[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
• add a regression test that builds a real workflow and asserts that Zod is absent

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 VM bundle: 77 → 0

Review scope

This changes dependency boundaries only; workflow behavior and serialized formats are unchanged.

Validation

• builders/core/world package typechecks and builds
• focused builder/runtime tests
• Next/Turbopack and Vite production builds

[changeset-bot]

🦋 Changeset detected

Latest commit: 0e530e2

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

This PR includes changesets to release 21 packages

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

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[vercel]

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

Project	Deployment	Actions	Updated (UTC)
example-nextjs-workflow-turbopack	Ready	Preview	Aug 18, 2026 6:23pm
example-nextjs-workflow-webpack	Ready	Preview	Aug 18, 2026 6:23pm
example-workflow	Ready	Preview	Aug 18, 2026 6:23pm
workbench-astro-workflow	Ready	Preview	Aug 18, 2026 6:23pm
workbench-express-workflow	Ready	Preview	Aug 18, 2026 6:23pm
workbench-fastify-workflow	Ready	Preview	Aug 18, 2026 6:23pm
workbench-hono-workflow	Ready	Preview	Aug 18, 2026 6:23pm
workbench-nestjs-workflow	Ready	Preview	Aug 18, 2026 6:23pm
workbench-nitro-workflow	Ready	Preview	Aug 18, 2026 6:23pm
workbench-nuxt-workflow	Ready	Preview	Aug 18, 2026 6:23pm
workbench-python-workflow	Ready	Preview	Aug 18, 2026 6:23pm
workbench-sveltekit-workflow	Ready	Preview	Aug 18, 2026 6:23pm
workbench-tanstack-start-workflow	Ready	Preview	Aug 18, 2026 6:23pm
workbench-vite-workflow	Ready	Preview	Aug 18, 2026 6:23pm
workflow-docs	Ready	Preview, v0	Aug 18, 2026 6:23pm
workflow-swc-playground	Ready	Preview	Aug 18, 2026 6:23pm
workflow-tarballs	Ready	Preview	Aug 18, 2026 6:23pm
workflow-web	Ready	Preview	Aug 18, 2026 6:23pm

[github-actions]

🧪 E2E Test Results

✅ All tests passed

⚠️ 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.

• outputStreamInsideStepWorkflow - getWritable() called inside step functions (nitro)
• resume-or-start route pattern - resumeHook retried after start() reaches the new run (fastify)

🛠 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.

• run-pickup-stall · addTenWorkflow (tanstack-start) · at 18:23:56Z · abandoned wrun_01M0B1TTW0EHPXWFMGDX824XDM

E2E Test Summary

Summary

	Passed	Failed	Skipped	Total
✅ ▲ Vercel Production	3474	0	738	4212
✅ 💻 Local Development	3810	0	558	4368
✅ 📦 Local Production	3810	0	558	4368
✅ 🐘 Local Postgres	3810	0	558	4368
✅ 🪟 Windows	312	0	0	312
✅ 🌐 Cross-language Conformance	9	0	128	137
✅ vercel-multi-region	27	0	0	27
Total	15252	0	2540	17792

Details by Category

✅ ▲ Vercel Production

App	Passed	Failed	Skipped
✅ astro-node	128	0	28
✅ astro-quickjs	128	0	28
✅ example-node	128	0	28
✅ example-quickjs	128	0	28
✅ express-node	128	0	28
✅ express-quickjs	128	0	28
✅ fastify-node	128	0	28
✅ fastify-quickjs	128	0	28
✅ hono-node	128	0	28
✅ hono-quickjs	128	0	28
✅ nest-node	128	0	28
✅ nest-quickjs	128	0	28
✅ nextjs-turbopack-node	153	0	3
✅ nextjs-turbopack-quickjs	153	0	3
✅ nextjs-webpack-node	153	0	3
✅ nextjs-webpack-quickjs	153	0	3
✅ nitro-node	128	0	28
✅ nitro-quickjs	128	0	28
✅ nuxt-node	128	0	28
✅ nuxt-quickjs	128	0	28
✅ python-node	8	0	148
✅ sveltekit-node	147	0	9
✅ sveltekit-quickjs	147	0	9
✅ tanstack-start-node	128	0	28
✅ tanstack-start-quickjs	128	0	28
✅ vite-node	128	0	28
✅ vite-quickjs	128	0	28

✅ 💻 Local Development

App	Passed	Failed	Skipped
✅ astro-stable-node	130	0	26
✅ astro-stable-quickjs	130	0	26
✅ express-stable-node	130	0	26
✅ express-stable-quickjs	130	0	26
✅ fastify-stable-node	130	0	26
✅ fastify-stable-quickjs	130	0	26
✅ hono-stable-node	130	0	26
✅ hono-stable-quickjs	130	0	26
✅ nest-stable-node	130	0	26
✅ nest-stable-quickjs	130	0	26
✅ nextjs-turbopack-canary-node	137	0	19
✅ nextjs-turbopack-canary-quickjs	137	0	19
✅ nextjs-turbopack-stable-node	156	0	0
✅ nextjs-turbopack-stable-quickjs	156	0	0
✅ nextjs-webpack-canary-node	137	0	19
✅ nextjs-webpack-canary-quickjs	137	0	19
✅ nextjs-webpack-stable-node	156	0	0
✅ nextjs-webpack-stable-quickjs	156	0	0
✅ nitro-stable-node	130	0	26
✅ nitro-stable-quickjs	130	0	26
✅ nuxt-stable-node	130	0	26
✅ nuxt-stable-quickjs	130	0	26
✅ sveltekit-stable-node	149	0	7
✅ sveltekit-stable-quickjs	149	0	7
✅ tanstack-start-node	130	0	26
✅ tanstack-start-quickjs	130	0	26
✅ vite-stable-node	130	0	26
✅ vite-stable-quickjs	130	0	26

✅ 📦 Local Production

App	Passed	Failed	Skipped
✅ astro-stable-node	130	0	26
✅ astro-stable-quickjs	130	0	26
✅ express-stable-node	130	0	26
✅ express-stable-quickjs	130	0	26
✅ fastify-stable-node	130	0	26
✅ fastify-stable-quickjs	130	0	26
✅ hono-stable-node	130	0	26
✅ hono-stable-quickjs	130	0	26
✅ nest-stable-node	130	0	26
✅ nest-stable-quickjs	130	0	26
✅ nextjs-turbopack-canary-node	137	0	19
✅ nextjs-turbopack-canary-quickjs	137	0	19
✅ nextjs-turbopack-stable-node	156	0	0
✅ nextjs-turbopack-stable-quickjs	156	0	0
✅ nextjs-webpack-canary-node	137	0	19
✅ nextjs-webpack-canary-quickjs	137	0	19
✅ nextjs-webpack-stable-node	156	0	0
✅ nextjs-webpack-stable-quickjs	156	0	0
✅ nitro-stable-node	130	0	26
✅ nitro-stable-quickjs	130	0	26
✅ nuxt-stable-node	130	0	26
✅ nuxt-stable-quickjs	130	0	26
✅ sveltekit-stable-node	149	0	7
✅ sveltekit-stable-quickjs	149	0	7
✅ tanstack-start-node	130	0	26
✅ tanstack-start-quickjs	130	0	26
✅ vite-stable-node	130	0	26
✅ vite-stable-quickjs	130	0	26

✅ 🐘 Local Postgres

App	Passed	Failed	Skipped
✅ astro-stable-node	130	0	26
✅ astro-stable-quickjs	130	0	26
✅ express-stable-node	130	0	26
✅ express-stable-quickjs	130	0	26
✅ fastify-stable-node	130	0	26
✅ fastify-stable-quickjs	130	0	26
✅ hono-stable-node	130	0	26
✅ hono-stable-quickjs	130	0	26
✅ nest-stable-node	130	0	26
✅ nest-stable-quickjs	130	0	26
✅ nextjs-turbopack-canary-node	137	0	19
✅ nextjs-turbopack-canary-quickjs	137	0	19
✅ nextjs-turbopack-stable-node	156	0	0
✅ nextjs-turbopack-stable-quickjs	156	0	0
✅ nextjs-webpack-canary-node	137	0	19
✅ nextjs-webpack-canary-quickjs	137	0	19
✅ nextjs-webpack-stable-node	156	0	0
✅ nextjs-webpack-stable-quickjs	156	0	0
✅ nitro-stable-node	130	0	26
✅ nitro-stable-quickjs	130	0	26
✅ nuxt-stable-node	130	0	26
✅ nuxt-stable-quickjs	130	0	26
✅ sveltekit-stable-node	149	0	7
✅ sveltekit-stable-quickjs	149	0	7
✅ tanstack-start-node	130	0	26
✅ tanstack-start-quickjs	130	0	26
✅ vite-stable-node	130	0	26
✅ vite-stable-quickjs	130	0	26

✅ 🪟 Windows

App	Passed	Failed	Skipped
✅ nextjs-turbopack-node	156	0	0
✅ nextjs-turbopack-quickjs	156	0	0

✅ 🌐 Cross-language Conformance

App	Passed	Failed	Skipped
✅ python	9	0	128

✅ vercel-multi-region

App	Passed	Failed	Skipped
✅ nextjs-turbopack	27	0	0

---

📋 View full workflow run

[github-actions]

📊 Workflow Benchmarks

commit 0e530e2 · Tue, 18 Aug 2026 18:39:39 GMT · run logs

Backend: vercel · app: nextjs-turbopack

Metric	Scenario	Best (ms)	P75 (ms)	P90 (ms)	P99 (ms)	Samples
TTFS	step	235 (+4.4%)	1250 🔴 (+10%)	1312 🔴 (+11%)	1409 🔴 (-14%)	30
TTFS	stream	163 (-28%) 💚	1278 🔴 (+8.1%)	1290 🔴 (+6.3%)	1295 🔴 (-31%) 💚	30
TTFS	hook + stream	436 (+14%)	1539 🔴 (+13%)	1567 🔴 (+12%)	1731 🔴 (+20%) 🔻	30
Fan-out TTFS	Promise.all(100 steps)	924 (-26%) 💚	1377 (-43%) 💚	2528 (-2.4%)	2946 (+9.6%)	10
Fan-out TTLS	Promise.all(100 steps)	5246 (-24%) 💚	7905 (-7.8%)	8026 (-9.1%)	8087 (-9.6%)	10
STSO	1020 steps (inline)	122 (-24%) 💚	211 (-27%) 💚	234 (-32%) 💚	319 (-36%) 💚	1019
WO	1020 steps	205760 (-26%) 💚	205760 (-26%) 💚	205760 (-26%) 💚	205760 (-26%) 💚	1
CRTT	first chunk (pooled)	77 (-18%) 💚	102 (-29%) 💚	191 (±0%)	415 (+10%)	28

Streams

Scenario	wr c/s	rd c/s	wr KiB/s	rd KiB/s	CRTT 1st	p75	p90	p99	CDV max	iters
paced control (100/s, 60B)	100 (±0%)	99.8 (+3%)	5 (±0%)	5 (+3%)	98 (-19%)	111 (-50%)	143 (-71%)	467 (-63%)	97.5 (-57%)	10
size sweep (100/s, 160B-12KB)	100 (±0%)	101 (+3%)	334 (±0%)	337 (+3%)	97 (-33%)	119 (-53%)	177 (-74%)	338 (-73%)	111 (-74%)	10
replay gateway-gpt-5.4-nano-2000t (1x)	89.2 (±0%)	89.2 (±0%)	16.2 (±0%)	16.2 (-1%)	86 (-29%)	130 (-48%)	324 (-86%)	929 (-76%)	596 (-26%)	3
replay eve-gpt-5.6-sol-2000t (1x)	54.7 (±0%)	54.6 (-4%)	355 (±0%)	355 (-4%)	100 (-24%)	111 (-49%)	140 (-79%)	249 (-95%)	199 (-94%)	2
replay eve-gpt-5.6-sol-2000t (2x)	109 (±0%)	109 (±0%)	710 (±0%)	708 (±0%)	107 (-11%)	149 (-36%)	198 (-41%)	500 (-23%)	327 (-12%)	3

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

1020 steps (inline)

Cumulative STSO time: main 277417ms → this run 205551ms (Δ -71866ms, -26%)

100-150 ms  ┃                         main   0  this   8    +8
150-200 ms  ██░░░░░░░░░░░░░░░░░░░░░┃  main  47  this 602  +555
200-250 ms  █████████████┃            main 357  this 349    -8
250-300 ms  █┃██████████████          main 397  this  42  -355
300-350 ms  ┃████                     main 126  this  14  -112
350-400 ms  ┃█                        main  50  this   4   -46
400-450 ms  ┃                         main  23  this   0   -23
450-500 ms  ┃                         main   9  this   0    -9
500-550 ms  ┃                         main   4  this   0    -4
550-600 ms  ┃                         main   2  this   0    -2
600-650 ms  ┃                         main   2  this   0    -2
700-750 ms  ┃                         main   1  this   0    -1
850-900 ms  ┃                         main   1  this   0    -1

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

variant  RTT 1ms→5s+             avg         p50         p90         p99     n
control  ·····▁█▅▁····   99.6 (-48%)   90 (-37%)  143 (-71%)  467 (-63%)  3000
sweep    ······█▇▁····  102.2 (-52%)   97 (-32%)  177 (-74%)  338 (-73%)  3000
gw 1x    ·····▁█▅▁▁▁··  122.5 (-59%)   93 (-39%)  324 (-86%)  929 (-76%)  5295
eve 1x   ·····▁█▅▁····   94.3 (-72%)   86 (-38%)  140 (-79%)  249 (-95%)  5186
eve 2x   ·····▁▅█▂▁···    130 (-35%)  116 (-34%)  198 (-41%)  500 (-23%)  7779

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

control  ▅█▃▄▁▁▂▁▁▃  87–132ms
sweep    ▅▃▃▁█▆▄▂▁▃  92–119ms
gw 1x    ▆▃▂█▁▃▂▁▁▃  89–204ms
eve 1x   ▆▂▃▂▂█▆█▅▁  84–106ms
eve 2x   █▁▂▂▁▂▃▇▃▂  108–183ms

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

sweep  █▆▆▄▂▁▁  99–106ms

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

control  ▇█▄▇▅▁▄▃▄▇  23–31ms
sweep    ▄▁▄▄█▅▄▅▃▃  34–56ms
gw 1x    █▃█▃▂▆▁▁▂▅  26–38ms
eve 1x   ▃▁▁▁▃▄█▃▄▄  20–29ms
eve 2x   █▂▁▁▃▃▃▃▃▃  22–38ms

ℹ️ Metric definitions & methodology

_{Streams: writer/reader sustained rates (steady window, 10% trimmed each side), 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-2000t eaf22f5946e7c61f3c65c7006d550df180cfabd4e706254a09f22aec0cfb420d · gateway-gpt-5.4-nano-2000t 6f24ac518b6b83ff1d0e85a5fe78230db192716d66a7fc6b2fe022752001d041}

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

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

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