0
• cold-start-warmup · suite warmup (tanstack-start) · at 03:00:41Z · abandoned wrun_01M0VDS3CBPAJR0ZH8W972WZZJ
• run-pickup-stall · cancelRun via CLI - cancelling a running workflow (python) · at 03:01:27Z · abandoned wrun_41M0VDS9XE0GTMQHS9QWWG5A2J
• cold-start-warmup · suite warmup (python) · at 03:01:53Z · abandoned wrun_01M0VDRA3CVH1MKDJEYP3V2BDW · (+7 more)
• run-pickup-stall · deploymentId: 'latest' is a no-op in non-Vercel worlds (python) · at 03:02:08Z · abandoned wrun_01M0VDVZ8CVJ5HP9G5FB1A1M3F
• run-pickup-stall · sleepingWorkflow (python) · at 03:02:08Z · abandoned wrun_01M0VDVZ8H5BFT2BTQGSX5M1FZ
• run-pickup-stall · parallelSleepWorkflow (python) · at 03:02:08Z · abandoned wrun_01M0VDVZ8M8XKZTWA23C6T2N7A
• run-pickup-stall · nullByteWorkflow (python) · at 03:02:08Z · abandoned wrun_01M0VDVZ8NTRCFXWR32772DDWJ
• run-pickup-stall · promiseAllWorkflow (python) · at 03:02:08Z · abandoned wrun_01M0VDVZ8DP1T84GQYSC3FST3V
• run-pickup-stall · workflow throws after awaited setAttributes: attribute still persists on the failed run (nuxt) · at 03:03:00Z · abandoned wrun_01M0VDXJ26475QRTXK3E4NYG5E
• run-pickup-stall · deploymentId: 'latest' is a no-op in non-Vercel worlds (python) · at 03:03:08Z · abandoned wrun_01M0VDXSW1STJBAFKY2ZTCJK9G
• run-pickup-stall · sleepingWorkflow (python) · at 03:03:08Z · abandoned wrun_01M0VDXSW5NENDADCH34B3A56A
• run-pickup-stall · promiseAllWorkflow (python) · at 03:03:08Z · abandoned wrun_01M0VDXSW3FS334GPAR9QK29DK
• run-pickup-stall · nullByteWorkflow (python) · at 03:03:08Z · abandoned wrun_01M0VDXSWE2XMMPSNBC595YAX9
• run-pickup-stall · parallelSleepWorkflow (python) · at 03:03:08Z · abandoned wrun_01M0VDXSW8ATGQPPHSTAPYGT45
• run-pickup-stall · cancelRun via CLI - cancelling a running workflow (python) · at 03:03:08Z · abandoned wrun_41M0VDW1SZ0GY2PX4NR4R4Y8X5
• run-pickup-stall · sleepInLoopWorkflow - sleep inside loop with steps actually delays each iteration (python) · at 03:03:08Z · abandoned wrun_41M0VDVWMG0GJ7M15MXRX9SJEM
• run-pickup-stall · cancelRun - cancelling a running workflow (python) · at 03:04:08Z · abandoned wrun_01M0VDZMFMRD0Y1PD7NBT2M72C
• run-pickup-stall · cancelRun via CLI - cancelling a running workflow (python) · at 03:04:08Z · abandoned wrun_01M0VDZMFVFN8Q4FA149CMQ9EQ
• run-pickup-stall · sleepInLoopWorkflow - sleep inside loop with steps actually delays each iteration (python) · at 03:04:08Z · abandoned wrun_01M0VDZMFZ1SM0TW62J5SAFBK3
• run-pickup-stall · cancelRun via CLI - cancelling a running workflow (python) · at 03:04:38Z · abandoned wrun_01M0VE0HVJRVGZC5NAGY22430N
• run-pickup-stall · cancelRun - cancelling a running workflow (python) · at 03:04:38Z · abandoned wrun_01M0VE0HVDHGJS57WFKR4Y7XDS
• run-pickup-stall · sleepInLoopWorkflow - sleep inside loop with steps actually delays each iteration (python) · at 03:05:08Z · abandoned wrun_01M0VE1F35J38MPSCFZMN6YX2P
• run-pickup-stall · WorkflowNotRegisteredError fails the run when workflow does not exist (nextjs-webpack) · at 03:05:16Z · abandoned wrun_01M0VE1QKFX8AWRVN1GKHDE0K9

E2E Test Summary

Summary

	Passed	Failed	Skipped	Total
❌ ▲ Vercel Production	3570	8	742	4320
✅ 💻 Local Development	3922	0	558	4480
✅ 📦 Local Production	3922	0	558	4480
✅ 🐘 Local Postgres	3922	0	558	4480
✅ 🪟 Windows	320	0	0	320
❌ 🌐 Cross-language Conformance	0	9	132	141
✅ vercel-http-transport	817	0	143	960
✅ vercel-multi-region	27	0	0	27
✅ vercel-ws-transport	553	0	87	640
Total	17053	17	2778	19848

Details by Category

❌ ▲ Vercel Production

App	Passed	Failed	Skipped
✅ astro-node	132	0	28
✅ astro-quickjs	132	0	28
✅ example-node	132	0	28
✅ example-quickjs	132	0	28
✅ express-node	132	0	28
✅ express-quickjs	132	0	28
✅ fastify-node	132	0	28
✅ fastify-quickjs	132	0	28
✅ hono-node	132	0	28
✅ hono-quickjs	132	0	28
✅ nest-node	132	0	28
✅ nest-quickjs	132	0	28
✅ nextjs-turbopack-node	157	0	3
✅ nextjs-turbopack-quickjs	157	0	3
✅ nextjs-webpack-node	157	0	3
✅ nextjs-webpack-quickjs	157	0	3
✅ nitro-node	132	0	28
✅ nitro-quickjs	132	0	28
✅ nuxt-node	132	0	28
✅ nuxt-quickjs	132	0	28
❌ python-node	0	8	152
✅ sveltekit-node	151	0	9
✅ sveltekit-quickjs	151	0	9
✅ tanstack-start-node	132	0	28
✅ tanstack-start-quickjs	132	0	28
✅ vite-node	132	0	28
✅ vite-quickjs	132	0	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	141	0	19
✅ nextjs-webpack-canary-quickjs	141	0	19
✅ nextjs-webpack-stable-node	160	0	0
✅ nextjs-webpack-stable-quickjs	160	0	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	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	141	0	19
✅ nextjs-webpack-canary-quickjs	141	0	19
✅ nextjs-webpack-stable-node	160	0	0
✅ nextjs-webpack-stable-quickjs	160	0	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 Postgres

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	141	0	19
✅ nextjs-webpack-canary-quickjs	141	0	19
✅ nextjs-webpack-stable-node	160	0	0
✅ nextjs-webpack-stable-quickjs	160	0	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

✅ 🪟 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	0	9	132

✅ vercel-http-transport

App	Passed	Failed	Skipped
✅ example	132	0	28
✅ express	132	0	28
✅ hono	132	0	28
✅ nextjs-turbopack	157	0	3
✅ nitro	132	0	28
✅ vite	132	0	28

✅ vercel-multi-region

App	Passed	Failed	Skipped
✅ nextjs-turbopack	27	0	0

✅ vercel-ws-transport

App	Passed	Failed	Skipped
✅ example	132	0	28
✅ express	132	0	28
✅ nextjs-turbopack	157	0	3
✅ vite	132	0	28

---

📋 View full workflow run

[github-actions]

📊 Workflow Benchmarks

commit 4834383 · Tue, 25 Aug 2026 03:22:33 GMT · run logs

Backend: vercel · app: nextjs-turbopack

Metric	Scenario	Best (ms)	P75 (ms)	P90 (ms)	P99 (ms)	Samples
TTFS	step	240 (-38%) 💚	1525 🔴 (+39%) 🔻	1574 🔴 (+39%) 🔻	1838 🔴 (+32%) 🔻	30
TTFS	stream	485 (+177%) 🔻	1484 🔴 (+34%) 🔻	1516 🔴 (+34%) 🔻	1567 🔴 (+36%) 🔻	30
TTFS	hook + stream	1712 (+199%) 🔻	1839 🔴 (+35%) 🔻	1897 🔴 (+20%) 🔻	1990 🔴 (-57%) 💚	30
Fan-out TTFS	Promise.all(100 steps)	640 (+2.2%)	2135 (+95%) 🔻	2156 (+39%) 🔻	2292 (-54%) 💚	10
Fan-out TTLS	Promise.all(100 steps)	2612 (+44%) 🔻	4012 (±0%)	4044 (-0.7%)	10348 (+3.9%)	10
STSO	1020 steps (inline)	100 (-11%)	156 (+9.1%)	175 (+5.4%)	281 (+17%) 🔻	1019
WO	1020 steps	157552 (+8.3%)	157552 (+8.3%)	157552 (+8.3%)	157552 (+8.3%)	1
CRTT	first chunk (pooled)	125 (+51%) 🔻	198 (+41%) 🔻	246 (-5.4%)	458 (-35%) 💚	28

Streams

Scenario	CRTT 1st	p75	p90	p99	CDV max	iters
paced control (100/s, 60B)	154 (+38%)	192 (+27%)	257 (-30%)	390 (-42%)	162 (+33%)	10
size sweep (100/s, 160B-12KB)	147 (+31%)	197 (+55%)	323 (+99%)	1023 (+56%)	228 (+111%)	10
replay gateway-gpt-5.4-nano-2000t (1x)	182 (+2%)	146 (-77%)	176 (-92%)	303 (-92%)	211 (-46%)	3
replay eve-gpt-5.6-sol-2000t (1x)	206 (+49%)	163 (+16%)	216 (+14%)	379 (-26%)	221 (-56%)	2
replay eve-gpt-5.6-sol-2000t (2x)	167 (+18%)	208 (+11%)	286 (+6%)	673 (-19%)	290 (+60%)	3

📈 STSO distribution vs main (inline / queue-hop histograms)

1020 steps (inline)

Cumulative STSO time: main 144386ms → this run 156134ms (Δ +11748ms, +8%)

100-150 ms █████████████████┃██████ main 853 this 646 -207
150-200 ms ████░░░░┃ main 138 this 336 +198
200-250 ms ┃ main 19 this 22 +3
250-300 ms ┃ main 4 this 7 +3
300-350 ms ┃ main 5 this 3 -2
350-400 ms ┃ main 0 this 2 +2
400-450 ms ┃ main 0 this 2 +2
600-650 ms ┃ main 0 this 1 +1

📈 CRTT drill-down vs main (RTT distributions & profiles)

variant RTT 1ms→5s+ avg p50 p90 p99 n
control ······▂█▂···· 150.5 (+19%) 135 (+27%) 257 (-30%) 390 (-42%) 3000
sweep ······▂█▂▁▁·· 172.3 (+46%) 145 (+46%) 323 (+99%) 1023 (+56%) 3000
gw 1x ······▃█▁···· 129 (-56%) 125 (+2%) 176 (-92%) 303 (-92%) 5295
eve 1x ······▃█▂···· 138.3 (+14%) 125 (+23%) 216 (+14%) 379 (-26%) 5186
eve 2x ······▁█▃▁··· 171.6 (+16%) 156 (+16%) 286 (+6%) 673 (-19%) 7779

RTT over stream progress (avg per tenth of stream, bars scaled min→max):

control █▇▄▃▂▃▃▁▁▁ 130–189ms
sweep ▃██▅▃▂▁▂▁▂ 133–242ms
gw 1x ▅▄▄█▄▃▂▂▃▁ 120–144ms
eve 1x ▆▂▁▃▁▁██▂▃ 124–166ms
eve 2x ▄▁▃▂▂▆▃▅▆█ 145–207ms

RTT by chunk size (avg per log size bin, ~160B → ~12KB serialized, bars scaled min→max):

sweep █▄▄▄▃▁▄ 170–175ms

Delivery jitter over stream progress (avg positive CDV per tenth of stream, bars scaled min→max):

control ▁▅▃█▄█▄▂▂▁ 40–50ms
sweep ▁▆▅▄▃▆▄▆▃█ 48–65ms
gw 1x ▄▆▃▁▅▂▅█▁▃ 38–43ms
eve 1x ▇▄▁▄▃▃▆▃▂█ 23–32ms
eve 2x █▇▁▂▆▅▄▁▃▆ 24–33ms

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.}

_{The collapsed STSO distribution section above buckets every step gap, split inline (same warm process — pure framework overhead) vs queue-hop (fresh process — dispatch, reinit, replay). █ = main, ┃ = this run, ░ = fill.}

_{The collapsed CRTT drill-down: per-variant RTT histograms (fixed log bins, · = empty) and mean RTT/positive-CDV profile lines over stream progress and chunk size. Histograms, avgs, and profiles merge exactly across runs; p50–p99 are percentile-of-percentiles. Per-index rows live in the artifacts.}

_{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-2000teaf22f5946e7c61f3c65c7006d550df180cfabd4e706254a09f22aec0cfb420d · gateway-gpt-5.4-nano-2000t6f24ac518b6b83ff1d0e85a5fe78230db192716d66a7fc6b2fe022752001d041}

_{🔴 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.}

[VaguelySerious]

AI review: no blocking issues

[TooTallNate]

AI: Approved. I found no blocking issues in the schema-free module split, validation changes, package exports, or bundle-boundary coverage.

[github-actions]

No backport to stable for d62b444 (AI decision).

This is primarily a bundle-size/startup-performance refactor that moves World validation and event-metadata helpers onto new @workflow/world subpath exports and intentionally removes public root-level exports (validateAttributeKey, validateAttributeValue, EVENT_DATA_PAYLOAD_FIELD_BY_EVENT_TYPE, EVENT_DATA_REF_FIELDS) as a deliberate v5 breaking change, carrying a major changeset — exactly the kind of API-surface churn a maintenance line should not take. The two genuine hardening bits (an unknown attribute deletion no longer offsetting a newly added key in the per-run cap accounting in validateAttributeChanges, and prototype-like event type strings such as constructor returning no metadata) are small and could be split out and force-backported on their own if desired. Per the mixed-commit rule, the presence of a breaking refactor makes the whole commit ineligible.

To override, re-run the Backport to stable workflow manually via workflow_dispatch and paste this commit SHA into the ref input:

d62b44473b43e183e71386fe84b33f5e7bb5445c

[NathanColosimo]

Summary

• move runtime-only event metadata and attribute validation onto schema-free @workflow/world subpaths
• keep the public Zod schemas available to hosts without pulling them into the sandbox
• intentionally remove the superseded root-level World validation and event lookup exports as a v5 breaking change
• add regression coverage for both a minimal workflow and normal attribute, hook, and step APIs

Result

For the 97-step benchmark workflow:

• VM bundle: 612,980 B → 26,831 B (-95.6%)
• fresh-context evaluation p50: 10.536 ms → 0.121 ms (-98.9%)
• Zod modules in the benchmark VM bundle: 77 → 0 (workflows that import Zod themselves still include it)

Review scope

Serialized formats are unchanged. Besides the dependency-boundary refactor, this tightens two edge cases: an unknown attribute deletion can no longer offset a newly added key, and prototype-like event type strings safely return no metadata. The @workflow/world changeset is marked major for the intentionally removed public exports; on the current prerelease branch this still produces the next v5 beta.

Validation

• full workspace typecheck
• builders, core, world, and world-vercel package builds/typechecks
• 3,233 package tests across builders, core, world, and world-vercel
• focused workflow-bundle boundary regression tests
• Next/Turbopack and Vite production builds
• clean Codex + Claude autoreview after addressing feedback

[changeset-bot]

🦋 Changeset detected

Latest commit: 4834383

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

This PR includes changesets to release 20 packages

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

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

Project	Deployment	Actions	Updated (UTC)
example-nextjs-workflow-turbopack	Ready	Preview, v0	Aug 25, 2026 2:59am
example-nextjs-workflow-webpack	Ready	Preview, v0	Aug 25, 2026 2:59am
example-workflow	Ready	Preview, v0	Aug 25, 2026 2:59am
workbench-astro-workflow	Ready	Preview, v0	Aug 25, 2026 2:59am
workbench-express-workflow	Ready	Preview, v0	Aug 25, 2026 2:59am
workbench-fastify-workflow	Ready	Preview, v0	Aug 25, 2026 2:59am
workbench-hono-workflow	Ready	Preview, v0	Aug 25, 2026 2:59am
workbench-nestjs-workflow	Ready	Preview, v0	Aug 25, 2026 2:59am
workbench-nitro-workflow	Ready	Preview, v0	Aug 25, 2026 2:59am
workbench-nuxt-workflow	Ready	Preview, v0	Aug 25, 2026 2:59am
workbench-python-workflow	Ready	Preview, v0	Aug 25, 2026 2:59am
workbench-sveltekit-workflow	Ready	Preview, v0	Aug 25, 2026 2:59am
workbench-tanstack-start-workflow	Ready	Preview, v0	Aug 25, 2026 2:59am
workbench-vite-workflow	Ready	Preview, v0	Aug 25, 2026 2:59am
workflow-docs	Ready	Preview, v0	Aug 25, 2026 2:59am
workflow-swc-playground	Ready	Preview, v0	Aug 25, 2026 2:59am
workflow-tarballs	Ready	Preview, v0	Aug 25, 2026 2:59am
workflow-web	Ready	Preview, v0	Aug 25, 2026 2:59am

[github-actions]

🧪 E2E Test Results

❌ Some tests failed

❌ Failed E2E Tests

▲ Vercel Production (8 failed)

python-node (8 failed):

• promiseAllWorkflow | wrun_41M0VDN06C0GJF9R48YSG9WQ30 | 🔍 observability
• sleepingWorkflow | wrun_41M0VDNNN70GXQ8MQGB8DFFBVP | 🔍 observability
• parallelSleepWorkflow | wrun_41M0VDNQ4R0GTSQZ0NV78PS68F | 🔍 observability
• nullByteWorkflow | wrun_41M0VDNXQD0GN74C8N2SH970J4 | 🔍 observability
• cancelRun - cancelling a running workflow | wrun_41M0VDTG7Y0GKNVYEMFAZHAT66 | 🔍 observability
• cancelRun via CLI - cancelling a running workflow | wrun_41M0VDTH470GR3A7GYZW28QRRT | 🔍 observability
• sleepInLoopWorkflow - sleep inside loop with steps actually delays each iteration | wrun_41M0VDTWJP0GGDVNP9TXTDB25Y | 🔍 observability
• resilient start: addTenWorkflow completes when run_created returns 500 | wrun_41M0VDVECE0GW8TM4DBWV2H88X | 🔍 observability

🌐 Cross-language Conformance (9 failed)

python (9 failed):

• deploymentId: 'latest' is a no-op in non-Vercel worlds | wrun_01M0VDY8HAYKF5H611G7HRPJGV
• promiseAllWorkflow | wrun_41M0VDN06C0GJF9R48YSG9WQ30
• sleepingWorkflow | wrun_41M0VDNNN70GXQ8MQGB8DFFBVP
• parallelSleepWorkflow | wrun_41M0VDNQ4R0GTSQZ0NV78PS68F
• nullByteWorkflow | wrun_41M0VDNXQD0GN74C8N2SH970J4
• cancelRun - cancelling a running workflow | wrun_41M0VDTG7Y0GKNVYEMFAZHAT66
• cancelRun via CLI - cancelling a running workflow | wrun_41M0VDTH470GR3A7GYZW28QRRT
• sleepInLoopWorkflow - sleep inside loop with steps actually delays each iteration | wrun_41M0VDTWJP0GGDVNP9TXTDB25Y
• resilient start: addTenWorkflow completes when run_created returns 500 | wrun_41M0VDVECE0GW8TM4DBWV2H88X

⚠️ 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.

• cancelRun via CLI - cancelling a running workflow (nextjs-turbopack)
• hookGetConflictWorkflow - hook.getConflict() resolves with the conflicting run when token is already registered (express)

🛠 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.

34 infra events

• cold-start-warmup · suite warmup (python) · at 02:59:19Z · abandoned wrun_41M0VDKMMW0GH51Y8JG5NNFA53 · (+7 more)
• run-pickup-stall · sleepingWorkflow (python) · at 02:59:35Z · abandoned wrun_41M0VDQ9BQ0GQK2NWX2GHQEVNE
• run-pickup-stall · parallelSleepWorkflow (python) · at 02:59:35Z · abandoned wrun_41M0VDQ9BR0GJ9VX6F75YE9E9Q
• run-pickup-stall · nullByteWorkflow (python) · at 02:59:36Z · abandoned wrun_41M0VDQ9BV0GYFB5RFCSNMCKA8
• run-pickup-stall · promiseAllWorkflow (python) · at 02:59:36Z · abandoned wrun_41M0VDQ9BH0GK9EQXW0CP2ZJCA
• run-pickup-stall · cancelRun - cancelling a running workflow (python) · at 02:59:36Z · abandoned wrun_41M0VDQ9WK0GMVHTNXHTJD781E
• run-pickup-stall · cancelRun - cancelling a running workflow (python) · at 03:00:09Z · abandoned wrun_41M0VDR9R80GNBR3X3RRSVHN07
• run-pickup-stall · nullByteWorkflow (python) · at 03:00:36Z · abandoned wrun_41M0VDS4QY0GH9G06DD4CNPHN0
• run-pickup-stall · promiseAllWorkflow (python) · at 03:00:36Z · abandoned wrun_41M0VDS50Q0GX4S6T0PQTXW632
• run-pickup-stall · sleepingWorkflow (python) · at 03:00:36Z · abandoned wrun_41M0VDS50T0GSG4ZEE82KCJB3M
• run-pickup-stall · parallelSleepWorkflow (python) · at 03:00:36Z · abandoned wrun_41M0VDS4WM0GM7PK0RSWPBVGA0
• cold-start-warmup · suite warmup (tanstack-start) · at 03:00:41Z · abandoned wrun_01M0VDS3CBPAJR0ZH8W972WZZJ
• run-pickup-stall · cancelRun via CLI - cancelling a running workflow (python) · at 03:01:27Z · abandoned wrun_41M0VDS9XE0GTMQHS9QWWG5A2J
• cold-start-warmup · suite warmup (python) · at 03:01:53Z · abandoned wrun_01M0VDRA3CVH1MKDJEYP3V2BDW · (+7 more)
• run-pickup-stall · deploymentId: 'latest' is a no-op in non-Vercel worlds (python) · at 03:02:08Z · abandoned wrun_01M0VDVZ8CVJ5HP9G5FB1A1M3F
• run-pickup-stall · sleepingWorkflow (python) · at 03:02:08Z · abandoned wrun_01M0VDVZ8H5BFT2BTQGSX5M1FZ
• run-pickup-stall · parallelSleepWorkflow (python) · at 03:02:08Z · abandoned wrun_01M0VDVZ8M8XKZTWA23C6T2N7A
• run-pickup-stall · nullByteWorkflow (python) · at 03:02:08Z · abandoned wrun_01M0VDVZ8NTRCFXWR32772DDWJ
• run-pickup-stall · promiseAllWorkflow (python) · at 03:02:08Z · abandoned wrun_01M0VDVZ8DP1T84GQYSC3FST3V
• run-pickup-stall · workflow throws after awaited setAttributes: attribute still persists on the failed run (nuxt) · at 03:03:00Z · abandoned wrun_01M0VDXJ26475QRTXK3E4NYG5E
• run-pickup-stall · deploymentId: 'latest' is a no-op in non-Vercel worlds (python) · at 03:03:08Z · abandoned wrun_01M0VDXSW1STJBAFKY2ZTCJK9G
• run-pickup-stall · sleepingWorkflow (python) · at 03:03:08Z · abandoned wrun_01M0VDXSW5NENDADCH34B3A56A
• run-pickup-stall · promiseAllWorkflow (python) · at 03:03:08Z · abandoned wrun_01M0VDXSW3FS334GPAR9QK29DK
• run-pickup-stall · nullByteWorkflow (python) · at 03:03:08Z · abandoned wrun_01M0VDXSWE2XMMPSNBC595YAX9
• run-pickup-stall · parallelSleepWorkflow (python) · at 03:03:08Z · abandoned wrun_01M0VDXSW8ATGQPPHSTAPYGT45
• run-pickup-stall · cancelRun via CLI - cancelling a running workflow (python) · at 03:03:08Z · abandoned wrun_41M0VDW1SZ0GY2PX4NR4R4Y8X5
• run-pickup-stall · sleepInLoopWorkflow - sleep inside loop with steps actually delays each iteration (python) · at 03:03:08Z · abandoned wrun_41M0VDVWMG0GJ7M15MXRX9SJEM
• run-pickup-stall · cancelRun - cancelling a running workflow (python) · at 03:04:08Z · abandoned wrun_01M0VDZMFMRD0Y1PD7NBT2M72C
• run-pickup-stall · cancelRun via CLI - cancelling a running workflow (python) · at 03:04:08Z · abandoned wrun_01M0VDZMFVFN8Q4FA149CMQ9EQ
• run-pickup-stall · sleepInLoopWorkflow - sleep inside loop with steps actually delays each iteration (python) · at 03:04:08Z · abandoned wrun_01M0VDZMFZ1SM0TW62J5SAFBK3
• run-pickup-stall · cancelRun via CLI - cancelling a running workflow (python) · at 03:04:38Z · abandoned wrun_01M0VE0HVJRVGZC5NAGY22430N
• run-pickup-stall · cancelRun - cancelling a running workflow (python) · at 03:04:38Z · abandoned wrun_01M0VE0HVDHGJS57WFKR4Y7XDS
• run-pickup-stall · sleepInLoopWorkflow - sleep inside loop with steps actually delays each iteration (python) · at 03:05:08Z · abandoned wrun_01M0VE1F35J38MPSCFZMN6YX2P
• run-pickup-stall · WorkflowNotRegisteredError fails the run when workflow does not exist (nextjs-webpack) · at 03:05:16Z · abandoned wrun_01M0VE1QKFX8AWRVN1GKHDE0K9

E2E Test Summary

Summary

	Passed	Failed	Skipped	Total
❌ ▲ Vercel Production	3570	8	742	4320
✅ 💻 Local Development	3922	0	558	4480
✅ 📦 Local Production	3922	0	558	4480
✅ 🐘 Local Postgres	3922	0	558	4480
✅ 🪟 Windows	320	0	0	320
❌ 🌐 Cross-language Conformance	0	9	132	141
✅ vercel-http-transport	817	0	143	960
✅ vercel-multi-region	27	0	0	27
✅ vercel-ws-transport	553	0	87	640
Total	17053	17	2778	19848

Details by Category

❌ ▲ Vercel Production

App	Passed	Failed	Skipped
✅ astro-node	132	0	28
✅ astro-quickjs	132	0	28
✅ example-node	132	0	28
✅ example-quickjs	132	0	28
✅ express-node	132	0	28
✅ express-quickjs	132	0	28
✅ fastify-node	132	0	28
✅ fastify-quickjs	132	0	28
✅ hono-node	132	0	28
✅ hono-quickjs	132	0	28
✅ nest-node	132	0	28
✅ nest-quickjs	132	0	28
✅ nextjs-turbopack-node	157	0	3
✅ nextjs-turbopack-quickjs	157	0	3
✅ nextjs-webpack-node	157	0	3
✅ nextjs-webpack-quickjs	157	0	3
✅ nitro-node	132	0	28
✅ nitro-quickjs	132	0	28
✅ nuxt-node	132	0	28
✅ nuxt-quickjs	132	0	28
❌ python-node	0	8	152
✅ sveltekit-node	151	0	9
✅ sveltekit-quickjs	151	0	9
✅ tanstack-start-node	132	0	28
✅ tanstack-start-quickjs	132	0	28
✅ vite-node	132	0	28
✅ vite-quickjs	132	0	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	141	0	19
✅ nextjs-webpack-canary-quickjs	141	0	19
✅ nextjs-webpack-stable-node	160	0	0
✅ nextjs-webpack-stable-quickjs	160	0	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	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	141	0	19
✅ nextjs-webpack-canary-quickjs	141	0	19
✅ nextjs-webpack-stable-node	160	0	0
✅ nextjs-webpack-stable-quickjs	160	0	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 Postgres

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	141	0	19
✅ nextjs-webpack-canary-quickjs	141	0	19
✅ nextjs-webpack-stable-node	160	0	0
✅ nextjs-webpack-stable-quickjs	160	0	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

✅ 🪟 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	0	9	132

✅ vercel-http-transport

App	Passed	Failed	Skipped
✅ example	132	0	28
✅ express	132	0	28
✅ hono	132	0	28
✅ nextjs-turbopack	157	0	3
✅ nitro	132	0	28
✅ vite	132	0	28

✅ vercel-multi-region

App	Passed	Failed	Skipped
✅ nextjs-turbopack	27	0	0

✅ vercel-ws-transport

App	Passed	Failed	Skipped
✅ example	132	0	28
✅ express	132	0	28
✅ nextjs-turbopack	157	0	3
✅ vite	132	0	28

---

📋 View full workflow run

[github-actions]

📊 Workflow Benchmarks

commit 4834383 · Tue, 25 Aug 2026 03:22:33 GMT · run logs

Backend: vercel · app: nextjs-turbopack

Metric	Scenario	Best (ms)	P75 (ms)	P90 (ms)	P99 (ms)	Samples
TTFS	step	240 (-38%) 💚	1525 🔴 (+39%) 🔻	1574 🔴 (+39%) 🔻	1838 🔴 (+32%) 🔻	30
TTFS	stream	485 (+177%) 🔻	1484 🔴 (+34%) 🔻	1516 🔴 (+34%) 🔻	1567 🔴 (+36%) 🔻	30
TTFS	hook + stream	1712 (+199%) 🔻	1839 🔴 (+35%) 🔻	1897 🔴 (+20%) 🔻	1990 🔴 (-57%) 💚	30
Fan-out TTFS	Promise.all(100 steps)	640 (+2.2%)	2135 (+95%) 🔻	2156 (+39%) 🔻	2292 (-54%) 💚	10
Fan-out TTLS	Promise.all(100 steps)	2612 (+44%) 🔻	4012 (±0%)	4044 (-0.7%)	10348 (+3.9%)	10
STSO	1020 steps (inline)	100 (-11%)	156 (+9.1%)	175 (+5.4%)	281 (+17%) 🔻	1019
WO	1020 steps	157552 (+8.3%)	157552 (+8.3%)	157552 (+8.3%)	157552 (+8.3%)	1
CRTT	first chunk (pooled)	125 (+51%) 🔻	198 (+41%) 🔻	246 (-5.4%)	458 (-35%) 💚	28

Streams

Scenario	CRTT 1st	p75	p90	p99	CDV max	iters
paced control (100/s, 60B)	154 (+38%)	192 (+27%)	257 (-30%)	390 (-42%)	162 (+33%)	10
size sweep (100/s, 160B-12KB)	147 (+31%)	197 (+55%)	323 (+99%)	1023 (+56%)	228 (+111%)	10
replay gateway-gpt-5.4-nano-2000t (1x)	182 (+2%)	146 (-77%)	176 (-92%)	303 (-92%)	211 (-46%)	3
replay eve-gpt-5.6-sol-2000t (1x)	206 (+49%)	163 (+16%)	216 (+14%)	379 (-26%)	221 (-56%)	2
replay eve-gpt-5.6-sol-2000t (2x)	167 (+18%)	208 (+11%)	286 (+6%)	673 (-19%)	290 (+60%)	3

📈 STSO distribution vs main (inline / queue-hop histograms)

1020 steps (inline)

Cumulative STSO time: main 144386ms → this run 156134ms (Δ +11748ms, +8%)

100-150 ms █████████████████┃██████ main 853 this 646 -207
150-200 ms ████░░░░┃ main 138 this 336 +198
200-250 ms ┃ main 19 this 22 +3
250-300 ms ┃ main 4 this 7 +3
300-350 ms ┃ main 5 this 3 -2
350-400 ms ┃ main 0 this 2 +2
400-450 ms ┃ main 0 this 2 +2
600-650 ms ┃ main 0 this 1 +1

📈 CRTT drill-down vs main (RTT distributions & profiles)

variant RTT 1ms→5s+ avg p50 p90 p99 n
control ······▂█▂···· 150.5 (+19%) 135 (+27%) 257 (-30%) 390 (-42%) 3000
sweep ······▂█▂▁▁·· 172.3 (+46%) 145 (+46%) 323 (+99%) 1023 (+56%) 3000
gw 1x ······▃█▁···· 129 (-56%) 125 (+2%) 176 (-92%) 303 (-92%) 5295
eve 1x ······▃█▂···· 138.3 (+14%) 125 (+23%) 216 (+14%) 379 (-26%) 5186
eve 2x ······▁█▃▁··· 171.6 (+16%) 156 (+16%) 286 (+6%) 673 (-19%) 7779

RTT over stream progress (avg per tenth of stream, bars scaled min→max):

control █▇▄▃▂▃▃▁▁▁ 130–189ms
sweep ▃██▅▃▂▁▂▁▂ 133–242ms
gw 1x ▅▄▄█▄▃▂▂▃▁ 120–144ms
eve 1x ▆▂▁▃▁▁██▂▃ 124–166ms
eve 2x ▄▁▃▂▂▆▃▅▆█ 145–207ms

RTT by chunk size (avg per log size bin, ~160B → ~12KB serialized, bars scaled min→max):

sweep █▄▄▄▃▁▄ 170–175ms

Delivery jitter over stream progress (avg positive CDV per tenth of stream, bars scaled min→max):

control ▁▅▃█▄█▄▂▂▁ 40–50ms
sweep ▁▆▅▄▃▆▄▆▃█ 48–65ms
gw 1x ▄▆▃▁▅▂▅█▁▃ 38–43ms
eve 1x ▇▄▁▄▃▃▆▃▂█ 23–32ms
eve 2x █▇▁▂▆▅▄▁▃▆ 24–33ms

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.}

_{The collapsed STSO distribution section above buckets every step gap, split inline (same warm process — pure framework overhead) vs queue-hop (fresh process — dispatch, reinit, replay). █ = main, ┃ = this run, ░ = fill.}

_{The collapsed CRTT drill-down: per-variant RTT histograms (fixed log bins, · = empty) and mean RTT/positive-CDV profile lines over stream progress and chunk size. Histograms, avgs, and profiles merge exactly across runs; p50–p99 are percentile-of-percentiles. Per-index rows live in the artifacts.}

_{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-2000teaf22f5946e7c61f3c65c7006d550df180cfabd4e706254a09f22aec0cfb420d · gateway-gpt-5.4-nano-2000t6f24ac518b6b83ff1d0e85a5fe78230db192716d66a7fc6b2fe022752001d041}

_{🔴 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.}

[VaguelySerious]

AI review: no blocking issues

[TooTallNate]

AI: Approved. I found no blocking issues in the schema-free module split, validation changes, package exports, or bundle-boundary coverage.

[github-actions]

No backport to stable for d62b444 (AI decision).

This is primarily a bundle-size/startup-performance refactor that moves World validation and event-metadata helpers onto new @workflow/world subpath exports and intentionally removes public root-level exports (validateAttributeKey, validateAttributeValue, EVENT_DATA_PAYLOAD_FIELD_BY_EVENT_TYPE, EVENT_DATA_REF_FIELDS) as a deliberate v5 breaking change, carrying a major changeset — exactly the kind of API-surface churn a maintenance line should not take. The two genuine hardening bits (an unknown attribute deletion no longer offsetting a newly added key in the per-run cap accounting in validateAttributeChanges, and prototype-like event type strings such as constructor returning no metadata) are small and could be split out and force-backported on their own if desired. Per the mixed-commit rule, the presence of a breaking refactor makes the whole commit ineligible.

To override, re-run the Backport to stable workflow manually via workflow_dispatch and paste this commit SHA into the ref input:

d62b44473b43e183e71386fe84b33f5e7bb5445c

[NathanColosimo]

Summary

• move runtime-only event metadata and attribute validation onto schema-free @workflow/world subpaths
• keep the public Zod schemas available to hosts without pulling them into the sandbox
• intentionally remove the superseded root-level World validation and event lookup exports as a v5 breaking change
• add regression coverage for both a minimal workflow and normal attribute, hook, and step APIs

Result

For the 97-step benchmark workflow:

• VM bundle: 612,980 B → 26,831 B (-95.6%)
• fresh-context evaluation p50: 10.536 ms → 0.121 ms (-98.9%)
• Zod modules in the benchmark VM bundle: 77 → 0 (workflows that import Zod themselves still include it)

Review scope

Serialized formats are unchanged. Besides the dependency-boundary refactor, this tightens two edge cases: an unknown attribute deletion can no longer offset a newly added key, and prototype-like event type strings safely return no metadata. The @workflow/world changeset is marked major for the intentionally removed public exports; on the current prerelease branch this still produces the next v5 beta.

Validation

• full workspace typecheck
• builders, core, world, and world-vercel package builds/typechecks
• 3,233 package tests across builders, core, world, and world-vercel
• focused workflow-bundle boundary regression tests
• Next/Turbopack and Vite production builds
• clean Codex + Claude autoreview after addressing feedback

[changeset-bot]

🦋 Changeset detected

Latest commit: 4834383

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

This PR includes changesets to release 20 packages

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

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

Project	Deployment	Actions	Updated (UTC)
example-nextjs-workflow-turbopack	Ready	Preview, v0	Aug 25, 2026 2:59am
example-nextjs-workflow-webpack	Ready	Preview, v0	Aug 25, 2026 2:59am
example-workflow	Ready	Preview, v0	Aug 25, 2026 2:59am
workbench-astro-workflow	Ready	Preview, v0	Aug 25, 2026 2:59am
workbench-express-workflow	Ready	Preview, v0	Aug 25, 2026 2:59am
workbench-fastify-workflow	Ready	Preview, v0	Aug 25, 2026 2:59am
workbench-hono-workflow	Ready	Preview, v0	Aug 25, 2026 2:59am
workbench-nestjs-workflow	Ready	Preview, v0	Aug 25, 2026 2:59am
workbench-nitro-workflow	Ready	Preview, v0	Aug 25, 2026 2:59am
workbench-nuxt-workflow	Ready	Preview, v0	Aug 25, 2026 2:59am
workbench-python-workflow	Ready	Preview, v0	Aug 25, 2026 2:59am
workbench-sveltekit-workflow	Ready	Preview, v0	Aug 25, 2026 2:59am
workbench-tanstack-start-workflow	Ready	Preview, v0	Aug 25, 2026 2:59am
workbench-vite-workflow	Ready	Preview, v0	Aug 25, 2026 2:59am
workflow-docs	Ready	Preview, v0	Aug 25, 2026 2:59am
workflow-swc-playground	Ready	Preview, v0	Aug 25, 2026 2:59am
workflow-tarballs	Ready	Preview, v0	Aug 25, 2026 2:59am
workflow-web	Ready	Preview, v0	Aug 25, 2026 2:59am

[github-actions]

🧪 E2E Test Results

❌ Some tests failed

❌ Failed E2E Tests

▲ Vercel Production (8 failed)

python-node (8 failed):

• promiseAllWorkflow | wrun_41M0VDN06C0GJF9R48YSG9WQ30 | 🔍 observability
• sleepingWorkflow | wrun_41M0VDNNN70GXQ8MQGB8DFFBVP | 🔍 observability
• parallelSleepWorkflow | wrun_41M0VDNQ4R0GTSQZ0NV78PS68F | 🔍 observability
• nullByteWorkflow | wrun_41M0VDNXQD0GN74C8N2SH970J4 | 🔍 observability
• cancelRun - cancelling a running workflow | wrun_41M0VDTG7Y0GKNVYEMFAZHAT66 | 🔍 observability
• cancelRun via CLI - cancelling a running workflow | wrun_41M0VDTH470GR3A7GYZW28QRRT | 🔍 observability
• sleepInLoopWorkflow - sleep inside loop with steps actually delays each iteration | wrun_41M0VDTWJP0GGDVNP9TXTDB25Y | 🔍 observability
• resilient start: addTenWorkflow completes when run_created returns 500 | wrun_41M0VDVECE0GW8TM4DBWV2H88X | 🔍 observability

🌐 Cross-language Conformance (9 failed)

python (9 failed):

• deploymentId: 'latest' is a no-op in non-Vercel worlds | wrun_01M0VDY8HAYKF5H611G7HRPJGV
• promiseAllWorkflow | wrun_41M0VDN06C0GJF9R48YSG9WQ30
• sleepingWorkflow | wrun_41M0VDNNN70GXQ8MQGB8DFFBVP
• parallelSleepWorkflow | wrun_41M0VDNQ4R0GTSQZ0NV78PS68F
• nullByteWorkflow | wrun_41M0VDNXQD0GN74C8N2SH970J4
• cancelRun - cancelling a running workflow | wrun_41M0VDTG7Y0GKNVYEMFAZHAT66
• cancelRun via CLI - cancelling a running workflow | wrun_41M0VDTH470GR3A7GYZW28QRRT
• sleepInLoopWorkflow - sleep inside loop with steps actually delays each iteration | wrun_41M0VDTWJP0GGDVNP9TXTDB25Y
• resilient start: addTenWorkflow completes when run_created returns 500 | wrun_41M0VDVECE0GW8TM4DBWV2H88X

⚠️ 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.

• cancelRun via CLI - cancelling a running workflow (nextjs-turbopack)
• hookGetConflictWorkflow - hook.getConflict() resolves with the conflicting run when token is already registered (express)

🛠 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.

34 infra events

• cold-start-warmup · suite warmup (python) · at 02:59:19Z · abandoned wrun_41M0VDKMMW0GH51Y8JG5NNFA53 · (+7 more)
• run-pickup-stall · sleepingWorkflow (python) · at 02:59:35Z · abandoned wrun_41M0VDQ9BQ0GQK2NWX2GHQEVNE
• run-pickup-stall · parallelSleepWorkflow (python) · at 02:59:35Z · abandoned wrun_41M0VDQ9BR0GJ9VX6F75YE9E9Q
• run-pickup-stall · nullByteWorkflow (python) · at 02:59:36Z · abandoned wrun_41M0VDQ9BV0GYFB5RFCSNMCKA8
• run-pickup-stall · promiseAllWorkflow (python) · at 02:59:36Z · abandoned wrun_41M0VDQ9BH0GK9EQXW0CP2ZJCA
• run-pickup-stall · cancelRun - cancelling a running workflow (python) · at 02:59:36Z · abandoned wrun_41M0VDQ9WK0GMVHTNXHTJD781E
• run-pickup-stall · cancelRun - cancelling a running workflow (python) · at 03:00:09Z · abandoned wrun_41M0VDR9R80GNBR3X3RRSVHN07
• run-pickup-stall · nullByteWorkflow (python) · at 03:00:36Z · abandoned wrun_41M0VDS4QY0GH9G06DD4CNPHN0
• run-pickup-stall · promiseAllWorkflow (python) · at 03:00:36Z · abandoned wrun_41M0VDS50Q0GX4S6T0PQTXW632
• run-pickup-stall · sleepingWorkflow (python) · at 03:00:36Z · abandoned wrun_41M0VDS50T0GSG4ZEE82KCJB3M
• run-pickup-stall · parallelSleepWorkflow (python) · at 03:00:36Z · abandoned wrun_41M0VDS4WM0GM7PK0RSWPBVGA0
• cold-start-warmup · suite warmup (tanstack-start) · at 03:00:41Z · abandoned wrun_01M0VDS3CBPAJR0ZH8W972WZZJ
• run-pickup-stall · cancelRun via CLI - cancelling a running workflow (python) · at 03:01:27Z · abandoned wrun_41M0VDS9XE0GTMQHS9QWWG5A2J
• cold-start-warmup · suite warmup (python) · at 03:01:53Z · abandoned wrun_01M0VDRA3CVH1MKDJEYP3V2BDW · (+7 more)
• run-pickup-stall · deploymentId: 'latest' is a no-op in non-Vercel worlds (python) · at 03:02:08Z · abandoned wrun_01M0VDVZ8CVJ5HP9G5FB1A1M3F
• run-pickup-stall · sleepingWorkflow (python) · at 03:02:08Z · abandoned wrun_01M0VDVZ8H5BFT2BTQGSX5M1FZ
• run-pickup-stall · parallelSleepWorkflow (python) · at 03:02:08Z · abandoned wrun_01M0VDVZ8M8XKZTWA23C6T2N7A
• run-pickup-stall · nullByteWorkflow (python) · at 03:02:08Z · abandoned wrun_01M0VDVZ8NTRCFXWR32772DDWJ
• run-pickup-stall · promiseAllWorkflow (python) · at 03:02:08Z · abandoned wrun_01M0VDVZ8DP1T84GQYSC3FST3V
• run-pickup-stall · workflow throws after awaited setAttributes: attribute still persists on the failed run (nuxt) · at 03:03:00Z · abandoned wrun_01M0VDXJ26475QRTXK3E4NYG5E
• run-pickup-stall · deploymentId: 'latest' is a no-op in non-Vercel worlds (python) · at 03:03:08Z · abandoned wrun_01M0VDXSW1STJBAFKY2ZTCJK9G
• run-pickup-stall · sleepingWorkflow (python) · at 03:03:08Z · abandoned wrun_01M0VDXSW5NENDADCH34B3A56A
• run-pickup-stall · promiseAllWorkflow (python) · at 03:03:08Z · abandoned wrun_01M0VDXSW3FS334GPAR9QK29DK
• run-pickup-stall · nullByteWorkflow (python) · at 03:03:08Z · abandoned wrun_01M0VDXSWE2XMMPSNBC595YAX9
• run-pickup-stall · parallelSleepWorkflow (python) · at 03:03:08Z · abandoned wrun_01M0VDXSW8ATGQPPHSTAPYGT45
• run-pickup-stall · cancelRun via CLI - cancelling a running workflow (python) · at 03:03:08Z · abandoned wrun_41M0VDW1SZ0GY2PX4NR4R4Y8X5
• run-pickup-stall · sleepInLoopWorkflow - sleep inside loop with steps actually delays each iteration (python) · at 03:03:08Z · abandoned wrun_41M0VDVWMG0GJ7M15MXRX9SJEM
• run-pickup-stall · cancelRun - cancelling a running workflow (python) · at 03:04:08Z · abandoned wrun_01M0VDZMFMRD0Y1PD7NBT2M72C
• run-pickup-stall · cancelRun via CLI - cancelling a running workflow (python) · at 03:04:08Z · abandoned wrun_01M0VDZMFVFN8Q4FA149CMQ9EQ
• run-pickup-stall · sleepInLoopWorkflow - sleep inside loop with steps actually delays each iteration (python) · at 03:04:08Z · abandoned wrun_01M0VDZMFZ1SM0TW62J5SAFBK3
• run-pickup-stall · cancelRun via CLI - cancelling a running workflow (python) · at 03:04:38Z · abandoned wrun_01M0VE0HVJRVGZC5NAGY22430N
• run-pickup-stall · cancelRun - cancelling a running workflow (python) · at 03:04:38Z · abandoned wrun_01M0VE0HVDHGJS57WFKR4Y7XDS
• run-pickup-stall · sleepInLoopWorkflow - sleep inside loop with steps actually delays each iteration (python) · at 03:05:08Z · abandoned wrun_01M0VE1F35J38MPSCFZMN6YX2P
• run-pickup-stall · WorkflowNotRegisteredError fails the run when workflow does not exist (nextjs-webpack) · at 03:05:16Z · abandoned wrun_01M0VE1QKFX8AWRVN1GKHDE0K9

E2E Test Summary

Summary

	Passed	Failed	Skipped	Total
❌ ▲ Vercel Production	3570	8	742	4320
✅ 💻 Local Development	3922	0	558	4480
✅ 📦 Local Production	3922	0	558	4480
✅ 🐘 Local Postgres	3922	0	558	4480
✅ 🪟 Windows	320	0	0	320
❌ 🌐 Cross-language Conformance	0	9	132	141
✅ vercel-http-transport	817	0	143	960
✅ vercel-multi-region	27	0	0	27
✅ vercel-ws-transport	553	0	87	640
Total	17053	17	2778	19848

Details by Category

❌ ▲ Vercel Production

App	Passed	Failed	Skipped
✅ astro-node	132	0	28
✅ astro-quickjs	132	0	28
✅ example-node	132	0	28
✅ example-quickjs	132	0	28
✅ express-node	132	0	28
✅ express-quickjs	132	0	28
✅ fastify-node	132	0	28
✅ fastify-quickjs	132	0	28
✅ hono-node	132	0	28
✅ hono-quickjs	132	0	28
✅ nest-node	132	0	28
✅ nest-quickjs	132	0	28
✅ nextjs-turbopack-node	157	0	3
✅ nextjs-turbopack-quickjs	157	0	3
✅ nextjs-webpack-node	157	0	3
✅ nextjs-webpack-quickjs	157	0	3
✅ nitro-node	132	0	28
✅ nitro-quickjs	132	0	28
✅ nuxt-node	132	0	28
✅ nuxt-quickjs	132	0	28
❌ python-node	0	8	152
✅ sveltekit-node	151	0	9
✅ sveltekit-quickjs	151	0	9
✅ tanstack-start-node	132	0	28
✅ tanstack-start-quickjs	132	0	28
✅ vite-node	132	0	28
✅ vite-quickjs	132	0	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	141	0	19
✅ nextjs-webpack-canary-quickjs	141	0	19
✅ nextjs-webpack-stable-node	160	0	0
✅ nextjs-webpack-stable-quickjs	160	0	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	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	141	0	19
✅ nextjs-webpack-canary-quickjs	141	0	19
✅ nextjs-webpack-stable-node	160	0	0
✅ nextjs-webpack-stable-quickjs	160	0	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 Postgres

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	141	0	19
✅ nextjs-webpack-canary-quickjs	141	0	19
✅ nextjs-webpack-stable-node	160	0	0
✅ nextjs-webpack-stable-quickjs	160	0	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

✅ 🪟 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	0	9	132

✅ vercel-http-transport

App	Passed	Failed	Skipped
✅ example	132	0	28
✅ express	132	0	28
✅ hono	132	0	28
✅ nextjs-turbopack	157	0	3
✅ nitro	132	0	28
✅ vite	132	0	28

✅ vercel-multi-region

App	Passed	Failed	Skipped
✅ nextjs-turbopack	27	0	0

✅ vercel-ws-transport

App	Passed	Failed	Skipped
✅ example	132	0	28
✅ express	132	0	28
✅ nextjs-turbopack	157	0	3
✅ vite	132	0	28

---

📋 View full workflow run

[github-actions]

📊 Workflow Benchmarks

commit 4834383 · Tue, 25 Aug 2026 03:22:33 GMT · run logs

Backend: vercel · app: nextjs-turbopack

Metric	Scenario	Best (ms)	P75 (ms)	P90 (ms)	P99 (ms)	Samples
TTFS	step	240 (-38%) 💚	1525 🔴 (+39%) 🔻	1574 🔴 (+39%) 🔻	1838 🔴 (+32%) 🔻	30
TTFS	stream	485 (+177%) 🔻	1484 🔴 (+34%) 🔻	1516 🔴 (+34%) 🔻	1567 🔴 (+36%) 🔻	30
TTFS	hook + stream	1712 (+199%) 🔻	1839 🔴 (+35%) 🔻	1897 🔴 (+20%) 🔻	1990 🔴 (-57%) 💚	30
Fan-out TTFS	Promise.all(100 steps)	640 (+2.2%)	2135 (+95%) 🔻	2156 (+39%) 🔻	2292 (-54%) 💚	10
Fan-out TTLS	Promise.all(100 steps)	2612 (+44%) 🔻	4012 (±0%)	4044 (-0.7%)	10348 (+3.9%)	10
STSO	1020 steps (inline)	100 (-11%)	156 (+9.1%)	175 (+5.4%)	281 (+17%) 🔻	1019
WO	1020 steps	157552 (+8.3%)	157552 (+8.3%)	157552 (+8.3%)	157552 (+8.3%)	1
CRTT	first chunk (pooled)	125 (+51%) 🔻	198 (+41%) 🔻	246 (-5.4%)	458 (-35%) 💚	28

Streams

Scenario	CRTT 1st	p75	p90	p99	CDV max	iters
paced control (100/s, 60B)	154 (+38%)	192 (+27%)	257 (-30%)	390 (-42%)	162 (+33%)	10
size sweep (100/s, 160B-12KB)	147 (+31%)	197 (+55%)	323 (+99%)	1023 (+56%)	228 (+111%)	10
replay gateway-gpt-5.4-nano-2000t (1x)	182 (+2%)	146 (-77%)	176 (-92%)	303 (-92%)	211 (-46%)	3
replay eve-gpt-5.6-sol-2000t (1x)	206 (+49%)	163 (+16%)	216 (+14%)	379 (-26%)	221 (-56%)	2
replay eve-gpt-5.6-sol-2000t (2x)	167 (+18%)	208 (+11%)	286 (+6%)	673 (-19%)	290 (+60%)	3

📈 STSO distribution vs main (inline / queue-hop histograms)

1020 steps (inline)

Cumulative STSO time: main 144386ms → this run 156134ms (Δ +11748ms, +8%)

100-150 ms █████████████████┃██████ main 853 this 646 -207
150-200 ms ████░░░░┃ main 138 this 336 +198
200-250 ms ┃ main 19 this 22 +3
250-300 ms ┃ main 4 this 7 +3
300-350 ms ┃ main 5 this 3 -2
350-400 ms ┃ main 0 this 2 +2
400-450 ms ┃ main 0 this 2 +2
600-650 ms ┃ main 0 this 1 +1

📈 CRTT drill-down vs main (RTT distributions & profiles)

variant RTT 1ms→5s+ avg p50 p90 p99 n
control ······▂█▂···· 150.5 (+19%) 135 (+27%) 257 (-30%) 390 (-42%) 3000
sweep ······▂█▂▁▁·· 172.3 (+46%) 145 (+46%) 323 (+99%) 1023 (+56%) 3000
gw 1x ······▃█▁···· 129 (-56%) 125 (+2%) 176 (-92%) 303 (-92%) 5295
eve 1x ······▃█▂···· 138.3 (+14%) 125 (+23%) 216 (+14%) 379 (-26%) 5186
eve 2x ······▁█▃▁··· 171.6 (+16%) 156 (+16%) 286 (+6%) 673 (-19%) 7779

RTT over stream progress (avg per tenth of stream, bars scaled min→max):

control █▇▄▃▂▃▃▁▁▁ 130–189ms
sweep ▃██▅▃▂▁▂▁▂ 133–242ms
gw 1x ▅▄▄█▄▃▂▂▃▁ 120–144ms
eve 1x ▆▂▁▃▁▁██▂▃ 124–166ms
eve 2x ▄▁▃▂▂▆▃▅▆█ 145–207ms

RTT by chunk size (avg per log size bin, ~160B → ~12KB serialized, bars scaled min→max):

sweep █▄▄▄▃▁▄ 170–175ms

Delivery jitter over stream progress (avg positive CDV per tenth of stream, bars scaled min→max):

control ▁▅▃█▄█▄▂▂▁ 40–50ms
sweep ▁▆▅▄▃▆▄▆▃█ 48–65ms
gw 1x ▄▆▃▁▅▂▅█▁▃ 38–43ms
eve 1x ▇▄▁▄▃▃▆▃▂█ 23–32ms
eve 2x █▇▁▂▆▅▄▁▃▆ 24–33ms

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.}

_{The collapsed STSO distribution section above buckets every step gap, split inline (same warm process — pure framework overhead) vs queue-hop (fresh process — dispatch, reinit, replay). █ = main, ┃ = this run, ░ = fill.}

_{The collapsed CRTT drill-down: per-variant RTT histograms (fixed log bins, · = empty) and mean RTT/positive-CDV profile lines over stream progress and chunk size. Histograms, avgs, and profiles merge exactly across runs; p50–p99 are percentile-of-percentiles. Per-index rows live in the artifacts.}

_{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-2000teaf22f5946e7c61f3c65c7006d550df180cfabd4e706254a09f22aec0cfb420d · gateway-gpt-5.4-nano-2000t6f24ac518b6b83ff1d0e85a5fe78230db192716d66a7fc6b2fe022752001d041}

_{🔴 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.}

[VaguelySerious]

AI review: no blocking issues

[TooTallNate]

AI: Approved. I found no blocking issues in the schema-free module split, validation changes, package exports, or bundle-boundary coverage.

[github-actions]

No backport to stable for d62b444 (AI decision).

This is primarily a bundle-size/startup-performance refactor that moves World validation and event-metadata helpers onto new @workflow/world subpath exports and intentionally removes public root-level exports (validateAttributeKey, validateAttributeValue, EVENT_DATA_PAYLOAD_FIELD_BY_EVENT_TYPE, EVENT_DATA_REF_FIELDS) as a deliberate v5 breaking change, carrying a major changeset — exactly the kind of API-surface churn a maintenance line should not take. The two genuine hardening bits (an unknown attribute deletion no longer offsetting a newly added key in the per-run cap accounting in validateAttributeChanges, and prototype-like event type strings such as constructor returning no metadata) are small and could be split out and force-backported on their own if desired. Per the mixed-commit rule, the presence of a breaking refactor makes the whole commit ineligible.

To override, re-run the Backport to stable workflow manually via workflow_dispatch and paste this commit SHA into the ref input:

d62b44473b43e183e71386fe84b33f5e7bb5445c

[NathanColosimo]

Summary

• move runtime-only event metadata and attribute validation onto schema-free @workflow/world subpaths
• keep the public Zod schemas available to hosts without pulling them into the sandbox
• intentionally remove the superseded root-level World validation and event lookup exports as a v5 breaking change
• add regression coverage for both a minimal workflow and normal attribute, hook, and step APIs

Result

For the 97-step benchmark workflow:

• VM bundle: 612,980 B → 26,831 B (-95.6%)
• fresh-context evaluation p50: 10.536 ms → 0.121 ms (-98.9%)
• Zod modules in the benchmark VM bundle: 77 → 0 (workflows that import Zod themselves still include it)

Review scope

Serialized formats are unchanged. Besides the dependency-boundary refactor, this tightens two edge cases: an unknown attribute deletion can no longer offset a newly added key, and prototype-like event type strings safely return no metadata. The @workflow/world changeset is marked major for the intentionally removed public exports; on the current prerelease branch this still produces the next v5 beta.

Validation

• full workspace typecheck
• builders, core, world, and world-vercel package builds/typechecks
• 3,233 package tests across builders, core, world, and world-vercel
• focused workflow-bundle boundary regression tests
• Next/Turbopack and Vite production builds
• clean Codex + Claude autoreview after addressing feedback

[changeset-bot]

🦋 Changeset detected

Latest commit: 4834383

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

This PR includes changesets to release 20 packages

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

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

Project	Deployment	Actions	Updated (UTC)
example-nextjs-workflow-turbopack	Ready	Preview, v0	Aug 25, 2026 2:59am
example-nextjs-workflow-webpack	Ready	Preview, v0	Aug 25, 2026 2:59am
example-workflow	Ready	Preview, v0	Aug 25, 2026 2:59am
workbench-astro-workflow	Ready	Preview, v0	Aug 25, 2026 2:59am
workbench-express-workflow	Ready	Preview, v0	Aug 25, 2026 2:59am
workbench-fastify-workflow	Ready	Preview, v0	Aug 25, 2026 2:59am
workbench-hono-workflow	Ready	Preview, v0	Aug 25, 2026 2:59am
workbench-nestjs-workflow	Ready	Preview, v0	Aug 25, 2026 2:59am
workbench-nitro-workflow	Ready	Preview, v0	Aug 25, 2026 2:59am
workbench-nuxt-workflow	Ready	Preview, v0	Aug 25, 2026 2:59am
workbench-python-workflow	Ready	Preview, v0	Aug 25, 2026 2:59am
workbench-sveltekit-workflow	Ready	Preview, v0	Aug 25, 2026 2:59am
workbench-tanstack-start-workflow	Ready	Preview, v0	Aug 25, 2026 2:59am
workbench-vite-workflow	Ready	Preview, v0	Aug 25, 2026 2:59am
workflow-docs	Ready	Preview, v0	Aug 25, 2026 2:59am
workflow-swc-playground	Ready	Preview, v0	Aug 25, 2026 2:59am
workflow-tarballs	Ready	Preview, v0	Aug 25, 2026 2:59am
workflow-web	Ready	Preview, v0	Aug 25, 2026 2:59am

[github-actions]

🧪 E2E Test Results

❌ Some tests failed

❌ Failed E2E Tests

▲ Vercel Production (8 failed)

python-node (8 failed):

• promiseAllWorkflow | wrun_41M0VDN06C0GJF9R48YSG9WQ30 | 🔍 observability
• sleepingWorkflow | wrun_41M0VDNNN70GXQ8MQGB8DFFBVP | 🔍 observability
• parallelSleepWorkflow | wrun_41M0VDNQ4R0GTSQZ0NV78PS68F | 🔍 observability
• nullByteWorkflow | wrun_41M0VDNXQD0GN74C8N2SH970J4 | 🔍 observability
• cancelRun - cancelling a running workflow | wrun_41M0VDTG7Y0GKNVYEMFAZHAT66 | 🔍 observability
• cancelRun via CLI - cancelling a running workflow | wrun_41M0VDTH470GR3A7GYZW28QRRT | 🔍 observability
• sleepInLoopWorkflow - sleep inside loop with steps actually delays each iteration | wrun_41M0VDTWJP0GGDVNP9TXTDB25Y | 🔍 observability
• resilient start: addTenWorkflow completes when run_created returns 500 | wrun_41M0VDVECE0GW8TM4DBWV2H88X | 🔍 observability

🌐 Cross-language Conformance (9 failed)

python (9 failed):

• deploymentId: 'latest' is a no-op in non-Vercel worlds | wrun_01M0VDY8HAYKF5H611G7HRPJGV
• promiseAllWorkflow | wrun_41M0VDN06C0GJF9R48YSG9WQ30
• sleepingWorkflow | wrun_41M0VDNNN70GXQ8MQGB8DFFBVP
• parallelSleepWorkflow | wrun_41M0VDNQ4R0GTSQZ0NV78PS68F
• nullByteWorkflow | wrun_41M0VDNXQD0GN74C8N2SH970J4
• cancelRun - cancelling a running workflow | wrun_41M0VDTG7Y0GKNVYEMFAZHAT66
• cancelRun via CLI - cancelling a running workflow | wrun_41M0VDTH470GR3A7GYZW28QRRT
• sleepInLoopWorkflow - sleep inside loop with steps actually delays each iteration | wrun_41M0VDTWJP0GGDVNP9TXTDB25Y
• resilient start: addTenWorkflow completes when run_created returns 500 | wrun_41M0VDVECE0GW8TM4DBWV2H88X

⚠️ 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.

• cancelRun via CLI - cancelling a running workflow (nextjs-turbopack)
• hookGetConflictWorkflow - hook.getConflict() resolves with the conflicting run when token is already registered (express)

🛠 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.

34 infra events

• cold-start-warmup · suite warmup (python) · at 02:59:19Z · abandoned wrun_41M0VDKMMW0GH51Y8JG5NNFA53 · (+7 more)
• run-pickup-stall · sleepingWorkflow (python) · at 02:59:35Z · abandoned wrun_41M0VDQ9BQ0GQK2NWX2GHQEVNE
• run-pickup-stall · parallelSleepWorkflow (python) · at 02:59:35Z · abandoned wrun_41M0VDQ9BR0GJ9VX6F75YE9E9Q
• run-pickup-stall · nullByteWorkflow (python) · at 02:59:36Z · abandoned wrun_41M0VDQ9BV0GYFB5RFCSNMCKA8
• run-pickup-stall · promiseAllWorkflow (python) · at 02:59:36Z · abandoned wrun_41M0VDQ9BH0GK9EQXW0CP2ZJCA
• run-pickup-stall · cancelRun - cancelling a running workflow (python) · at 02:59:36Z · abandoned wrun_41M0VDQ9WK0GMVHTNXHTJD781E
• run-pickup-stall · cancelRun - cancelling a running workflow (python) · at 03:00:09Z · abandoned wrun_41M0VDR9R80GNBR3X3RRSVHN07
• run-pickup-stall · nullByteWorkflow (python) · at 03:00:36Z · abandoned wrun_41M0VDS4QY0GH9G06DD4CNPHN0
• run-pickup-stall · promiseAllWorkflow (python) · at 03:00:36Z · abandoned wrun_41M0VDS50Q0GX4S6T0PQTXW632
• run-pickup-stall · sleepingWorkflow (python) · at 03:00:36Z · abandoned wrun_41M0VDS50T0GSG4ZEE82KCJB3M
• run-pickup-stall · parallelSleepWorkflow (python) · at 03:00:36Z · abandoned wrun_41M0VDS4WM0GM7PK0RSWPBVGA0
• cold-start-warmup · suite warmup (tanstack-start) · at 03:00:41Z · abandoned wrun_01M0VDS3CBPAJR0ZH8W972WZZJ
• run-pickup-stall · cancelRun via CLI - cancelling a running workflow (python) · at 03:01:27Z · abandoned wrun_41M0VDS9XE0GTMQHS9QWWG5A2J
• cold-start-warmup · suite warmup (python) · at 03:01:53Z · abandoned wrun_01M0VDRA3CVH1MKDJEYP3V2BDW · (+7 more)
• run-pickup-stall · deploymentId: 'latest' is a no-op in non-Vercel worlds (python) · at 03:02:08Z · abandoned wrun_01M0VDVZ8CVJ5HP9G5FB1A1M3F
• run-pickup-stall · sleepingWorkflow (python) · at 03:02:08Z · abandoned wrun_01M0VDVZ8H5BFT2BTQGSX5M1FZ
• run-pickup-stall · parallelSleepWorkflow (python) · at 03:02:08Z · abandoned wrun_01M0VDVZ8M8XKZTWA23C6T2N7A
• run-pickup-stall · nullByteWorkflow (python) · at 03:02:08Z · abandoned wrun_01M0VDVZ8NTRCFXWR32772DDWJ
• run-pickup-stall · promiseAllWorkflow (python) · at 03:02:08Z · abandoned wrun_01M0VDVZ8DP1T84GQYSC3FST3V
• run-pickup-stall · workflow throws after awaited setAttributes: attribute still persists on the failed run (nuxt) · at 03:03:00Z · abandoned wrun_01M0VDXJ26475QRTXK3E4NYG5E
• run-pickup-stall · deploymentId: 'latest' is a no-op in non-Vercel worlds (python) · at 03:03:08Z · abandoned wrun_01M0VDXSW1STJBAFKY2ZTCJK9G
• run-pickup-stall · sleepingWorkflow (python) · at 03:03:08Z · abandoned wrun_01M0VDXSW5NENDADCH34B3A56A
• run-pickup-stall · promiseAllWorkflow (python) · at 03:03:08Z · abandoned wrun_01M0VDXSW3FS334GPAR9QK29DK
• run-pickup-stall · nullByteWorkflow (python) · at 03:03:08Z · abandoned wrun_01M0VDXSWE2XMMPSNBC595YAX9
• run-pickup-stall · parallelSleepWorkflow (python) · at 03:03:08Z · abandoned wrun_01M0VDXSW8ATGQPPHSTAPYGT45
• run-pickup-stall · cancelRun via CLI - cancelling a running workflow (python) · at 03:03:08Z · abandoned wrun_41M0VDW1SZ0GY2PX4NR4R4Y8X5
• run-pickup-stall · sleepInLoopWorkflow - sleep inside loop with steps actually delays each iteration (python) · at 03:03:08Z · abandoned wrun_41M0VDVWMG0GJ7M15MXRX9SJEM
• run-pickup-stall · cancelRun - cancelling a running workflow (python) · at 03:04:08Z · abandoned wrun_01M0VDZMFMRD0Y1PD7NBT2M72C
• run-pickup-stall · cancelRun via CLI - cancelling a running workflow (python) · at 03:04:08Z · abandoned wrun_01M0VDZMFVFN8Q4FA149CMQ9EQ
• run-pickup-stall · sleepInLoopWorkflow - sleep inside loop with steps actually delays each iteration (python) · at 03:04:08Z · abandoned wrun_01M0VDZMFZ1SM0TW62J5SAFBK3
• run-pickup-stall · cancelRun via CLI - cancelling a running workflow (python) · at 03:04:38Z · abandoned wrun_01M0VE0HVJRVGZC5NAGY22430N
• run-pickup-stall · cancelRun - cancelling a running workflow (python) · at 03:04:38Z · abandoned wrun_01M0VE0HVDHGJS57WFKR4Y7XDS
• run-pickup-stall · sleepInLoopWorkflow - sleep inside loop with steps actually delays each iteration (python) · at 03:05:08Z · abandoned wrun_01M0VE1F35J38MPSCFZMN6YX2P
• run-pickup-stall · WorkflowNotRegisteredError fails the run when workflow does not exist (nextjs-webpack) · at 03:05:16Z · abandoned wrun_01M0VE1QKFX8AWRVN1GKHDE0K9

E2E Test Summary

Summary

	Passed	Failed	Skipped	Total
❌ ▲ Vercel Production	3570	8	742	4320
✅ 💻 Local Development	3922	0	558	4480
✅ 📦 Local Production	3922	0	558	4480
✅ 🐘 Local Postgres	3922	0	558	4480
✅ 🪟 Windows	320	0	0	320
❌ 🌐 Cross-language Conformance	0	9	132	141
✅ vercel-http-transport	817	0	143	960
✅ vercel-multi-region	27	0	0	27
✅ vercel-ws-transport	553	0	87	640
Total	17053	17	2778	19848

Details by Category

❌ ▲ Vercel Production

App	Passed	Failed	Skipped
✅ astro-node	132	0	28
✅ astro-quickjs	132	0	28
✅ example-node	132	0	28
✅ example-quickjs	132	0	28
✅ express-node	132	0	28
✅ express-quickjs	132	0	28
✅ fastify-node	132	0	28
✅ fastify-quickjs	132	0	28
✅ hono-node	132	0	28
✅ hono-quickjs	132	0	28
✅ nest-node	132	0	28
✅ nest-quickjs	132	0	28
✅ nextjs-turbopack-node	157	0	3
✅ nextjs-turbopack-quickjs	157	0	3
✅ nextjs-webpack-node	157	0	3
✅ nextjs-webpack-quickjs	157	0	3
✅ nitro-node	132	0	28
✅ nitro-quickjs	132	0	28
✅ nuxt-node	132	0	28
✅ nuxt-quickjs	132	0	28
❌ python-node	0	8	152
✅ sveltekit-node	151	0	9
✅ sveltekit-quickjs	151	0	9
✅ tanstack-start-node	132	0	28
✅ tanstack-start-quickjs	132	0	28
✅ vite-node	132	0	28
✅ vite-quickjs	132	0	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	141	0	19
✅ nextjs-webpack-canary-quickjs	141	0	19
✅ nextjs-webpack-stable-node	160	0	0
✅ nextjs-webpack-stable-quickjs	160	0	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	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	141	0	19
✅ nextjs-webpack-canary-quickjs	141	0	19
✅ nextjs-webpack-stable-node	160	0	0
✅ nextjs-webpack-stable-quickjs	160	0	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 Postgres

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	141	0	19
✅ nextjs-webpack-canary-quickjs	141	0	19
✅ nextjs-webpack-stable-node	160	0	0
✅ nextjs-webpack-stable-quickjs	160	0	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

✅ 🪟 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	0	9	132

✅ vercel-http-transport

App	Passed	Failed	Skipped
✅ example	132	0	28
✅ express	132	0	28
✅ hono	132	0	28
✅ nextjs-turbopack	157	0	3
✅ nitro	132	0	28
✅ vite	132	0	28

✅ vercel-multi-region

App	Passed	Failed	Skipped
✅ nextjs-turbopack	27	0	0

✅ vercel-ws-transport

App	Passed	Failed	Skipped
✅ example	132	0	28
✅ express	132	0	28
✅ nextjs-turbopack	157	0	3
✅ vite	132	0	28

---

📋 View full workflow run

[github-actions]

📊 Workflow Benchmarks

commit 4834383 · Tue, 25 Aug 2026 03:22:33 GMT · run logs

Backend: vercel · app: nextjs-turbopack

Metric	Scenario	Best (ms)	P75 (ms)	P90 (ms)	P99 (ms)	Samples
TTFS	step	240 (-38%) 💚	1525 🔴 (+39%) 🔻	1574 🔴 (+39%) 🔻	1838 🔴 (+32%) 🔻	30
TTFS	stream	485 (+177%) 🔻	1484 🔴 (+34%) 🔻	1516 🔴 (+34%) 🔻	1567 🔴 (+36%) 🔻	30
TTFS	hook + stream	1712 (+199%) 🔻	1839 🔴 (+35%) 🔻	1897 🔴 (+20%) 🔻	1990 🔴 (-57%) 💚	30
Fan-out TTFS	Promise.all(100 steps)	640 (+2.2%)	2135 (+95%) 🔻	2156 (+39%) 🔻	2292 (-54%) 💚	10
Fan-out TTLS	Promise.all(100 steps)	2612 (+44%) 🔻	4012 (±0%)	4044 (-0.7%)	10348 (+3.9%)	10
STSO	1020 steps (inline)	100 (-11%)	156 (+9.1%)	175 (+5.4%)	281 (+17%) 🔻	1019
WO	1020 steps	157552 (+8.3%)	157552 (+8.3%)	157552 (+8.3%)	157552 (+8.3%)	1
CRTT	first chunk (pooled)	125 (+51%) 🔻	198 (+41%) 🔻	246 (-5.4%)	458 (-35%) 💚	28

Streams

Scenario	CRTT 1st	p75	p90	p99	CDV max	iters
paced control (100/s, 60B)	154 (+38%)	192 (+27%)	257 (-30%)	390 (-42%)	162 (+33%)	10
size sweep (100/s, 160B-12KB)	147 (+31%)	197 (+55%)	323 (+99%)	1023 (+56%)	228 (+111%)	10
replay gateway-gpt-5.4-nano-2000t (1x)	182 (+2%)	146 (-77%)	176 (-92%)	303 (-92%)	211 (-46%)	3
replay eve-gpt-5.6-sol-2000t (1x)	206 (+49%)	163 (+16%)	216 (+14%)	379 (-26%)	221 (-56%)	2
replay eve-gpt-5.6-sol-2000t (2x)	167 (+18%)	208 (+11%)	286 (+6%)	673 (-19%)	290 (+60%)	3

📈 STSO distribution vs main (inline / queue-hop histograms)

1020 steps (inline)

Cumulative STSO time: main 144386ms → this run 156134ms (Δ +11748ms, +8%)

100-150 ms █████████████████┃██████ main 853 this 646 -207
150-200 ms ████░░░░┃ main 138 this 336 +198
200-250 ms ┃ main 19 this 22 +3
250-300 ms ┃ main 4 this 7 +3
300-350 ms ┃ main 5 this 3 -2
350-400 ms ┃ main 0 this 2 +2
400-450 ms ┃ main 0 this 2 +2
600-650 ms ┃ main 0 this 1 +1

📈 CRTT drill-down vs main (RTT distributions & profiles)

variant RTT 1ms→5s+ avg p50 p90 p99 n
control ······▂█▂···· 150.5 (+19%) 135 (+27%) 257 (-30%) 390 (-42%) 3000
sweep ······▂█▂▁▁·· 172.3 (+46%) 145 (+46%) 323 (+99%) 1023 (+56%) 3000
gw 1x ······▃█▁···· 129 (-56%) 125 (+2%) 176 (-92%) 303 (-92%) 5295
eve 1x ······▃█▂···· 138.3 (+14%) 125 (+23%) 216 (+14%) 379 (-26%) 5186
eve 2x ······▁█▃▁··· 171.6 (+16%) 156 (+16%) 286 (+6%) 673 (-19%) 7779

RTT over stream progress (avg per tenth of stream, bars scaled min→max):

control █▇▄▃▂▃▃▁▁▁ 130–189ms
sweep ▃██▅▃▂▁▂▁▂ 133–242ms
gw 1x ▅▄▄█▄▃▂▂▃▁ 120–144ms
eve 1x ▆▂▁▃▁▁██▂▃ 124–166ms
eve 2x ▄▁▃▂▂▆▃▅▆█ 145–207ms

RTT by chunk size (avg per log size bin, ~160B → ~12KB serialized, bars scaled min→max):

sweep █▄▄▄▃▁▄ 170–175ms

Delivery jitter over stream progress (avg positive CDV per tenth of stream, bars scaled min→max):

control ▁▅▃█▄█▄▂▂▁ 40–50ms
sweep ▁▆▅▄▃▆▄▆▃█ 48–65ms
gw 1x ▄▆▃▁▅▂▅█▁▃ 38–43ms
eve 1x ▇▄▁▄▃▃▆▃▂█ 23–32ms
eve 2x █▇▁▂▆▅▄▁▃▆ 24–33ms

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.}

_{The collapsed STSO distribution section above buckets every step gap, split inline (same warm process — pure framework overhead) vs queue-hop (fresh process — dispatch, reinit, replay). █ = main, ┃ = this run, ░ = fill.}

_{The collapsed CRTT drill-down: per-variant RTT histograms (fixed log bins, · = empty) and mean RTT/positive-CDV profile lines over stream progress and chunk size. Histograms, avgs, and profiles merge exactly across runs; p50–p99 are percentile-of-percentiles. Per-index rows live in the artifacts.}

_{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-2000teaf22f5946e7c61f3c65c7006d550df180cfabd4e706254a09f22aec0cfb420d · gateway-gpt-5.4-nano-2000t6f24ac518b6b83ff1d0e85a5fe78230db192716d66a7fc6b2fe022752001d041}

_{🔴 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.}

[VaguelySerious]

AI review: no blocking issues

[TooTallNate]

AI: Approved. I found no blocking issues in the schema-free module split, validation changes, package exports, or bundle-boundary coverage.

[github-actions]

No backport to stable for d62b444 (AI decision).

This is primarily a bundle-size/startup-performance refactor that moves World validation and event-metadata helpers onto new @workflow/world subpath exports and intentionally removes public root-level exports (validateAttributeKey, validateAttributeValue, EVENT_DATA_PAYLOAD_FIELD_BY_EVENT_TYPE, EVENT_DATA_REF_FIELDS) as a deliberate v5 breaking change, carrying a major changeset — exactly the kind of API-surface churn a maintenance line should not take. The two genuine hardening bits (an unknown attribute deletion no longer offsetting a newly added key in the per-run cap accounting in validateAttributeChanges, and prototype-like event type strings such as constructor returning no metadata) are small and could be split out and force-backported on their own if desired. Per the mixed-commit rule, the presence of a breaking refactor makes the whole commit ineligible.

To override, re-run the Backport to stable workflow manually via workflow_dispatch and paste this commit SHA into the ref input:

d62b44473b43e183e71386fe84b33f5e7bb5445c

[NathanColosimo]

Summary

• move runtime-only event metadata and attribute validation onto schema-free @workflow/world subpaths
• keep the public Zod schemas available to hosts without pulling them into the sandbox
• intentionally remove the superseded root-level World validation and event lookup exports as a v5 breaking change
• add regression coverage for both a minimal workflow and normal attribute, hook, and step APIs

Result

For the 97-step benchmark workflow:

• VM bundle: 612,980 B → 26,831 B (-95.6%)
• fresh-context evaluation p50: 10.536 ms → 0.121 ms (-98.9%)
• Zod modules in the benchmark VM bundle: 77 → 0 (workflows that import Zod themselves still include it)

Review scope

Serialized formats are unchanged. Besides the dependency-boundary refactor, this tightens two edge cases: an unknown attribute deletion can no longer offset a newly added key, and prototype-like event type strings safely return no metadata. The @workflow/world changeset is marked major for the intentionally removed public exports; on the current prerelease branch this still produces the next v5 beta.

Validation

• full workspace typecheck
• builders, core, world, and world-vercel package builds/typechecks
• 3,233 package tests across builders, core, world, and world-vercel
• focused workflow-bundle boundary regression tests
• Next/Turbopack and Vite production builds
• clean Codex + Claude autoreview after addressing feedback

[changeset-bot]

🦋 Changeset detected

Latest commit: 4834383

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

This PR includes changesets to release 20 packages

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

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

Project	Deployment	Actions	Updated (UTC)
example-nextjs-workflow-turbopack	Ready	Preview, v0	Aug 25, 2026 2:59am
example-nextjs-workflow-webpack	Ready	Preview, v0	Aug 25, 2026 2:59am
example-workflow	Ready	Preview, v0	Aug 25, 2026 2:59am
workbench-astro-workflow	Ready	Preview, v0	Aug 25, 2026 2:59am
workbench-express-workflow	Ready	Preview, v0	Aug 25, 2026 2:59am
workbench-fastify-workflow	Ready	Preview, v0	Aug 25, 2026 2:59am
workbench-hono-workflow	Ready	Preview, v0	Aug 25, 2026 2:59am
workbench-nestjs-workflow	Ready	Preview, v0	Aug 25, 2026 2:59am
workbench-nitro-workflow	Ready	Preview, v0	Aug 25, 2026 2:59am
workbench-nuxt-workflow	Ready	Preview, v0	Aug 25, 2026 2:59am
workbench-python-workflow	Ready	Preview, v0	Aug 25, 2026 2:59am
workbench-sveltekit-workflow	Ready	Preview, v0	Aug 25, 2026 2:59am
workbench-tanstack-start-workflow	Ready	Preview, v0	Aug 25, 2026 2:59am
workbench-vite-workflow	Ready	Preview, v0	Aug 25, 2026 2:59am
workflow-docs	Ready	Preview, v0	Aug 25, 2026 2:59am
workflow-swc-playground	Ready	Preview, v0	Aug 25, 2026 2:59am
workflow-tarballs	Ready	Preview, v0	Aug 25, 2026 2:59am
workflow-web	Ready	Preview, v0	Aug 25, 2026 2:59am

[github-actions]

🧪 E2E Test Results

❌ Some tests failed

❌ Failed E2E Tests

▲ Vercel Production (8 failed)

python-node (8 failed):

• promiseAllWorkflow | wrun_41M0VDN06C0GJF9R48YSG9WQ30 | 🔍 observability
• sleepingWorkflow | wrun_41M0VDNNN70GXQ8MQGB8DFFBVP | 🔍 observability
• parallelSleepWorkflow | wrun_41M0VDNQ4R0GTSQZ0NV78PS68F | 🔍 observability
• nullByteWorkflow | wrun_41M0VDNXQD0GN74C8N2SH970J4 | 🔍 observability
• cancelRun - cancelling a running workflow | wrun_41M0VDTG7Y0GKNVYEMFAZHAT66 | 🔍 observability
• cancelRun via CLI - cancelling a running workflow | wrun_41M0VDTH470GR3A7GYZW28QRRT | 🔍 observability
• sleepInLoopWorkflow - sleep inside loop with steps actually delays each iteration | wrun_41M0VDTWJP0GGDVNP9TXTDB25Y | 🔍 observability
• resilient start: addTenWorkflow completes when run_created returns 500 | wrun_41M0VDVECE0GW8TM4DBWV2H88X | 🔍 observability

🌐 Cross-language Conformance (9 failed)

python (9 failed):

• deploymentId: 'latest' is a no-op in non-Vercel worlds | wrun_01M0VDY8HAYKF5H611G7HRPJGV
• promiseAllWorkflow | wrun_41M0VDN06C0GJF9R48YSG9WQ30
• sleepingWorkflow | wrun_41M0VDNNN70GXQ8MQGB8DFFBVP
• parallelSleepWorkflow | wrun_41M0VDNQ4R0GTSQZ0NV78PS68F
• nullByteWorkflow | wrun_41M0VDNXQD0GN74C8N2SH970J4
• cancelRun - cancelling a running workflow | wrun_41M0VDTG7Y0GKNVYEMFAZHAT66
• cancelRun via CLI - cancelling a running workflow | wrun_41M0VDTH470GR3A7GYZW28QRRT
• sleepInLoopWorkflow - sleep inside loop with steps actually delays each iteration | wrun_41M0VDTWJP0GGDVNP9TXTDB25Y
• resilient start: addTenWorkflow completes when run_created returns 500 | wrun_41M0VDVECE0GW8TM4DBWV2H88X

⚠️ 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.

• cancelRun via CLI - cancelling a running workflow (nextjs-turbopack)
• hookGetConflictWorkflow - hook.getConflict() resolves with the conflicting run when token is already registered (express)

🛠 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.

34 infra events

• cold-start-warmup · suite warmup (python) · at 02:59:19Z · abandoned wrun_41M0VDKMMW0GH51Y8JG5NNFA53 · (+7 more)
• run-pickup-stall · sleepingWorkflow (python) · at 02:59:35Z · abandoned wrun_41M0VDQ9BQ0GQK2NWX2GHQEVNE
• run-pickup-stall · parallelSleepWorkflow (python) · at 02:59:35Z · abandoned wrun_41M0VDQ9BR0GJ9VX6F75YE9E9Q
• run-pickup-stall · nullByteWorkflow (python) · at 02:59:36Z · abandoned wrun_41M0VDQ9BV0GYFB5RFCSNMCKA8
• run-pickup-stall · promiseAllWorkflow (python) · at 02:59:36Z · abandoned wrun_41M0VDQ9BH0GK9EQXW0CP2ZJCA
• run-pickup-stall · cancelRun - cancelling a running workflow (python) · at 02:59:36Z · abandoned wrun_41M0VDQ9WK0GMVHTNXHTJD781E
• run-pickup-stall · cancelRun - cancelling a running workflow (python) · at 03:00:09Z · abandoned wrun_41M0VDR9R80GNBR3X3RRSVHN07
• run-pickup-stall · nullByteWorkflow (python) · at 03:00:36Z · abandoned wrun_41M0VDS4QY0GH9G06DD4CNPHN0
• run-pickup-stall · promiseAllWorkflow (python) · at 03:00:36Z · abandoned wrun_41M0VDS50Q0GX4S6T0PQTXW632
• run-pickup-stall · sleepingWorkflow (python) · at 03:00:36Z · abandoned wrun_41M0VDS50T0GSG4ZEE82KCJB3M
• run-pickup-stall · parallelSleepWorkflow (python) · at 03:00:36Z · abandoned wrun_41M0VDS4WM0GM7PK0RSWPBVGA0
• cold-start-warmup · suite warmup (tanstack-start) · at 03:00:41Z · abandoned wrun_01M0VDS3CBPAJR0ZH8W972WZZJ
• run-pickup-stall · cancelRun via CLI - cancelling a running workflow (python) · at 03:01:27Z · abandoned wrun_41M0VDS9XE0GTMQHS9QWWG5A2J
• cold-start-warmup · suite warmup (python) · at 03:01:53Z · abandoned wrun_01M0VDRA3CVH1MKDJEYP3V2BDW · (+7 more)
• run-pickup-stall · deploymentId: 'latest' is a no-op in non-Vercel worlds (python) · at 03:02:08Z · abandoned wrun_01M0VDVZ8CVJ5HP9G5FB1A1M3F
• run-pickup-stall · sleepingWorkflow (python) · at 03:02:08Z · abandoned wrun_01M0VDVZ8H5BFT2BTQGSX5M1FZ
• run-pickup-stall · parallelSleepWorkflow (python) · at 03:02:08Z · abandoned wrun_01M0VDVZ8M8XKZTWA23C6T2N7A
• run-pickup-stall · nullByteWorkflow (python) · at 03:02:08Z · abandoned wrun_01M0VDVZ8NTRCFXWR32772DDWJ
• run-pickup-stall · promiseAllWorkflow (python) · at 03:02:08Z · abandoned wrun_01M0VDVZ8DP1T84GQYSC3FST3V
• run-pickup-stall · workflow throws after awaited setAttributes: attribute still persists on the failed run (nuxt) · at 03:03:00Z · abandoned wrun_01M0VDXJ26475QRTXK3E4NYG5E
• run-pickup-stall · deploymentId: 'latest' is a no-op in non-Vercel worlds (python) · at 03:03:08Z · abandoned wrun_01M0VDXSW1STJBAFKY2ZTCJK9G
• run-pickup-stall · sleepingWorkflow (python) · at 03:03:08Z · abandoned wrun_01M0VDXSW5NENDADCH34B3A56A
• run-pickup-stall · promiseAllWorkflow (python) · at 03:03:08Z · abandoned wrun_01M0VDXSW3FS334GPAR9QK29DK
• run-pickup-stall · nullByteWorkflow (python) · at 03:03:08Z · abandoned wrun_01M0VDXSWE2XMMPSNBC595YAX9
• run-pickup-stall · parallelSleepWorkflow (python) · at 03:03:08Z · abandoned wrun_01M0VDXSW8ATGQPPHSTAPYGT45
• run-pickup-stall · cancelRun via CLI - cancelling a running workflow (python) · at 03:03:08Z · abandoned wrun_41M0VDW1SZ0GY2PX4NR4R4Y8X5
• run-pickup-stall · sleepInLoopWorkflow - sleep inside loop with steps actually delays each iteration (python) · at 03:03:08Z · abandoned wrun_41M0VDVWMG0GJ7M15MXRX9SJEM
• run-pickup-stall · cancelRun - cancelling a running workflow (python) · at 03:04:08Z · abandoned wrun_01M0VDZMFMRD0Y1PD7NBT2M72C
• run-pickup-stall · cancelRun via CLI - cancelling a running workflow (python) · at 03:04:08Z · abandoned wrun_01M0VDZMFVFN8Q4FA149CMQ9EQ
• run-pickup-stall · sleepInLoopWorkflow - sleep inside loop with steps actually delays each iteration (python) · at 03:04:08Z · abandoned wrun_01M0VDZMFZ1SM0TW62J5SAFBK3
• run-pickup-stall · cancelRun via CLI - cancelling a running workflow (python) · at 03:04:38Z · abandoned wrun_01M0VE0HVJRVGZC5NAGY22430N
• run-pickup-stall · cancelRun - cancelling a running workflow (python) · at 03:04:38Z · abandoned wrun_01M0VE0HVDHGJS57WFKR4Y7XDS
• run-pickup-stall · sleepInLoopWorkflow - sleep inside loop with steps actually delays each iteration (python) · at 03:05:08Z · abandoned wrun_01M0VE1F35J38MPSCFZMN6YX2P
• run-pickup-stall · WorkflowNotRegisteredError fails the run when workflow does not exist (nextjs-webpack) · at 03:05:16Z · abandoned wrun_01M0VE1QKFX8AWRVN1GKHDE0K9

E2E Test Summary

Summary

	Passed	Failed	Skipped	Total
❌ ▲ Vercel Production	3570	8	742	4320
✅ 💻 Local Development	3922	0	558	4480
✅ 📦 Local Production	3922	0	558	4480
✅ 🐘 Local Postgres	3922	0	558	4480
✅ 🪟 Windows	320	0	0	320
❌ 🌐 Cross-language Conformance	0	9	132	141
✅ vercel-http-transport	817	0	143	960
✅ vercel-multi-region	27	0	0	27
✅ vercel-ws-transport	553	0	87	640
Total	17053	17	2778	19848

Details by Category

❌ ▲ Vercel Production

App	Passed	Failed	Skipped
✅ astro-node	132	0	28
✅ astro-quickjs	132	0	28
✅ example-node	132	0	28
✅ example-quickjs	132	0	28
✅ express-node	132	0	28
✅ express-quickjs	132	0	28
✅ fastify-node	132	0	28
✅ fastify-quickjs	132	0	28
✅ hono-node	132	0	28
✅ hono-quickjs	132	0	28
✅ nest-node	132	0	28
✅ nest-quickjs	132	0	28
✅ nextjs-turbopack-node	157	0	3
✅ nextjs-turbopack-quickjs	157	0	3
✅ nextjs-webpack-node	157	0	3
✅ nextjs-webpack-quickjs	157	0	3
✅ nitro-node	132	0	28
✅ nitro-quickjs	132	0	28
✅ nuxt-node	132	0	28
✅ nuxt-quickjs	132	0	28
❌ python-node	0	8	152
✅ sveltekit-node	151	0	9
✅ sveltekit-quickjs	151	0	9
✅ tanstack-start-node	132	0	28
✅ tanstack-start-quickjs	132	0	28
✅ vite-node	132	0	28
✅ vite-quickjs	132	0	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	141	0	19
✅ nextjs-webpack-canary-quickjs	141	0	19
✅ nextjs-webpack-stable-node	160	0	0
✅ nextjs-webpack-stable-quickjs	160	0	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	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	141	0	19
✅ nextjs-webpack-canary-quickjs	141	0	19
✅ nextjs-webpack-stable-node	160	0	0
✅ nextjs-webpack-stable-quickjs	160	0	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 Postgres

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	141	0	19
✅ nextjs-webpack-canary-quickjs	141	0	19
✅ nextjs-webpack-stable-node	160	0	0
✅ nextjs-webpack-stable-quickjs	160	0	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

✅ 🪟 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	0	9	132

✅ vercel-http-transport

App	Passed	Failed	Skipped
✅ example	132	0	28
✅ express	132	0	28
✅ hono	132	0	28
✅ nextjs-turbopack	157	0	3
✅ nitro	132	0	28
✅ vite	132	0	28

✅ vercel-multi-region

App	Passed	Failed	Skipped
✅ nextjs-turbopack	27	0	0

✅ vercel-ws-transport

App	Passed	Failed	Skipped
✅ example	132	0	28
✅ express	132	0	28
✅ nextjs-turbopack	157	0	3
✅ vite	132	0	28

---

📋 View full workflow run

[github-actions]

📊 Workflow Benchmarks

commit 4834383 · Tue, 25 Aug 2026 03:22:33 GMT · run logs

Backend: vercel · app: nextjs-turbopack

Metric	Scenario	Best (ms)	P75 (ms)	P90 (ms)	P99 (ms)	Samples
TTFS	step	240 (-38%) 💚	1525 🔴 (+39%) 🔻	1574 🔴 (+39%) 🔻	1838 🔴 (+32%) 🔻	30
TTFS	stream	485 (+177%) 🔻	1484 🔴 (+34%) 🔻	1516 🔴 (+34%) 🔻	1567 🔴 (+36%) 🔻	30
TTFS	hook + stream	1712 (+199%) 🔻	1839 🔴 (+35%) 🔻	1897 🔴 (+20%) 🔻	1990 🔴 (-57%) 💚	30
Fan-out TTFS	Promise.all(100 steps)	640 (+2.2%)	2135 (+95%) 🔻	2156 (+39%) 🔻	2292 (-54%) 💚	10
Fan-out TTLS	Promise.all(100 steps)	2612 (+44%) 🔻	4012 (±0%)	4044 (-0.7%)	10348 (+3.9%)	10
STSO	1020 steps (inline)	100 (-11%)	156 (+9.1%)	175 (+5.4%)	281 (+17%) 🔻	1019
WO	1020 steps	157552 (+8.3%)	157552 (+8.3%)	157552 (+8.3%)	157552 (+8.3%)	1
CRTT	first chunk (pooled)	125 (+51%) 🔻	198 (+41%) 🔻	246 (-5.4%)	458 (-35%) 💚	28

Streams

Scenario	CRTT 1st	p75	p90	p99	CDV max	iters
paced control (100/s, 60B)	154 (+38%)	192 (+27%)	257 (-30%)	390 (-42%)	162 (+33%)	10
size sweep (100/s, 160B-12KB)	147 (+31%)	197 (+55%)	323 (+99%)	1023 (+56%)	228 (+111%)	10
replay gateway-gpt-5.4-nano-2000t (1x)	182 (+2%)	146 (-77%)	176 (-92%)	303 (-92%)	211 (-46%)	3
replay eve-gpt-5.6-sol-2000t (1x)	206 (+49%)	163 (+16%)	216 (+14%)	379 (-26%)	221 (-56%)	2
replay eve-gpt-5.6-sol-2000t (2x)	167 (+18%)	208 (+11%)	286 (+6%)	673 (-19%)	290 (+60%)	3

📈 STSO distribution vs main (inline / queue-hop histograms)

1020 steps (inline)

Cumulative STSO time: main 144386ms → this run 156134ms (Δ +11748ms, +8%)

100-150 ms █████████████████┃██████ main 853 this 646 -207
150-200 ms ████░░░░┃ main 138 this 336 +198
200-250 ms ┃ main 19 this 22 +3
250-300 ms ┃ main 4 this 7 +3
300-350 ms ┃ main 5 this 3 -2
350-400 ms ┃ main 0 this 2 +2
400-450 ms ┃ main 0 this 2 +2
600-650 ms ┃ main 0 this 1 +1

📈 CRTT drill-down vs main (RTT distributions & profiles)

variant RTT 1ms→5s+ avg p50 p90 p99 n
control ······▂█▂···· 150.5 (+19%) 135 (+27%) 257 (-30%) 390 (-42%) 3000
sweep ······▂█▂▁▁·· 172.3 (+46%) 145 (+46%) 323 (+99%) 1023 (+56%) 3000
gw 1x ······▃█▁···· 129 (-56%) 125 (+2%) 176 (-92%) 303 (-92%) 5295
eve 1x ······▃█▂···· 138.3 (+14%) 125 (+23%) 216 (+14%) 379 (-26%) 5186
eve 2x ······▁█▃▁··· 171.6 (+16%) 156 (+16%) 286 (+6%) 673 (-19%) 7779

RTT over stream progress (avg per tenth of stream, bars scaled min→max):

control █▇▄▃▂▃▃▁▁▁ 130–189ms
sweep ▃██▅▃▂▁▂▁▂ 133–242ms
gw 1x ▅▄▄█▄▃▂▂▃▁ 120–144ms
eve 1x ▆▂▁▃▁▁██▂▃ 124–166ms
eve 2x ▄▁▃▂▂▆▃▅▆█ 145–207ms

RTT by chunk size (avg per log size bin, ~160B → ~12KB serialized, bars scaled min→max):

sweep █▄▄▄▃▁▄ 170–175ms

Delivery jitter over stream progress (avg positive CDV per tenth of stream, bars scaled min→max):

control ▁▅▃█▄█▄▂▂▁ 40–50ms
sweep ▁▆▅▄▃▆▄▆▃█ 48–65ms
gw 1x ▄▆▃▁▅▂▅█▁▃ 38–43ms
eve 1x ▇▄▁▄▃▃▆▃▂█ 23–32ms
eve 2x █▇▁▂▆▅▄▁▃▆ 24–33ms

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.}

_{The collapsed STSO distribution section above buckets every step gap, split inline (same warm process — pure framework overhead) vs queue-hop (fresh process — dispatch, reinit, replay). █ = main, ┃ = this run, ░ = fill.}

_{The collapsed CRTT drill-down: per-variant RTT histograms (fixed log bins, · = empty) and mean RTT/positive-CDV profile lines over stream progress and chunk size. Histograms, avgs, and profiles merge exactly across runs; p50–p99 are percentile-of-percentiles. Per-index rows live in the artifacts.}

_{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-2000teaf22f5946e7c61f3c65c7006d550df180cfabd4e706254a09f22aec0cfb420d · gateway-gpt-5.4-nano-2000t6f24ac518b6b83ff1d0e85a5fe78230db192716d66a7fc6b2fe022752001d041}

_{🔴 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.}

[VaguelySerious]

AI review: no blocking issues

[TooTallNate]

AI: Approved. I found no blocking issues in the schema-free module split, validation changes, package exports, or bundle-boundary coverage.

[github-actions]

No backport to stable for d62b444 (AI decision).

This is primarily a bundle-size/startup-performance refactor that moves World validation and event-metadata helpers onto new @workflow/world subpath exports and intentionally removes public root-level exports (validateAttributeKey, validateAttributeValue, EVENT_DATA_PAYLOAD_FIELD_BY_EVENT_TYPE, EVENT_DATA_REF_FIELDS) as a deliberate v5 breaking change, carrying a major changeset — exactly the kind of API-surface churn a maintenance line should not take. The two genuine hardening bits (an unknown attribute deletion no longer offsetting a newly added key in the per-run cap accounting in validateAttributeChanges, and prototype-like event type strings such as constructor returning no metadata) are small and could be split out and force-backported on their own if desired. Per the mixed-commit rule, the presence of a breaking refactor makes the whole commit ineligible.

To override, re-run the Backport to stable workflow manually via workflow_dispatch and paste this commit SHA into the ref input:

d62b44473b43e183e71386fe84b33f5e7bb5445c