[core] Retain workflow VMs across hooks by NathanColosimo · Pull Request #3576 · vercel/workflow

NathanColosimo · 2026-08-15T03:44:26Z

Summary

retain a workflow VM across safe step boundaries that also contain hooks
generation-guard step and hook suspension signals so stale callbacks cannot demote a resumed session
include hook metadata and abort-reason serialization in the same passivity gate as step inputs
replay hook-only, wait, attribute, unsafe-serialization, and WORKFLOW_RETAINED_VM=0 boundaries

Why

Spec 6 event logs are monotone prefixes. A hook_received event that lands after the VM consumed its prefix extends that prefix on the next delta without invalidating the retained session, so an open hook does not itself require replay.

Retention still requires a step boundary. Inline step bodies keep awaiting an accepted step_started ownership claim when an open hook can wake a competing invocation, and resume keeps the existing exact-prefix extension check.

Verification

pnpm --filter @workflow/core test — 2,124 passed, 3 expected failures
pnpm typecheck — 43 tasks passed
pnpm turbo build --filter=@workflow/core... — 7 tasks passed
pnpm lint — passed with baseline advisory diagnostics
pnpm changeset status --since=origin/codex/replay-lazy-source-bundles

vercel · 2026-08-15T03:44:30Z

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changeset-bot · 2026-08-15T03:44:31Z

🦋 Changeset detected

Latest commit: a2bbf72

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

This PR includes changesets to release 16 packages

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

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

github-actions · 2026-08-15T03:44:44Z

🧪 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.

startFromWorkflow - calling start() directly inside a workflow function with hook communication (nest)

🛠 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 06:19:11Z · abandoned wrun_01M0215KWW8NB4MG3KVVE172KT
run-pickup-stall · deploymentId: 'latest' is a no-op in non-Vercel worlds (tanstack-start) · at 06:20:03Z · abandoned wrun_01M02176BBH279TB3CT77Q9PQY
run-pickup-stall · addTenWorkflow (vite) · at 06:20:13Z · abandoned wrun_01M0217FZJ0584HTEZF1R5H7S6
run-pickup-stall · promiseAllWorkflow (tanstack-start) · at 06:20:36Z · abandoned wrun_01M02186A6VPJ9JD180PVF213Y
run-pickup-stall · promiseAllWorkflow (vite) · at 06:21:22Z · abandoned wrun_01M0219KE3JR00Y9W5FN2WAZK2
run-pickup-stall · promiseAnyWorkflow (tanstack-start) · at 06:21:29Z · abandoned wrun_01M0219T46T1A9PQ6G4S1RCVVN

E2E Test Summary

Summary

	Passed	Skipped	Total
✅ ▲ Vercel Production	3474	738	4212
✅ 💻 Local Development	3380	520	3900
✅ 📦 Local Production	3810	558	4368
✅ 🐘 Local Postgres	3810	558	4368
✅ 🪟 Windows	312	0	312
✅ 🌐 Cross-language Conformance	9	128	137
✅ vercel-multi-region	27	0	27
Total	14822	2502	17324

Details by Category

✅ ▲ Vercel Production

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

✅ 💻 Local Development

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

✅ 📦 Local Production

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

✅ 🐘 Local Postgres

App	Passed	Skipped
✅ astro-stable-node	130	26
✅ astro-stable-quickjs	130	26
✅ express-stable-node	130	26
✅ express-stable-quickjs	130	26
✅ fastify-stable-node	130	26
✅ fastify-stable-quickjs	130	26
✅ hono-stable-node	130	26
✅ hono-stable-quickjs	130	26
✅ nest-stable-node	130	26
✅ nest-stable-quickjs	130	26
✅ nextjs-turbopack-canary-node	137	19
✅ nextjs-turbopack-canary-quickjs	137	19
✅ nextjs-turbopack-stable-node	156	0
✅ nextjs-turbopack-stable-quickjs	156	0
✅ nextjs-webpack-canary-node	137	19
✅ nextjs-webpack-canary-quickjs	137	19
✅ nextjs-webpack-stable-node	156	0
✅ nextjs-webpack-stable-quickjs	156	0
✅ nitro-stable-node	130	26
✅ nitro-stable-quickjs	130	26
✅ nuxt-stable-node	130	26
✅ nuxt-stable-quickjs	130	26
✅ sveltekit-stable-node	149	7
✅ sveltekit-stable-quickjs	149	7
✅ tanstack-start-node	130	26
✅ tanstack-start-quickjs	130	26
✅ vite-stable-node	130	26
✅ vite-stable-quickjs	130	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 · 2026-08-15T03:44:44Z

📊 Workflow Benchmarks

commit a2bbf72 · Sat, 15 Aug 2026 06:37:21 GMT · run logs

Backend: vercel · app: nextjs-turbopack

Metric	Scenario	Best (ms)	P75 (ms)	P90 (ms)	P99 (ms)	Samples
TTFS	step	124 (-45%) 💚	1152 🔴 (±0%)	1199 🔴 (-1.0%)	1273 🔴 (-6.1%)	30
TTFS	stream	1095 (+366%) 🔻	1142 🔴 (-4.4%)	1147 🔴 (-9.4%)	1664 🔴 (+23%) 🔻	30
TTFS	hook + stream	1378 (+231%) 🔻	1450 🔴 (+1.7%)	1499 🔴 (+3.0%)	1841 🔴 (+19%) 🔻	30
Fan-out TTFS	Promise.all(100 steps)	886 (-33%) 💚	1196 (-53%) 💚	1203 (-55%) 💚	2090 (-35%) 💚	10
Fan-out TTLS	Promise.all(100 steps)	10016 (-7.8%)	12025 (-89%) 💚	13776 (-93%) 💚	14352 (-92%) 💚	10
STSO	1020 steps (inline)	125 (-19%) 💚	396 (-20%) 💚	426 (-24%) 💚	476 (-39%) 💚	1018
STSO	1020 steps (queue-hop)	2325	2325	2325	2325	1
WO	1020 steps	353253 (-15%)	353253 (-15%)	353253 (-15%)	353253 (-15%)	1
CRTT	first chunk (pooled)	86 (-11%)	117 (-25%) 💚	134 (-43%) 💚	164 (-43%) 💚	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%)	100 (-2%)	5 (±0%)	5 (-2%)	99.5 (-26%)	126 (-58%)	155 (-85%)	269 (-82%)	123 (-41%)	10
size sweep (100/s, 160B-12KB)	100 (±0%)	101 (+1%)	334 (±0%)	336 (+1%)	97.5 (-16%)	160 (-53%)	388 (-49%)	1097 (-13%)	154 (-51%)	10
replay gateway-gpt-5.4-nano-2000t (1x)	89.2 (±0%)	89.2 (±0%)	16.2 (±0%)	16.2 (-1%)	91 (-9%)	116 (-17%)	151 (-22%)	649 (-26%)	216 (-40%)	3
replay eve-gpt-5.6-sol-2000t (1x)	54.7 (±0%)	54.7 (±0%)	355 (±0%)	355 (±0%)	95 (-43%)	124 (-30%)	183 (-79%)	738 (-80%)	586 (-70%)	2
replay eve-gpt-5.6-sol-2000t (2x)	109 (±0%)	109 (+1%)	710 (±0%)	711 (+1%)	100 (-21%)	139 (-52%)	180 (-73%)	362 (-81%)	262 (-74%)	3

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

1020 steps (inline)

Cumulative STSO time: main 413585ms → this run 350822ms (Δ -62763ms, -15%)

  100-150 ms  ┃                         main   0  this   8    +8
  150-200 ms  █┃████                    main  69  this  25   -44
  200-250 ms  █████┃███                 main 102  this  62   -40
  250-300 ms  █████░░░░░░░░░░░░┃        main  52  this 203  +151
  300-350 ms  ██████████████░░░░░┃      main 154  this 218   +64
  350-400 ms  █████████████████░░░░░░┃  main 193  this 267   +74
  400-450 ms  ███████░░░░░░░░░░┃        main  80  this 196  +116
  450-500 ms  ██┃████████               main 118  this  34   -84
  500-550 ms  ┃███████████              main 135  this   3  -132
  550-600 ms  ┃████                     main  61  this   1   -60
  600-650 ms  ┃█                        main  19  this   0   -19
  650-700 ms  ┃                         main  13  this   0   -13
  700-750 ms  ┃                         main   9  this   0    -9
  750-800 ms  ┃                         main   4  this   0    -4
  800-850 ms  ┃                         main   3  this   0    -3
  850-900 ms  ┃                         main   2  this   0    -2
 950-1000 ms  ┃                         main   1  this   0    -1
1200-1250 ms  ┃                         main   1  this   0    -1
3000-3050 ms  ┃                         main   0  this   1    +1
3150-3200 ms  ┃                         main   1  this   0    -1
3600-3650 ms  ┃                         main   1  this   0    -1
3650-3700 ms  ┃                         main   1  this   0    -1

1020 steps (queue-hop)

Cumulative STSO time: 2325ms over 1 samples

_{No main baseline with raw samples yet — showing this run's distribution on its own; the diff appears once a run on main has recorded them.}

2200-2400 ms  ████████████████████████  steps 1

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

variant  RTT 1ms→5s+             avg         p50         p90          p99     n
control  ······▇█▁····  106.7 (-56%)  100 (-35%)  155 (-85%)   269 (-82%)  3000
sweep    ······▇█▂▁▁··  142.3 (-32%)  102 (-22%)  388 (-49%)  1097 (-13%)  3000
gw 1x    ·····▁█▆▁▁···  104.4 (-20%)   97 (-16%)  151 (-22%)   649 (-26%)  5295
eve 1x   ·····▁█▆▁▁···  108.3 (-58%)   89 (-23%)  183 (-79%)   738 (-80%)  5186
eve 2x   ·····▁▅█▁▁···  120.9 (-55%)  112 (-36%)  180 (-73%)   362 (-81%)  7779

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

control  ▆█▆▃▂▂▄▂▄▁  100–116ms
sweep    ▁▁▃▆█▇▅▁▁▁  106–209ms
gw 1x    ▁▃▂▁▃▂▁▂█▂  93–145ms
eve 1x   █▁▃▂▁▂▂▂▂▁  86–190ms
eve 2x   ▃▄▃▄▁▃▄█▄▄  97–155ms

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

sweep  ▆██▄▁▂▃  139–145ms

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

control  ▁█▆▄▄▃▆▆▅▂  28–40ms
sweep    ▁▄▄█▃▅▂▂▂▁  42–77ms
gw 1x    ▂█▄▁▆▅▄▆▆▆  25–35ms
eve 1x   █▁▂▂▂▂▃▃▃▄  21–37ms
eve 2x   ▃▃▁▄▃▅▅▆▂█  21–33ms

📜 Previous results (1)

`83a5811`

Sat, 15 Aug 2026 04:04:56 GMT · run logs

vercel / nextjs-turbopack

Metric	Scenario	Best (ms)	P75 (ms)	P90 (ms)	P99 (ms)	Samples
TTFS	step	1284 (+466%) 🔻	1464 🔴 (+28%) 🔻	1485 🔴 (+23%) 🔻	1792 🔴 (+32%) 🔻	30
TTFS	stream	202 (-14%)	1458 🔴 (+22%) 🔻	1467 🔴 (+16%) 🔻	1533 🔴 (+13%)	30
TTFS	hook + stream	1562 (+275%) 🔻	1725 🔴 (+21%) 🔻	1770 🔴 (+22%) 🔻	1938 🔴 (+25%) 🔻	30
Fan-out TTFS	Promise.all(100 steps)	1070 (-19%) 💚	2732 (+6.2%)	2837 (+5.0%)	3042 (-5.0%)	10
Fan-out TTLS	Promise.all(100 steps)	10158 (-6.5%)	12315 (-89%) 💚	12919 (-93%) 💚	15274 (-92%) 💚	10
STSO	1020 steps (inline)	112 (-27%) 💚	290 (-42%) 💚	339 (-39%) 💚	486 (-38%) 💚	1019
WO	1020 steps	250532 (-40%) 💚	250532 (-40%) 💚	250532 (-40%) 💚	250532 (-40%) 💚	1
CRTT	first chunk (pooled)	74 (-24%) 💚	108 (-30%) 💚	156 (-34%) 💚	250 (-13%)	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%)	101 (-1%)	5 (±0%)	5.1 (±0%)	102 (-24%)	110 (-63%)	155 (-85%)	322 (-78%)	91 (-56%)	10
size sweep (100/s, 160B-12KB)	100 (±0%)	101 (+1%)	334 (±0%)	335 (+1%)	94.5 (-19%)	121 (-65%)	170 (-78%)	520 (-59%)	110 (-65%)	10
replay gateway-gpt-5.4-nano-2000t (1x)	89.2 (±0%)	89.2 (±0%)	16.2 (±0%)	16.2 (-1%)	111 (+11%)	105 (-25%)	134 (-31%)	306 (-65%)	132 (-64%)	3
replay eve-gpt-5.6-sol-2000t (1x)	54.7 (±0%)	54.7 (±0%)	355 (±0%)	355 (±0%)	97 (-42%)	114 (-36%)	150 (-82%)	335 (-91%)	299 (-85%)	2
replay eve-gpt-5.6-sol-2000t (2x)	109 (±0%)	110 (+1%)	710 (±0%)	712 (+1%)	102 (-19%)	121 (-58%)	171 (-75%)	362 (-81%)	248 (-75%)	3

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.}

github-actions · 2026-08-15T03:48:13Z

Sim World

Simulated world deterministic testing for races. Traces

🟠 Mint-ordered log — 3 fail of 41 total

log=mint-ordered · fence=per-spec

scenario	outcome	events	virt	replay	violations
✅ `smoke-no-steps`	completed	3	0ms	ok	0
✅ `smoke-one-step`	completed	6	0ms	ok	0
✅ `hook-at-step-started`	completed	12	0ms	ok	0
✅ `hook-at-step-completed`	completed	12	0ms	ok	0
✅ `hook-at-hook-created`	completed	12	0ms	ok	0
✅ `deadline-hook-wins`	completed	7	1.0h	ok	0
✅ `deadline-expires`	completed	7	1.0h	ok	0
✅ `long-sleep`	completed	11	30.0d	ok	0
✅ `hook-never-arrives`	stalled	3	0ms	skipped	0
✅ `step-retries-twice`	completed	10	2.0s	ok	0
✅ `parallel-steps`	completed	9	0ms	ok	0
✅ `hook-on-execution-state`	completed	12	0ms	ok	0
✅ `peek-hook-before-branch`	completed	12	0ms	ok	0
✅ `peek-hook-after-branch`	completed	12	0ms	ok	0
✅ `peek-hook-at-registration`	completed	12	0ms	ok	0
✅ `race-hook-before-probe`	completed	12	0ms	ok	0
✅ `race-hook-after-probe`	completed	12	0ms	ok	0
✅ `race-duplicate-delivery`	completed	13	0ms	ok	0
✅ `attr-hook-before-step`	completed	11	0ms	ok	0
✅ `attr-hook-after-step`	completed	11	0ms	ok	0
✅ `attr-from-step-body`	completed	13	0ms	ok	0
✅ `fork-hook-after-timeout`	completed	14	1.0m	ok	0
✅ `fork-hook-before-timeout`	completed	14	1.0m	ok	0
✅ `count-hook-after-timeout`	completed	17	1.0m	ok	0
✅ `count-hook-before-timeout`	completed	20	1.0m	ok	0
✅ `stale-read-step-count-fork`	completed	20	1.0m	ok	0
✅ `stale-read-equal-step-counts`	completed	14	1.0m	ok	0
✅ `step-vs-step-fork`	completed	12	0ms	ok	0
✅ `step-vs-step-fork-fenced`	completed	12	0ms	ok	0
✅ `fence-catches-benign-direction`	completed	12	5ms	ok	0
❌ `in-flight-before-decision`	failed	9	1.0m	MISMATCH	1
❌ `in-flight-before-decision-counted`	failed	9	1.0m	MISMATCH	1
❌ `in-flight-after-decision`	failed	9	1.0m	MISMATCH	1
✅ `stale-read-step-count-fork-fenced`	completed	20	1.0m	ok	0
✅ `fork-hook-wins`	completed	13	1.0m	ok	0
✅ `fork-timeout-wins`	completed	13	1.0m	ok	0
✅ `unclaimed-payload-under-fork`	completed	17	1.0m	ok	0
✅ `claimed-payload-under-fork`	completed	17	1.0m	ok	0
✅ `writers-independent-step-bodies`	completed	12	0ms	ok	0
✅ `writers-scripted-tempo`	completed	12	0ms	ok	0
✅ `cancel-mid-step`	cancelled	7	0ms	skipped	0

Full trace: world-sim-mint.txt

🟢 Append-only log — 0 fail of 41 total

log=append-only · fence=per-spec

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

Full trace: world-sim-append-only.txt

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NathanColosimo force-pushed the codex/retain-vm-with-hooks branch from 83a5811 to 8c5846c Compare August 15, 2026 05:07

NathanColosimo changed the base branch from main to codex/replay-lazy-source-bundles August 15, 2026 05:08

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Retain workflow VMs across hooks

a2bbf72

NathanColosimo force-pushed the codex/retain-vm-with-hooks branch from 362633e to a2bbf72 Compare August 15, 2026 06:13

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[core] Retain workflow VMs across hooks - #3576

[core] Retain workflow VMs across hooks#3576
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codex/replay-lazy-source-bundlesfrom
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🧪 E2E Test Results

⚠️ Flaky E2E Tests (passed on retry)

🛠 Infra Events (absorbed by the harness)

E2E Test Summary

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📊 Workflow Benchmarks

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Sim World

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NathanColosimo commented Aug 15, 2026 •

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