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[core] Log pending consumers in divergence diagnostics - #4021

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Sep 10, 2026
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Why

A production run failed with CORRUPTED_EVENT_LOG after four divergences on one wait_created event, and diagnosing it took hours because the runtime did not say the decisive facts: what was holding that event's ordinal, which pass of which invocation diverged, and whether every divergence hit the same slot. This PR adds those to the existing messages and logs. No behavior change.

What

1. Name what holds the ordinal (@workflow/core)

Step, wait and hook correlation ids share one ULID draw per entity (step_<ulid>, wait_<ulid>, hook_<ulid>). When a replay cannot consume an event, the ReplayDivergenceError message now appends the pending invocation holding that ULID body and a snapshot of the consumer's walk, on both the Replay could not consume event and Replay finished without consuming event paths. The leading sentence is unchanged. New EventsConsumer.describe() supplies the snapshot instead of reaching into private fields.

Replay could not consume event: eventType=wait_created, correlationId=wait_01K…, eventId=evnt_01K…. pending at this id: step drainStep (step_01K…). consumer: index=41, length=44, parked=0, lastConsumed=evnt_01K…

2. Say which pass of which invocation diverged (@workflow/core)

The Workflow replay diverged; queueing a recovery replay… WARN and the terminal Error while running workflow log gain loopIteration, servedByRetainedSession, eventLogState, eventLogLength, eventLogLastEventId, cursor, hasHookInput, hasWaitContinuation, isRecoveryReplay, setupSource, and divergenceEventIds. All in scope already, no network calls.

The console renderer (log-format.ts) listed errorMessage as a well-known field but never rendered it, so any warn/error whose message had no stack body silently dropped the error text. That is how the production WARN lost the divergence text. It now renders as an error row whenever neither the framing nor the body carries it. The terminal Error while running workflow log had the same gap (its errorStack is dropped by design and the message has no body), so it now passes errorMessage too.

3. Divergence history on the recovery message (@workflow/world, @workflow/core)

replayDivergence on the queue payload gains an optional eventIds: string[], accumulated across hops and capped at the recovery budget + 1. Parsed with .catch(undefined) so a malformed value degrades to "no history" instead of failing every delivery of the message. The terminal CorruptedEventLogError message lists it:

Workflow replay diverged 4 times after 3 recovery replays; latest divergent event was evnt_…303; divergent event ids: evnt_…303, evnt_…303, evnt_…303, evnt_…303. Last divergence: …

Tests

  • replay-divergence.test.ts: drives a replay where the body calls useStep('drainStep') while the log holds wait_created under the same ULID body; asserts the message names the step and the consumer snapshot. Plus unit tests for the ordinal lookup and describe().
  • runtime.test.ts: the existing divergence test now spies on console output and asserts the WARN fields, the history on the recovery message, and the terminal message listing all ids.
  • log-format.test.ts / logger.test.ts: new test for the WARN shape; two snapshots updated because they were pinning the dropped errorMessage.
  • queue.test.ts (@workflow/world): round-trip, absent, and malformed eventIds.

🤖 Generated with Claude Code

…stics

A replay divergence is reported as "could not consume event X" with
nothing about why nobody could. The usual reason is that the pending
invocation holding the event's ordinal is a different kind of entity
(a step where the log recorded a wait), and the message now says so,
along with where the consumer's walk stands. The recovery WARN and the
terminal CorruptedEventLogError log carry which pass of which
invocation diverged (loopIteration, retained-VM vs cold replay, event
log length/tail/cursor, hookInput/waitContinuation presence, setup
source), the recovery message accumulates a bounded history of
divergent event ids that the terminal message prints, and the console
renderer no longer drops `errorMessage` when the message itself does
not carry the text.

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
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🦋 Changeset detected

Latest commit: c6f7d03

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

This PR includes changesets to release 20 packages
Name Type
@workflow/core Patch
@workflow/world 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/world-local Patch
@workflow/world-postgres Patch
@workflow/world-vercel Patch
@workflow/astro Patch
@workflow/nest Patch
@workflow/rollup Patch
@workflow/sveltekit Patch
@workflow/vite Patch
@workflow/nuxt Patch

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

Project Deployment Actions Updated
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🧪 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.

  • addTenWorkflow (hono) — flaked in 2 jobs
  • cancelRun via CLI - cancelling a running workflow (nextjs-turbopack)
  • deploymentId: 'latest' is a no-op in non-Vercel worlds (tanstack-start)
  • deploymentId: 'latest' is a no-op in non-Vercel worlds (vite)

🛠 Infra Events (absorbed by the harness)

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

  • cold-start-warmup · suite warmup (tanstack-start) · at 21:15:29Z · abandoned wrun_01M26JS2SK5S75JWET5C413764
  • run-pickup-stall · hookCleanupTestWorkflow - hook token reuse after workflow completion (nextjs-webpack) · at 21:20:10Z · abandoned wrun_01M26K21SA5ZYBFQDDGYMG7MKV
  • run-pickup-stall · concurrent hook token conflict - two workflows cannot use the same hook token simultaneously (nextjs-webpack) · at 21:20:14Z · abandoned wrun_01M26K25T7PA8YPTGZJX7H7RSR

E2E Test Summary

Summary
Passed Failed Skipped Total
✅ ▲ Vercel Production 3662 0 685 4347
✅ 💻 Local Development 3922 0 586 4508
✅ 📦 Local Production 3922 0 586 4508
✅ 🐘 Local Postgres 3922 0 586 4508
✅ 🪟 Windows 320 0 2 322
✅ 🌐 Cross-language Conformance 68 0 74 142
✅ vercel-http-transport 823 0 143 966
✅ vercel-multi-region 27 0 0 27
✅ vercel-ws-transport 557 0 87 644
Total 17223 0 2749 19972
Details by Category

✅ ▲ Vercel Production

App Passed Failed Skipped
✅ astro-node 133 0 28
✅ astro-quickjs 133 0 28
✅ example-node 133 0 28
✅ example-quickjs 133 0 28
✅ express-node 133 0 28
✅ express-quickjs 133 0 28
✅ fastify-node 133 0 28
✅ fastify-quickjs 133 0 28
✅ hono-node 133 0 28
✅ hono-quickjs 133 0 28
✅ nest-node 133 0 28
✅ nest-quickjs 133 0 28
✅ nextjs-turbopack-node 158 0 3
✅ nextjs-turbopack-quickjs 158 0 3
✅ nextjs-webpack-node 158 0 3
✅ nextjs-webpack-quickjs 158 0 3
✅ nitro-node 133 0 28
✅ nitro-quickjs 133 0 28
✅ nuxt-node 133 0 28
✅ nuxt-quickjs 133 0 28
✅ python-node 66 0 95
✅ sveltekit-node 152 0 9
✅ sveltekit-quickjs 152 0 9
✅ tanstack-start-node 133 0 28
✅ tanstack-start-quickjs 133 0 28
✅ vite-node 133 0 28
✅ vite-quickjs 133 0 28

✅ 💻 Local Development

App Passed Failed Skipped
✅ astro-stable-node 134 0 27
✅ astro-stable-quickjs 134 0 27
✅ express-stable-node 134 0 27
✅ express-stable-quickjs 134 0 27
✅ fastify-stable-node 134 0 27
✅ fastify-stable-quickjs 134 0 27
✅ hono-stable-node 134 0 27
✅ hono-stable-quickjs 134 0 27
✅ nest-stable-node 134 0 27
✅ nest-stable-quickjs 134 0 27
✅ nextjs-turbopack-canary-node 141 0 20
✅ nextjs-turbopack-canary-quickjs 141 0 20
✅ nextjs-turbopack-stable-node 160 0 1
✅ nextjs-turbopack-stable-quickjs 160 0 1
✅ nextjs-webpack-canary-node 141 0 20
✅ nextjs-webpack-canary-quickjs 141 0 20
✅ nextjs-webpack-stable-node 160 0 1
✅ nextjs-webpack-stable-quickjs 160 0 1
✅ nitro-stable-node 134 0 27
✅ nitro-stable-quickjs 134 0 27
✅ nuxt-stable-node 134 0 27
✅ nuxt-stable-quickjs 134 0 27
✅ sveltekit-stable-node 153 0 8
✅ sveltekit-stable-quickjs 153 0 8
✅ tanstack-start-node 134 0 27
✅ tanstack-start-quickjs 134 0 27
✅ vite-stable-node 134 0 27
✅ vite-stable-quickjs 134 0 27

✅ 📦 Local Production

App Passed Failed Skipped
✅ astro-stable-node 134 0 27
✅ astro-stable-quickjs 134 0 27
✅ express-stable-node 134 0 27
✅ express-stable-quickjs 134 0 27
✅ fastify-stable-node 134 0 27
✅ fastify-stable-quickjs 134 0 27
✅ hono-stable-node 134 0 27
✅ hono-stable-quickjs 134 0 27
✅ nest-stable-node 134 0 27
✅ nest-stable-quickjs 134 0 27
✅ nextjs-turbopack-canary-node 141 0 20
✅ nextjs-turbopack-canary-quickjs 141 0 20
✅ nextjs-turbopack-stable-node 160 0 1
✅ nextjs-turbopack-stable-quickjs 160 0 1
✅ nextjs-webpack-canary-node 141 0 20
✅ nextjs-webpack-canary-quickjs 141 0 20
✅ nextjs-webpack-stable-node 160 0 1
✅ nextjs-webpack-stable-quickjs 160 0 1
✅ nitro-stable-node 134 0 27
✅ nitro-stable-quickjs 134 0 27
✅ nuxt-stable-node 134 0 27
✅ nuxt-stable-quickjs 134 0 27
✅ sveltekit-stable-node 153 0 8
✅ sveltekit-stable-quickjs 153 0 8
✅ tanstack-start-node 134 0 27
✅ tanstack-start-quickjs 134 0 27
✅ vite-stable-node 134 0 27
✅ vite-stable-quickjs 134 0 27

✅ 🐘 Local Postgres

App Passed Failed Skipped
✅ astro-stable-node 134 0 27
✅ astro-stable-quickjs 134 0 27
✅ express-stable-node 134 0 27
✅ express-stable-quickjs 134 0 27
✅ fastify-stable-node 134 0 27
✅ fastify-stable-quickjs 134 0 27
✅ hono-stable-node 134 0 27
✅ hono-stable-quickjs 134 0 27
✅ nest-stable-node 134 0 27
✅ nest-stable-quickjs 134 0 27
✅ nextjs-turbopack-canary-node 141 0 20
✅ nextjs-turbopack-canary-quickjs 141 0 20
✅ nextjs-turbopack-stable-node 160 0 1
✅ nextjs-turbopack-stable-quickjs 160 0 1
✅ nextjs-webpack-canary-node 141 0 20
✅ nextjs-webpack-canary-quickjs 141 0 20
✅ nextjs-webpack-stable-node 160 0 1
✅ nextjs-webpack-stable-quickjs 160 0 1
✅ nitro-stable-node 134 0 27
✅ nitro-stable-quickjs 134 0 27
✅ nuxt-stable-node 134 0 27
✅ nuxt-stable-quickjs 134 0 27
✅ sveltekit-stable-node 153 0 8
✅ sveltekit-stable-quickjs 153 0 8
✅ tanstack-start-node 134 0 27
✅ tanstack-start-quickjs 134 0 27
✅ vite-stable-node 134 0 27
✅ vite-stable-quickjs 134 0 27

✅ 🪟 Windows

App Passed Failed Skipped
✅ nextjs-turbopack-node 160 0 1
✅ nextjs-turbopack-quickjs 160 0 1

✅ 🌐 Cross-language Conformance

App Passed Failed Skipped
✅ python 68 0 74

✅ vercel-http-transport

App Passed Failed Skipped
✅ example 133 0 28
✅ express 133 0 28
✅ hono 133 0 28
✅ nextjs-turbopack 158 0 3
✅ nitro 133 0 28
✅ vite 133 0 28

✅ vercel-multi-region

App Passed Failed Skipped
✅ nextjs-turbopack 27 0 0

✅ vercel-ws-transport

App Passed Failed Skipped
✅ example 133 0 28
✅ express 133 0 28
✅ nextjs-turbopack 158 0 3
✅ vite 133 0 28

📋 View full workflow run

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📊 Workflow Benchmarks

commit c6f7d03 · Thu, 10 Sep 2026 21:33:50 GMT · run logs

Backend: vercel · app: nextjs-turbopack

Metric Scenario Best (ms) P75 (ms) P90 (ms) P99 (ms) Samples
TTFS step 187 (-71%) 💚 1343 🔴 (+29%) 🔻 1394 🔴 (+26%) 🔻 1797 🔴 (+19%) 🔻 30
TTFS stream 177 (+0.6%) 1265 🔴 (+23%) 🔻 1336 🔴 (+26%) 🔻 1380 🔴 (+25%) 🔻 30
TTFS hook + stream 422 (-3.9%) 1514 🔴 (+13%) 1553 🔴 (-1.1%) 6286 🔴 (+20%) 🔻 30
Fan-out TTFS Promise.all(100 steps) 638 (+12%) 1902 (+142%) 🔻 2031 (+149%) 🔻 2167 (+28%) 🔻 10
Fan-out TTLS Promise.all(100 steps) 2186 (+40%) 🔻 3679 (-5.6%) 5492 (+8.5%) 8105 (+11%) 10
STSO 1020 steps (inline) 112 (+5.7%) 141 (+4.4%) 161 (+10%) 236 (+7.3%) 1019
WO 1020 steps 142126 (+5.9%) 142126 (+5.9%) 142126 (+5.9%) 142126 (+5.9%) 1
CRTT first chunk (pooled) 68 (+19%) 🔻 93 (-8.8%) 100 (-26%) 💚 140 (-18%) 💚 28

Streams

Scenario CRTT 1st p75 p90 p99 CDV max iters
paced control (100/s, 60B) 81 (+5%) 167 (+25%) 323 (+42%) 499 (-1%) 152 (+50%) 10
size sweep (100/s, 160B-12KB) 84.5 (+10%) 174 (+18%) 217 (+7%) 341 (+6%) 161 (+36%) 10
replay gateway-gpt-5.4-nano-2000t (1x) 88 (-4%) 140 (-12%) 185 (-26%) 366 (-47%) 292 (-10%) 3
replay eve-gpt-5.6-sol-2000t (1x) 89 (-5%) 139 (+1%) 182 (-15%) 462 (-36%) 289 (-46%) 2
replay eve-gpt-5.6-sol-2000t (2x) 99 (-15%) 225 (-78%) 417 (-87%) 724 (-86%) 246 (-47%) 3
📈 STSO distribution vs main (inline / queue-hop histograms)

1020 steps (inline)

Cumulative STSO time: main 134043ms → this run 141697ms (Δ +7654ms, +6%)

100-150 ms  █████████████████████┃██  main 938  this 846   -92
150-200 ms  ██░┃                      main  69  this 148   +79
200-250 ms  ┃                         main   7  this  16    +9
250-300 ms  ┃                         main   3  this   6    +3
300-350 ms  ┃                         main   2  this   2    +0
350-400 ms  ┃                         main   0  this   1    +1
📈 CRTT drill-down vs main (RTT distributions & profiles)
variant  RTT 1ms→5s+             avg         p50         p90         p99     n
control  ······▃█▂▁···  138.3 (+13%)  123 (+11%)  323 (+42%)   499 (-1%)  3000
sweep    ······▂█▁····  138.9 (+20%)  128 (+21%)   217 (+7%)   341 (+6%)  3000
gw 1x    ·····▁▄█▁▁···   122.7 (-5%)   114 (+4%)  185 (-26%)  366 (-47%)  5295
eve 1x   ·····▁▅█▁▁···   124.6 (-6%)   111 (+3%)  182 (-15%)  462 (-36%)  5186
eve 2x   ·····▁▂█▄▁···  186.6 (-56%)   152 (+8%)  417 (-87%)  724 (-86%)  7779

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

control  ▃▃▃▄█▃▃▂▂▁  119–181ms
sweep    ▇█▄▃▂▁▃▆▇▂  123–158ms
gw 1x    ▅█▁▃▄█▃▁▃▆  107–141ms
eve 1x   ▃▃▄▃▁▃█▆▇█  106–142ms
eve 2x   ▁▁▂▁▂▅▄█▆▂  134–305ms

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

sweep  ▆▅▁▄█▅▇  138–140ms

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

control  ▅▃▅█▅▂▄▄▄▁  37–48ms
sweep    ▁▃▅▆▄▃▅█▅▃  47–71ms
gw 1x    ▆█▁▃▆█▆▁▄▆  29–42ms
eve 1x   ▃▅▅▃▃▃▇▁▆█  20–30ms
eve 2x   ▄▂▄▁▅█▂▄▁▄  23–37ms
📜 Previous results (1)

f2af506

Tue, 08 Sep 2026 20:49:37 GMT · run logs

vercel / nextjs-turbopack

Metric Scenario Best (ms) P75 (ms) P90 (ms) P99 (ms) Samples
TTFS step 179 (-81%) 💚 1263 🔴 (+27%) 🔻 1419 🔴 (+28%) 🔻 1785 🔴 (+33%) 🔻 30
TTFS stream 176 (-34%) 💚 1286 🔴 (+32%) 🔻 1309 🔴 (+29%) 🔻 1481 🔴 (+41%) 🔻 30
TTFS hook + stream 601 (+31%) 🔻 1554 🔴 (+24%) 🔻 1608 🔴 (+25%) 🔻 1699 🔴 (+28%) 🔻 30
Fan-out TTFS Promise.all(100 steps) 611 (+6.6%) 1894 (+26%) 🔻 1988 (+31%) 🔻 2035 (-55%) 💚 10
Fan-out TTLS Promise.all(100 steps) 1707 (±0%) 3729 (+22%) 🔻 3920 (+5.3%) 4481 (-54%) 💚 10
STSO 1020 steps (inline) 71 (-29%) 💚 164 (+40%) 🔻 223 (+63%) 🔻 342 (+83%) 🔻 1019
WO 1020 steps 152782 (+26%) 🔻 152782 (+26%) 🔻 152782 (+26%) 🔻 152782 (+26%) 🔻 1
CRTT first chunk (pooled) 54 (+15%) 89 (+2.3%) 145 (+38%) 🔻 176 (-41%) 💚 28

Streams

Scenario CRTT 1st p75 p90 p99 CDV max iters
paced control (100/s, 60B) 78 (+23%) 147 (+34%) 253 (+53%) 501 (+48%) 94 (-17%) 10
size sweep (100/s, 160B-12KB) 71 (+4%) 159 (+42%) 198 (+13%) 268 (-42%) 128 (+23%) 10
replay gateway-gpt-5.4-nano-2000t (1x) 83 (-61%) 136 (+12%) 195 (+15%) 361 (-24%) 181 (+12%) 3
replay eve-gpt-5.6-sol-2000t (1x) 88.5 (+13%) 127 (+14%) 157 (+11%) 313 (-20%) 254 (-24%) 2
replay eve-gpt-5.6-sol-2000t (2x) 94 (+38%) 180 (-4%) 269 (+8%) 672 (+73%) 321 (+61%) 3
ℹ️ Metric definitions & methodology

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

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.

… page

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
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Sim World

Simulated world deterministic testing for races. Traces

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

fence=per-spec

scenario outcome events virt replay 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 completed 17 1.0m ok 0
❌ in-flight-before-decision-counted completed 17 1.0m ok 0
✅ in-flight-after-decision completed 19 2.0m ok 0
✅ 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.txt

? (eventLog.cursor ?? undefined)
: eventLog.type === 'loadAfter'
? eventLog.cursor
: undefined,

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nit: the nesting here is getting insane, im not sure how much this stuff matters in the current era of software dev but seems like we might be due for refactor

@VaguelySerious
VaguelySerious merged commit ec57aff into main Sep 10, 2026
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@VaguelySerious
VaguelySerious deleted the peter/divergence-diagnostics branch September 10, 2026 22:16
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No backport to stable for ec57aff (AI decision).

This is a diagnostics enhancement, not a fix: it adds new observability surface (a new replay-divergence.ts module, EventsConsumer.describe(), a dozen new log fields, and a new optional eventIds field on the queue payload schema) and explicitly states "No behavior change", so no correctness, crash, or data-loss defect on stable is addressed. The one genuine defect it repairs — composeLogLine listing errorMessage as well-known but never rendering it — lives in packages/core/src/log-format.ts, which does not exist on origin/stable (nor does the touched docs/content/docs/v5/errors/corrupted-event-log.mdx), so that part is main-only. If richer divergence diagnostics are wanted on the maintenance line, force it through via workflow_dispatch after adapting it to stable's logger.

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

ec57aff3be53c7404191de41b7a140d814235efa

pranaygp added a commit that referenced this pull request Sep 10, 2026
…ry-2

* origin/main:
  [core] Log pending consumers in divergence diagnostics (#4021)
  fix(web-shared): stop event payload stub flash in events view (#3951)
  fix: order the 429 check before the 4xx check in the workflow skill (#3915)
  test(swc-plugin): verify class-name preservation at runtime (#4015)
  (chore) Update Next.js to 16.3.4 in the workbench apps and @workflow/next (#4026)
pranaygp added a commit that referenced this pull request Sep 13, 2026
`runtime.ts` computes a source-map-remapped `errorStack` when a run fails and
passes it to a log whose framing line — "Error while running workflow" — has
no body of its own. `composeLogLine` drops `errorStack` unconditionally, on
the assumption (true for the step executor and the combined runtime, which
render `${framing}\n${stack}`, false here) that the message already carries
it. The stack never reaches the console; #4021 noted this at the call site
and worked around it by adding `errorMessage`, but the stack itself is still
discarded.

- `composeLogLine` promotes the `errorStack` field into the stack body when
  the message carries no body of its own, so it goes through the same frame
  trimming and is still never duplicated when the caller did embed one. This
  also lets #4021's existing `body.includes(errorMessage)` check suppress the
  now-redundant `error` row at this call site.
- The header row is skipped when it would be a lone class name that the
  promoted stack header already states. A badge still always renders —
  attribution is the one thing the stack cannot express — so the step
  executor and combined-runtime sites are untouched, as is a stack naming a
  different class than `errorName`.

Adds a runtime-level regression test that drives a throwing workflow through
`workflowEntrypoint` and asserts the emitted `console.error` line carries the
message and a stack frame, plus formatter unit tests for the promote,
don't-duplicate, badge and different-class cases. No existing snapshot
changes: the composition is identical everywhere except the run-failure log.

Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>

Co-Authored-By: Pranay Prakash <1797812+pranaygp@users.noreply.github.com>
pranaygp added a commit that referenced this pull request Sep 13, 2026
`runtime.ts` computes a source-map-remapped `errorStack` when a run fails and
passes it to a log whose framing line — "Error while running workflow" — has
no body of its own. `composeLogLine` drops `errorStack` unconditionally, on
the assumption (true for the step executor and the combined runtime, which
render `${framing}\n${stack}`, false here) that the message already carries
it. The stack never reaches the console; #4021 noted this at the call site
and worked around it by adding `errorMessage`, but the stack itself is still
discarded.

- `composeLogLine` promotes the `errorStack` field into the stack body when
  the message carries no body of its own, so it goes through the same frame
  trimming and is still never duplicated when the caller did embed one. This
  also lets #4021's existing `body.includes(errorMessage)` check suppress the
  now-redundant `error` row at this call site.
- The header row is skipped when it would be a lone class name that the
  promoted stack header already states. A badge still always renders —
  attribution is the one thing the stack cannot express — so the step
  executor and combined-runtime sites are untouched, as is a stack naming a
  different class than `errorName`.

Adds a runtime-level regression test that drives a throwing workflow through
`workflowEntrypoint` and asserts the emitted `console.error` line carries the
message and a stack frame, plus formatter unit tests for the promote,
don't-duplicate, badge and different-class cases. No existing snapshot
changes: the composition is identical everywhere except the run-failure log.

Co-authored-by: vercel[bot] <35613825+vercel[bot]@users.noreply.github.com>
Co-authored-by: Pranay Prakash <1797812+pranaygp@users.noreply.github.com>

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