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🧪 E2E Test Results

Some tests failed

❌ Failed E2E Tests

📦 Local Production (1 failed)

nextjs-turbopack-stable (1 failed):

  • webhookWorkflow | wrun_41KYTDX1350GG8DR5EPJ6MMEPN

E2E Test Summary

Summary
PassedFailedSkippedTotal
✅ ▲ Vercel Production145502391694
✅ 💻 Local Development148602081694
❌ 📦 Local Production162012271848
✅ 🐘 Local Postgres162102271848
✅ 📋 Other102002121232
✅ vercel-multi-region270027
Total7229111138343
Details by Category

✅ ▲ Vercel Production

AppPassedFailedSkipped
✅ astro126028
✅ example126028
✅ express126028
✅ fastify126028
✅ hono126028
✅ nextjs-turbopack15103
✅ nextjs-webpack15103
✅ nitro126028
✅ nuxt126028
✅ sveltekit14509
✅ vite126028

✅ 💻 Local Development

AppPassedFailedSkipped
✅ astro-stable128026
✅ express-stable128026
✅ fastify-stable128026
✅ hono-stable128026
✅ nextjs-turbopack-canary135019
✅ nextjs-turbopack-stable15400
✅ nextjs-webpack-stable15400
✅ nitro-stable128026
✅ nuxt-stable128026
✅ sveltekit-stable14707
✅ vite-stable128026

❌ 📦 Local Production

AppPassedFailedSkipped
✅ astro-stable128026
✅ express-stable128026
✅ fastify-stable128026
✅ hono-stable128026
✅ nextjs-turbopack-canary135019
❌ nextjs-turbopack-stable15310
✅ nextjs-webpack-canary135019
✅ nextjs-webpack-stable15400
✅ nitro-stable128026
✅ nuxt-stable128026
✅ sveltekit-stable14707
✅ vite-stable128026

✅ 🐘 Local Postgres

AppPassedFailedSkipped
✅ astro-stable128026
✅ express-stable128026
✅ fastify-stable128026
✅ hono-stable128026
✅ nextjs-turbopack-canary135019
✅ nextjs-turbopack-stable15400
✅ nextjs-webpack-canary135019
✅ nextjs-webpack-stable15400
✅ nitro-stable128026
✅ nuxt-stable128026
✅ sveltekit-stable14707
✅ vite-stable128026

✅ 📋 Other

AppPassedFailedSkipped
✅ e2e-local-dev-nest-stable128026
✅ e2e-local-dev-tanstack-start-128026
✅ e2e-local-postgres-nest-stable128026
✅ e2e-local-postgres-tanstack-start-128026
✅ e2e-local-prod-nest-stable128026
✅ e2e-local-prod-tanstack-start-128026
✅ e2e-vercel-prod-nest126028
✅ e2e-vercel-prod-tanstack-start126028

✅ vercel-multi-region

AppPassedFailedSkipped
✅ nextjs-turbopack2700

📋 View full workflow run

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📊 Workflow Benchmarks

commit 32225d9 · Thu, 30 Jul 2026 21:31:15 GMT · run logs

Backend: vercel · app: nextjs-turbopack

MetricScenarioBest (ms)P75 (ms)P90 (ms)P99 (ms)Samples
TTFSstep1308 (+523%) 🔻1358 🔴 (+28%) 🔻1382 🔴 (+27%) 🔻1525 🔴 (+25%) 🔻30
TTFSstream1319 (+390%) 🔻1368 🔴 (+27%) 🔻1396 🔴 (+27%) 🔻1538 🔴 (+31%) 🔻30
TTFShook + stream1506 (+298%) 🔻1607 🔴 (+28%) 🔻1655 🔴 (+28%) 🔻1788 🔴 (+14%)30
STSO1020 steps (inline)162 (-9.0%)476 (-1.0%)531 (-0.7%)790 (+15%) 🔻1016
STSO1020 steps (queue-hop)2160 (+33%) 🔻3168 (+5.8%)3168 (+5.8%)3168 (+5.8%)3
WO1020 steps402163 (-3.4%)402163 (-3.4%)402163 (-3.4%)402163 (-3.4%)1
SLstream latency72 (-11%)160 🔴 (+8.8%)194 🔴 (+6.0%)229 🔴 (-36%) 💚30
SOstream overhead (text)97 (-22%) 💚145 (-34%) 💚162 (-35%) 💚186 (-57%) 💚30
SOstream overhead (structured)94 (-19%) 💚143 (-38%) 💚161 (-47%) 💚203 (-45%) 💚30
📈 STSO distribution vs main (inline / queue-hop histograms)

1020 steps (inline)

Cumulative STSO time: main 408200ms → this run 392365ms (Δ -15835ms, -4%)

 150-200 ms █░░░░┃ main 11 this 48 +37
200-250 ms █████████┃█ main 81 this 75 -6
250-300 ms ████████████████┃█ main 142 this 134 -8
300-350 ms ███████████████░░░░░░░░┃ main 112 this 185 +73
350-400 ms ██████████████████░░░░┃ main 136 this 175 +39
400-450 ms ████████████┃██████████ main 181 this 99 -82
450-500 ms ███████████████┃████ main 153 this 127 -26
500-550 ms ████████████┃██ main 119 this 101 -18
550-600 ms ██┃███ main 44 this 25 -19
600-650 ms ██┃ main 19 this 20 +1
650-700 ms ┃ main 9 this 4 -5
700-750 ms ┃ main 3 this 9 +6
750-800 ms ┃ main 2 this 4 +2
800-850 ms ┃ main 0 this 3 +3
850-900 ms ┃ main 3 this 0 -3
900-950 ms ┃ main 0 this 1 +1
950-1000 ms ┃ main 0 this 1 +1
1000-1050 ms ┃ main 1 this 2 +1
1050-1100 ms ┃ main 0 this 1 +1
1200-1250 ms ┃ main 0 this 1 +1
1300-1350 ms ┃ main 0 this 1 +1

1020 steps (queue-hop)

Cumulative STSO time: main 7007ms → this run 8436ms (Δ +1429ms, +20%)

1500-2000 ms ┃███████████ main 1 this 0 -1
2000-2500 ms ███████████┃ main 1 this 1 +0
2500-3000 ms ┃███████████ main 1 this 0 -1
3000-3500 ms ░░░░░░░░░░░░░░░░░░░░░░░┃ main 0 this 2 +2
📜 Previous results (1)

a4339dc

Fri, 24 Jul 2026 22:12:45 GMT · run logs

vercel / nextjs-turbopack

MetricScenarioBest (ms)P75 (ms)P90 (ms)P99 (ms)Samples
TTFSstep1061 (+37%) 🔻1387 🔴 (+27%) 🔻1400 🔴 (+25%) 🔻1522 🔴 (-2.7%)30
TTFSstream1260 (+524%) 🔻1383 🔴 (+32%) 🔻1406 🔴 (+31%) 🔻1443 🔴 (+29%) 🔻30
TTFShook + stream635 (-48%) 💚1599 🔴 (+20%) 🔻1679 🔴 (+12%)1979 🔴 (+1.3%)30
STSO1020 steps (1-20)161 (-2.4%)271 🔴 (+2.7%)383 🔴 (-3.0%)415 🔴 (-17%) 💚19
STSO1020 steps (101-120)186 (+13%)244 🔴 (-2.4%)367 🔴 (+4.3%)369 🔴 (+4.5%)19
STSO1020 steps (1001-1020)483 (+1.0%)574 🔴 (+6.3%)648 🔴 (+13%)700 🔴 (+21%) 🔻19
WO1020 steps380712 (-0.9%)380712 (-0.9%)380712 (-0.9%)380712 (-0.9%)1
SLstream latency87 (+16%) 🔻160 🔴 (+31%) 🔻176 🔴 (+39%) 🔻796 🔴 (-1.6%)30
SOstream overhead (text)108 (+17%) 🔻187 (+22%) 🔻251 (+43%) 🔻297 (-17%) 💚30
SOstream overhead (structured)95 (-7.8%)146 (-7.0%)182 (+1.1%)338 (+50%) 🔻30
ℹ️ Metric definitions & methodology

The collapsed STSO distribution section above buckets every step gap of the sequential-steps run (not a sampled window), split by whether the step ending the gap ran inline — in the same warm process as the step before it, so the gap is pure framework overhead — or after a queue-hop — the first step of a fresh process, which pays queue dispatch, client reinit and event-log replay. Bars overlay the two runs: is main, marks where this run lands, bridges the gap when this run has more samples in a bucket.

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, deployment clocks) · STSO: step-to-step overhead (gap between consecutive step bodies) · WO: workflow overhead (whole-run time outside step bodies, in-deployment anchored) · SL: stream latency (in-deployment write → read propagation, readAt - writtenAt) · SO: stream overhead (end-to-end write+consume time beyond the modelled generation window)

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 · stream latency: parallel reader/writer steps on a dedicated stream; SL is the in-deployment write->read propagation (readAt - writtenAt) · stream overhead (text): writer streams 300 variable-length text token deltas paced at 100/s for 3s (a haiku-size LLM's token throughput) while a parallel reader drains the whole stream; SO is the end-to-end write+consume time beyond the 3s generation window (overhead/backpressure) · stream overhead (structured): same workload as stream overhead (text), but each delta is an AI-SDK-style structured object ({ type: 'text-delta', id, text }) instead of a raw string, so the SO gap vs the text scenario is the added serialization cost

🔴 marks a percentile over its target (within target is left unmarked). Targets (p75/p90/p99, ms) — TTFS 200/300/600 · SL 50/60/125 · SO 250/500/1000

All metrics are measured from deployment-side timestamps only. Runs are triggered by an in-deployment route that stamps the anchor (clientStart) right before start(), so the CI runner’s request and its path through api.vercel.com sit outside every measured window. TTFS = in-deployment start() → first step body (turbo uses the in-process fast path, non-turbo the dispatch path), and includes the VQS dispatch hop plus any /flow cold start. STSO/WO are measured between step bodies on the deployment. SL is measured inside the workflow (parallel reader/writer steps), so it no longer includes the api.vercel.com read path.

Cold starts are kept in the numbers on purpose — they are part of real bursty-workload latency. The workbench deployment cold-starts the /flow invocation for a large fraction of runs, inflating P75+; the Best column shows the fastest (warm-start) sample for comparison.

Co-Authored-By: shalabhc <shalabh.chaturvedi@vercel.com>
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no-op to test benchmark variance by shalabhc · Pull Request #3101 · vercel/workflow · GitHub
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no-op to test benchmark variance - #3101

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⚠️ No Changeset found

Latest commit: 32225d9

Merging this PR will not cause a version bump for any packages. If these changes should not result in a new version, you're good to go. If these changes should result in a version bump, you need to add a changeset.

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🧪 E2E Test Results

Some tests failed

❌ Failed E2E Tests

📦 Local Production (1 failed)

nextjs-turbopack-stable (1 failed):

  • webhookWorkflow | wrun_41KYTDX1350GG8DR5EPJ6MMEPN

E2E Test Summary

Summary
PassedFailedSkippedTotal
✅ ▲ Vercel Production145502391694
✅ 💻 Local Development148602081694
❌ 📦 Local Production162012271848
✅ 🐘 Local Postgres162102271848
✅ 📋 Other102002121232
✅ vercel-multi-region270027
Total7229111138343
Details by Category

✅ ▲ Vercel Production

AppPassedFailedSkipped
✅ astro126028
✅ example126028
✅ express126028
✅ fastify126028
✅ hono126028
✅ nextjs-turbopack15103
✅ nextjs-webpack15103
✅ nitro126028
✅ nuxt126028
✅ sveltekit14509
✅ vite126028

✅ 💻 Local Development

AppPassedFailedSkipped
✅ astro-stable128026
✅ express-stable128026
✅ fastify-stable128026
✅ hono-stable128026
✅ nextjs-turbopack-canary135019
✅ nextjs-turbopack-stable15400
✅ nextjs-webpack-stable15400
✅ nitro-stable128026
✅ nuxt-stable128026
✅ sveltekit-stable14707
✅ vite-stable128026

❌ 📦 Local Production

AppPassedFailedSkipped
✅ astro-stable128026
✅ express-stable128026
✅ fastify-stable128026
✅ hono-stable128026
✅ nextjs-turbopack-canary135019
❌ nextjs-turbopack-stable15310
✅ nextjs-webpack-canary135019
✅ nextjs-webpack-stable15400
✅ nitro-stable128026
✅ nuxt-stable128026
✅ sveltekit-stable14707
✅ vite-stable128026

✅ 🐘 Local Postgres

AppPassedFailedSkipped
✅ astro-stable128026
✅ express-stable128026
✅ fastify-stable128026
✅ hono-stable128026
✅ nextjs-turbopack-canary135019
✅ nextjs-turbopack-stable15400
✅ nextjs-webpack-canary135019
✅ nextjs-webpack-stable15400
✅ nitro-stable128026
✅ nuxt-stable128026
✅ sveltekit-stable14707
✅ vite-stable128026

✅ 📋 Other

AppPassedFailedSkipped
✅ e2e-local-dev-nest-stable128026
✅ e2e-local-dev-tanstack-start-128026
✅ e2e-local-postgres-nest-stable128026
✅ e2e-local-postgres-tanstack-start-128026
✅ e2e-local-prod-nest-stable128026
✅ e2e-local-prod-tanstack-start-128026
✅ e2e-vercel-prod-nest126028
✅ e2e-vercel-prod-tanstack-start126028

✅ vercel-multi-region

AppPassedFailedSkipped
✅ nextjs-turbopack2700

📋 View full workflow run

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📊 Workflow Benchmarks

commit 32225d9 · Thu, 30 Jul 2026 21:31:15 GMT · run logs

Backend: vercel · app: nextjs-turbopack

MetricScenarioBest (ms)P75 (ms)P90 (ms)P99 (ms)Samples
TTFSstep1308 (+523%) 🔻1358 🔴 (+28%) 🔻1382 🔴 (+27%) 🔻1525 🔴 (+25%) 🔻30
TTFSstream1319 (+390%) 🔻1368 🔴 (+27%) 🔻1396 🔴 (+27%) 🔻1538 🔴 (+31%) 🔻30
TTFShook + stream1506 (+298%) 🔻1607 🔴 (+28%) 🔻1655 🔴 (+28%) 🔻1788 🔴 (+14%)30
STSO1020 steps (inline)162 (-9.0%)476 (-1.0%)531 (-0.7%)790 (+15%) 🔻1016
STSO1020 steps (queue-hop)2160 (+33%) 🔻3168 (+5.8%)3168 (+5.8%)3168 (+5.8%)3
WO1020 steps402163 (-3.4%)402163 (-3.4%)402163 (-3.4%)402163 (-3.4%)1
SLstream latency72 (-11%)160 🔴 (+8.8%)194 🔴 (+6.0%)229 🔴 (-36%) 💚30
SOstream overhead (text)97 (-22%) 💚145 (-34%) 💚162 (-35%) 💚186 (-57%) 💚30
SOstream overhead (structured)94 (-19%) 💚143 (-38%) 💚161 (-47%) 💚203 (-45%) 💚30
📈 STSO distribution vs main (inline / queue-hop histograms)

1020 steps (inline)

Cumulative STSO time: main 408200ms → this run 392365ms (Δ -15835ms, -4%)

 150-200 ms █░░░░┃ main 11 this 48 +37
200-250 ms █████████┃█ main 81 this 75 -6
250-300 ms ████████████████┃█ main 142 this 134 -8
300-350 ms ███████████████░░░░░░░░┃ main 112 this 185 +73
350-400 ms ██████████████████░░░░┃ main 136 this 175 +39
400-450 ms ████████████┃██████████ main 181 this 99 -82
450-500 ms ███████████████┃████ main 153 this 127 -26
500-550 ms ████████████┃██ main 119 this 101 -18
550-600 ms ██┃███ main 44 this 25 -19
600-650 ms ██┃ main 19 this 20 +1
650-700 ms ┃ main 9 this 4 -5
700-750 ms ┃ main 3 this 9 +6
750-800 ms ┃ main 2 this 4 +2
800-850 ms ┃ main 0 this 3 +3
850-900 ms ┃ main 3 this 0 -3
900-950 ms ┃ main 0 this 1 +1
950-1000 ms ┃ main 0 this 1 +1
1000-1050 ms ┃ main 1 this 2 +1
1050-1100 ms ┃ main 0 this 1 +1
1200-1250 ms ┃ main 0 this 1 +1
1300-1350 ms ┃ main 0 this 1 +1

1020 steps (queue-hop)

Cumulative STSO time: main 7007ms → this run 8436ms (Δ +1429ms, +20%)

1500-2000 ms ┃███████████ main 1 this 0 -1
2000-2500 ms ███████████┃ main 1 this 1 +0
2500-3000 ms ┃███████████ main 1 this 0 -1
3000-3500 ms ░░░░░░░░░░░░░░░░░░░░░░░┃ main 0 this 2 +2
📜 Previous results (1)

a4339dc

Fri, 24 Jul 2026 22:12:45 GMT · run logs

vercel / nextjs-turbopack

MetricScenarioBest (ms)P75 (ms)P90 (ms)P99 (ms)Samples
TTFSstep1061 (+37%) 🔻1387 🔴 (+27%) 🔻1400 🔴 (+25%) 🔻1522 🔴 (-2.7%)30
TTFSstream1260 (+524%) 🔻1383 🔴 (+32%) 🔻1406 🔴 (+31%) 🔻1443 🔴 (+29%) 🔻30
TTFShook + stream635 (-48%) 💚1599 🔴 (+20%) 🔻1679 🔴 (+12%)1979 🔴 (+1.3%)30
STSO1020 steps (1-20)161 (-2.4%)271 🔴 (+2.7%)383 🔴 (-3.0%)415 🔴 (-17%) 💚19
STSO1020 steps (101-120)186 (+13%)244 🔴 (-2.4%)367 🔴 (+4.3%)369 🔴 (+4.5%)19
STSO1020 steps (1001-1020)483 (+1.0%)574 🔴 (+6.3%)648 🔴 (+13%)700 🔴 (+21%) 🔻19
WO1020 steps380712 (-0.9%)380712 (-0.9%)380712 (-0.9%)380712 (-0.9%)1
SLstream latency87 (+16%) 🔻160 🔴 (+31%) 🔻176 🔴 (+39%) 🔻796 🔴 (-1.6%)30
SOstream overhead (text)108 (+17%) 🔻187 (+22%) 🔻251 (+43%) 🔻297 (-17%) 💚30
SOstream overhead (structured)95 (-7.8%)146 (-7.0%)182 (+1.1%)338 (+50%) 🔻30
ℹ️ Metric definitions & methodology

The collapsed STSO distribution section above buckets every step gap of the sequential-steps run (not a sampled window), split by whether the step ending the gap ran inline — in the same warm process as the step before it, so the gap is pure framework overhead — or after a queue-hop — the first step of a fresh process, which pays queue dispatch, client reinit and event-log replay. Bars overlay the two runs: is main, marks where this run lands, bridges the gap when this run has more samples in a bucket.

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, deployment clocks) · STSO: step-to-step overhead (gap between consecutive step bodies) · WO: workflow overhead (whole-run time outside step bodies, in-deployment anchored) · SL: stream latency (in-deployment write → read propagation, readAt - writtenAt) · SO: stream overhead (end-to-end write+consume time beyond the modelled generation window)

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 · stream latency: parallel reader/writer steps on a dedicated stream; SL is the in-deployment write->read propagation (readAt - writtenAt) · stream overhead (text): writer streams 300 variable-length text token deltas paced at 100/s for 3s (a haiku-size LLM's token throughput) while a parallel reader drains the whole stream; SO is the end-to-end write+consume time beyond the 3s generation window (overhead/backpressure) · stream overhead (structured): same workload as stream overhead (text), but each delta is an AI-SDK-style structured object ({ type: 'text-delta', id, text }) instead of a raw string, so the SO gap vs the text scenario is the added serialization cost

🔴 marks a percentile over its target (within target is left unmarked). Targets (p75/p90/p99, ms) — TTFS 200/300/600 · SL 50/60/125 · SO 250/500/1000

All metrics are measured from deployment-side timestamps only. Runs are triggered by an in-deployment route that stamps the anchor (clientStart) right before start(), so the CI runner’s request and its path through api.vercel.com sit outside every measured window. TTFS = in-deployment start() → first step body (turbo uses the in-process fast path, non-turbo the dispatch path), and includes the VQS dispatch hop plus any /flow cold start. STSO/WO are measured between step bodies on the deployment. SL is measured inside the workflow (parallel reader/writer steps), so it no longer includes the api.vercel.com read path.

Cold starts are kept in the numbers on purpose — they are part of real bursty-workload latency. The workbench deployment cold-starts the /flow invocation for a large fraction of runs, inflating P75+; the Best column shows the fastest (warm-start) sample for comparison.

Co-Authored-By: shalabhc <shalabh.chaturvedi@vercel.com>
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🧪 E2E Test Results

Some tests failed

❌ Failed E2E Tests

📦 Local Production (1 failed)

nextjs-turbopack-stable (1 failed):

  • webhookWorkflow | wrun_41KYTDX1350GG8DR5EPJ6MMEPN

E2E Test Summary

Summary
PassedFailedSkippedTotal
✅ ▲ Vercel Production145502391694
✅ 💻 Local Development148602081694
❌ 📦 Local Production162012271848
✅ 🐘 Local Postgres162102271848
✅ 📋 Other102002121232
✅ vercel-multi-region270027
Total7229111138343
Details by Category

✅ ▲ Vercel Production

AppPassedFailedSkipped
✅ astro126028
✅ example126028
✅ express126028
✅ fastify126028
✅ hono126028
✅ nextjs-turbopack15103
✅ nextjs-webpack15103
✅ nitro126028
✅ nuxt126028
✅ sveltekit14509
✅ vite126028

✅ 💻 Local Development

AppPassedFailedSkipped
✅ astro-stable128026
✅ express-stable128026
✅ fastify-stable128026
✅ hono-stable128026
✅ nextjs-turbopack-canary135019
✅ nextjs-turbopack-stable15400
✅ nextjs-webpack-stable15400
✅ nitro-stable128026
✅ nuxt-stable128026
✅ sveltekit-stable14707
✅ vite-stable128026

❌ 📦 Local Production

AppPassedFailedSkipped
✅ astro-stable128026
✅ express-stable128026
✅ fastify-stable128026
✅ hono-stable128026
✅ nextjs-turbopack-canary135019
❌ nextjs-turbopack-stable15310
✅ nextjs-webpack-canary135019
✅ nextjs-webpack-stable15400
✅ nitro-stable128026
✅ nuxt-stable128026
✅ sveltekit-stable14707
✅ vite-stable128026

✅ 🐘 Local Postgres

AppPassedFailedSkipped
✅ astro-stable128026
✅ express-stable128026
✅ fastify-stable128026
✅ hono-stable128026
✅ nextjs-turbopack-canary135019
✅ nextjs-turbopack-stable15400
✅ nextjs-webpack-canary135019
✅ nextjs-webpack-stable15400
✅ nitro-stable128026
✅ nuxt-stable128026
✅ sveltekit-stable14707
✅ vite-stable128026

✅ 📋 Other

AppPassedFailedSkipped
✅ e2e-local-dev-nest-stable128026
✅ e2e-local-dev-tanstack-start-128026
✅ e2e-local-postgres-nest-stable128026
✅ e2e-local-postgres-tanstack-start-128026
✅ e2e-local-prod-nest-stable128026
✅ e2e-local-prod-tanstack-start-128026
✅ e2e-vercel-prod-nest126028
✅ e2e-vercel-prod-tanstack-start126028

✅ vercel-multi-region

AppPassedFailedSkipped
✅ nextjs-turbopack2700

📋 View full workflow run

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📊 Workflow Benchmarks

commit 32225d9 · Thu, 30 Jul 2026 21:31:15 GMT · run logs

Backend: vercel · app: nextjs-turbopack

MetricScenarioBest (ms)P75 (ms)P90 (ms)P99 (ms)Samples
TTFSstep1308 (+523%) 🔻1358 🔴 (+28%) 🔻1382 🔴 (+27%) 🔻1525 🔴 (+25%) 🔻30
TTFSstream1319 (+390%) 🔻1368 🔴 (+27%) 🔻1396 🔴 (+27%) 🔻1538 🔴 (+31%) 🔻30
TTFShook + stream1506 (+298%) 🔻1607 🔴 (+28%) 🔻1655 🔴 (+28%) 🔻1788 🔴 (+14%)30
STSO1020 steps (inline)162 (-9.0%)476 (-1.0%)531 (-0.7%)790 (+15%) 🔻1016
STSO1020 steps (queue-hop)2160 (+33%) 🔻3168 (+5.8%)3168 (+5.8%)3168 (+5.8%)3
WO1020 steps402163 (-3.4%)402163 (-3.4%)402163 (-3.4%)402163 (-3.4%)1
SLstream latency72 (-11%)160 🔴 (+8.8%)194 🔴 (+6.0%)229 🔴 (-36%) 💚30
SOstream overhead (text)97 (-22%) 💚145 (-34%) 💚162 (-35%) 💚186 (-57%) 💚30
SOstream overhead (structured)94 (-19%) 💚143 (-38%) 💚161 (-47%) 💚203 (-45%) 💚30
📈 STSO distribution vs main (inline / queue-hop histograms)

1020 steps (inline)

Cumulative STSO time: main 408200ms → this run 392365ms (Δ -15835ms, -4%)

 150-200 ms █░░░░┃ main 11 this 48 +37
200-250 ms █████████┃█ main 81 this 75 -6
250-300 ms ████████████████┃█ main 142 this 134 -8
300-350 ms ███████████████░░░░░░░░┃ main 112 this 185 +73
350-400 ms ██████████████████░░░░┃ main 136 this 175 +39
400-450 ms ████████████┃██████████ main 181 this 99 -82
450-500 ms ███████████████┃████ main 153 this 127 -26
500-550 ms ████████████┃██ main 119 this 101 -18
550-600 ms ██┃███ main 44 this 25 -19
600-650 ms ██┃ main 19 this 20 +1
650-700 ms ┃ main 9 this 4 -5
700-750 ms ┃ main 3 this 9 +6
750-800 ms ┃ main 2 this 4 +2
800-850 ms ┃ main 0 this 3 +3
850-900 ms ┃ main 3 this 0 -3
900-950 ms ┃ main 0 this 1 +1
950-1000 ms ┃ main 0 this 1 +1
1000-1050 ms ┃ main 1 this 2 +1
1050-1100 ms ┃ main 0 this 1 +1
1200-1250 ms ┃ main 0 this 1 +1
1300-1350 ms ┃ main 0 this 1 +1

1020 steps (queue-hop)

Cumulative STSO time: main 7007ms → this run 8436ms (Δ +1429ms, +20%)

1500-2000 ms ┃███████████ main 1 this 0 -1
2000-2500 ms ███████████┃ main 1 this 1 +0
2500-3000 ms ┃███████████ main 1 this 0 -1
3000-3500 ms ░░░░░░░░░░░░░░░░░░░░░░░┃ main 0 this 2 +2
📜 Previous results (1)

a4339dc

Fri, 24 Jul 2026 22:12:45 GMT · run logs

vercel / nextjs-turbopack

MetricScenarioBest (ms)P75 (ms)P90 (ms)P99 (ms)Samples
TTFSstep1061 (+37%) 🔻1387 🔴 (+27%) 🔻1400 🔴 (+25%) 🔻1522 🔴 (-2.7%)30
TTFSstream1260 (+524%) 🔻1383 🔴 (+32%) 🔻1406 🔴 (+31%) 🔻1443 🔴 (+29%) 🔻30
TTFShook + stream635 (-48%) 💚1599 🔴 (+20%) 🔻1679 🔴 (+12%)1979 🔴 (+1.3%)30
STSO1020 steps (1-20)161 (-2.4%)271 🔴 (+2.7%)383 🔴 (-3.0%)415 🔴 (-17%) 💚19
STSO1020 steps (101-120)186 (+13%)244 🔴 (-2.4%)367 🔴 (+4.3%)369 🔴 (+4.5%)19
STSO1020 steps (1001-1020)483 (+1.0%)574 🔴 (+6.3%)648 🔴 (+13%)700 🔴 (+21%) 🔻19
WO1020 steps380712 (-0.9%)380712 (-0.9%)380712 (-0.9%)380712 (-0.9%)1
SLstream latency87 (+16%) 🔻160 🔴 (+31%) 🔻176 🔴 (+39%) 🔻796 🔴 (-1.6%)30
SOstream overhead (text)108 (+17%) 🔻187 (+22%) 🔻251 (+43%) 🔻297 (-17%) 💚30
SOstream overhead (structured)95 (-7.8%)146 (-7.0%)182 (+1.1%)338 (+50%) 🔻30
ℹ️ Metric definitions & methodology

The collapsed STSO distribution section above buckets every step gap of the sequential-steps run (not a sampled window), split by whether the step ending the gap ran inline — in the same warm process as the step before it, so the gap is pure framework overhead — or after a queue-hop — the first step of a fresh process, which pays queue dispatch, client reinit and event-log replay. Bars overlay the two runs: is main, marks where this run lands, bridges the gap when this run has more samples in a bucket.

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, deployment clocks) · STSO: step-to-step overhead (gap between consecutive step bodies) · WO: workflow overhead (whole-run time outside step bodies, in-deployment anchored) · SL: stream latency (in-deployment write → read propagation, readAt - writtenAt) · SO: stream overhead (end-to-end write+consume time beyond the modelled generation window)

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 · stream latency: parallel reader/writer steps on a dedicated stream; SL is the in-deployment write->read propagation (readAt - writtenAt) · stream overhead (text): writer streams 300 variable-length text token deltas paced at 100/s for 3s (a haiku-size LLM's token throughput) while a parallel reader drains the whole stream; SO is the end-to-end write+consume time beyond the 3s generation window (overhead/backpressure) · stream overhead (structured): same workload as stream overhead (text), but each delta is an AI-SDK-style structured object ({ type: 'text-delta', id, text }) instead of a raw string, so the SO gap vs the text scenario is the added serialization cost

🔴 marks a percentile over its target (within target is left unmarked). Targets (p75/p90/p99, ms) — TTFS 200/300/600 · SL 50/60/125 · SO 250/500/1000

All metrics are measured from deployment-side timestamps only. Runs are triggered by an in-deployment route that stamps the anchor (clientStart) right before start(), so the CI runner’s request and its path through api.vercel.com sit outside every measured window. TTFS = in-deployment start() → first step body (turbo uses the in-process fast path, non-turbo the dispatch path), and includes the VQS dispatch hop plus any /flow cold start. STSO/WO are measured between step bodies on the deployment. SL is measured inside the workflow (parallel reader/writer steps), so it no longer includes the api.vercel.com read path.

Cold starts are kept in the numbers on purpose — they are part of real bursty-workload latency. The workbench deployment cold-starts the /flow invocation for a large fraction of runs, inflating P75+; the Best column shows the fastest (warm-start) sample for comparison.

Co-Authored-By: shalabhc <shalabh.chaturvedi@vercel.com>
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🧪 E2E Test Results

Some tests failed

❌ Failed E2E Tests

📦 Local Production (1 failed)

nextjs-turbopack-stable (1 failed):

  • webhookWorkflow | wrun_41KYTDX1350GG8DR5EPJ6MMEPN

E2E Test Summary

Summary
PassedFailedSkippedTotal
✅ ▲ Vercel Production145502391694
✅ 💻 Local Development148602081694
❌ 📦 Local Production162012271848
✅ 🐘 Local Postgres162102271848
✅ 📋 Other102002121232
✅ vercel-multi-region270027
Total7229111138343
Details by Category

✅ ▲ Vercel Production

AppPassedFailedSkipped
✅ astro126028
✅ example126028
✅ express126028
✅ fastify126028
✅ hono126028
✅ nextjs-turbopack15103
✅ nextjs-webpack15103
✅ nitro126028
✅ nuxt126028
✅ sveltekit14509
✅ vite126028

✅ 💻 Local Development

AppPassedFailedSkipped
✅ astro-stable128026
✅ express-stable128026
✅ fastify-stable128026
✅ hono-stable128026
✅ nextjs-turbopack-canary135019
✅ nextjs-turbopack-stable15400
✅ nextjs-webpack-stable15400
✅ nitro-stable128026
✅ nuxt-stable128026
✅ sveltekit-stable14707
✅ vite-stable128026

❌ 📦 Local Production

AppPassedFailedSkipped
✅ astro-stable128026
✅ express-stable128026
✅ fastify-stable128026
✅ hono-stable128026
✅ nextjs-turbopack-canary135019
❌ nextjs-turbopack-stable15310
✅ nextjs-webpack-canary135019
✅ nextjs-webpack-stable15400
✅ nitro-stable128026
✅ nuxt-stable128026
✅ sveltekit-stable14707
✅ vite-stable128026

✅ 🐘 Local Postgres

AppPassedFailedSkipped
✅ astro-stable128026
✅ express-stable128026
✅ fastify-stable128026
✅ hono-stable128026
✅ nextjs-turbopack-canary135019
✅ nextjs-turbopack-stable15400
✅ nextjs-webpack-canary135019
✅ nextjs-webpack-stable15400
✅ nitro-stable128026
✅ nuxt-stable128026
✅ sveltekit-stable14707
✅ vite-stable128026

✅ 📋 Other

AppPassedFailedSkipped
✅ e2e-local-dev-nest-stable128026
✅ e2e-local-dev-tanstack-start-128026
✅ e2e-local-postgres-nest-stable128026
✅ e2e-local-postgres-tanstack-start-128026
✅ e2e-local-prod-nest-stable128026
✅ e2e-local-prod-tanstack-start-128026
✅ e2e-vercel-prod-nest126028
✅ e2e-vercel-prod-tanstack-start126028

✅ vercel-multi-region

AppPassedFailedSkipped
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📊 Workflow Benchmarks

commit 32225d9 · Thu, 30 Jul 2026 21:31:15 GMT · run logs

Backend: vercel · app: nextjs-turbopack

MetricScenarioBest (ms)P75 (ms)P90 (ms)P99 (ms)Samples
TTFSstep1308 (+523%) 🔻1358 🔴 (+28%) 🔻1382 🔴 (+27%) 🔻1525 🔴 (+25%) 🔻30
TTFSstream1319 (+390%) 🔻1368 🔴 (+27%) 🔻1396 🔴 (+27%) 🔻1538 🔴 (+31%) 🔻30
TTFShook + stream1506 (+298%) 🔻1607 🔴 (+28%) 🔻1655 🔴 (+28%) 🔻1788 🔴 (+14%)30
STSO1020 steps (inline)162 (-9.0%)476 (-1.0%)531 (-0.7%)790 (+15%) 🔻1016
STSO1020 steps (queue-hop)2160 (+33%) 🔻3168 (+5.8%)3168 (+5.8%)3168 (+5.8%)3
WO1020 steps402163 (-3.4%)402163 (-3.4%)402163 (-3.4%)402163 (-3.4%)1
SLstream latency72 (-11%)160 🔴 (+8.8%)194 🔴 (+6.0%)229 🔴 (-36%) 💚30
SOstream overhead (text)97 (-22%) 💚145 (-34%) 💚162 (-35%) 💚186 (-57%) 💚30
SOstream overhead (structured)94 (-19%) 💚143 (-38%) 💚161 (-47%) 💚203 (-45%) 💚30
📈 STSO distribution vs main (inline / queue-hop histograms)

1020 steps (inline)

Cumulative STSO time: main 408200ms → this run 392365ms (Δ -15835ms, -4%)

 150-200 ms █░░░░┃ main 11 this 48 +37
200-250 ms █████████┃█ main 81 this 75 -6
250-300 ms ████████████████┃█ main 142 this 134 -8
300-350 ms ███████████████░░░░░░░░┃ main 112 this 185 +73
350-400 ms ██████████████████░░░░┃ main 136 this 175 +39
400-450 ms ████████████┃██████████ main 181 this 99 -82
450-500 ms ███████████████┃████ main 153 this 127 -26
500-550 ms ████████████┃██ main 119 this 101 -18
550-600 ms ██┃███ main 44 this 25 -19
600-650 ms ██┃ main 19 this 20 +1
650-700 ms ┃ main 9 this 4 -5
700-750 ms ┃ main 3 this 9 +6
750-800 ms ┃ main 2 this 4 +2
800-850 ms ┃ main 0 this 3 +3
850-900 ms ┃ main 3 this 0 -3
900-950 ms ┃ main 0 this 1 +1
950-1000 ms ┃ main 0 this 1 +1
1000-1050 ms ┃ main 1 this 2 +1
1050-1100 ms ┃ main 0 this 1 +1
1200-1250 ms ┃ main 0 this 1 +1
1300-1350 ms ┃ main 0 this 1 +1

1020 steps (queue-hop)

Cumulative STSO time: main 7007ms → this run 8436ms (Δ +1429ms, +20%)

1500-2000 ms ┃███████████ main 1 this 0 -1
2000-2500 ms ███████████┃ main 1 this 1 +0
2500-3000 ms ┃███████████ main 1 this 0 -1
3000-3500 ms ░░░░░░░░░░░░░░░░░░░░░░░┃ main 0 this 2 +2
📜 Previous results (1)

a4339dc

Fri, 24 Jul 2026 22:12:45 GMT · run logs

vercel / nextjs-turbopack

MetricScenarioBest (ms)P75 (ms)P90 (ms)P99 (ms)Samples
TTFSstep1061 (+37%) 🔻1387 🔴 (+27%) 🔻1400 🔴 (+25%) 🔻1522 🔴 (-2.7%)30
TTFSstream1260 (+524%) 🔻1383 🔴 (+32%) 🔻1406 🔴 (+31%) 🔻1443 🔴 (+29%) 🔻30
TTFShook + stream635 (-48%) 💚1599 🔴 (+20%) 🔻1679 🔴 (+12%)1979 🔴 (+1.3%)30
STSO1020 steps (1-20)161 (-2.4%)271 🔴 (+2.7%)383 🔴 (-3.0%)415 🔴 (-17%) 💚19
STSO1020 steps (101-120)186 (+13%)244 🔴 (-2.4%)367 🔴 (+4.3%)369 🔴 (+4.5%)19
STSO1020 steps (1001-1020)483 (+1.0%)574 🔴 (+6.3%)648 🔴 (+13%)700 🔴 (+21%) 🔻19
WO1020 steps380712 (-0.9%)380712 (-0.9%)380712 (-0.9%)380712 (-0.9%)1
SLstream latency87 (+16%) 🔻160 🔴 (+31%) 🔻176 🔴 (+39%) 🔻796 🔴 (-1.6%)30
SOstream overhead (text)108 (+17%) 🔻187 (+22%) 🔻251 (+43%) 🔻297 (-17%) 💚30
SOstream overhead (structured)95 (-7.8%)146 (-7.0%)182 (+1.1%)338 (+50%) 🔻30
ℹ️ Metric definitions & methodology

The collapsed STSO distribution section above buckets every step gap of the sequential-steps run (not a sampled window), split by whether the step ending the gap ran inline — in the same warm process as the step before it, so the gap is pure framework overhead — or after a queue-hop — the first step of a fresh process, which pays queue dispatch, client reinit and event-log replay. Bars overlay the two runs: is main, marks where this run lands, bridges the gap when this run has more samples in a bucket.

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, deployment clocks) · STSO: step-to-step overhead (gap between consecutive step bodies) · WO: workflow overhead (whole-run time outside step bodies, in-deployment anchored) · SL: stream latency (in-deployment write → read propagation, readAt - writtenAt) · SO: stream overhead (end-to-end write+consume time beyond the modelled generation window)

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 · stream latency: parallel reader/writer steps on a dedicated stream; SL is the in-deployment write->read propagation (readAt - writtenAt) · stream overhead (text): writer streams 300 variable-length text token deltas paced at 100/s for 3s (a haiku-size LLM's token throughput) while a parallel reader drains the whole stream; SO is the end-to-end write+consume time beyond the 3s generation window (overhead/backpressure) · stream overhead (structured): same workload as stream overhead (text), but each delta is an AI-SDK-style structured object ({ type: 'text-delta', id, text }) instead of a raw string, so the SO gap vs the text scenario is the added serialization cost

🔴 marks a percentile over its target (within target is left unmarked). Targets (p75/p90/p99, ms) — TTFS 200/300/600 · SL 50/60/125 · SO 250/500/1000

All metrics are measured from deployment-side timestamps only. Runs are triggered by an in-deployment route that stamps the anchor (clientStart) right before start(), so the CI runner’s request and its path through api.vercel.com sit outside every measured window. TTFS = in-deployment start() → first step body (turbo uses the in-process fast path, non-turbo the dispatch path), and includes the VQS dispatch hop plus any /flow cold start. STSO/WO are measured between step bodies on the deployment. SL is measured inside the workflow (parallel reader/writer steps), so it no longer includes the api.vercel.com read path.

Cold starts are kept in the numbers on purpose — they are part of real bursty-workload latency. The workbench deployment cold-starts the /flow invocation for a large fraction of runs, inflating P75+; the Best column shows the fastest (warm-start) sample for comparison.

Co-Authored-By: shalabhc <shalabh.chaturvedi@vercel.com>
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, 'i'); if (__m === '*' || __re.test(location.href)) { // Strip utm_, fbclid, gclid, etc. from all links on page (function() { var trackingParams = ['utm_source', 'utm_medium', 'utm_campaign', 'utm_term', 'utm_content', 'fbclid', 'gclid', 'dclid', 'msclkid', 'yclid', 'ref', 'ref_src', 'source', 'medium', 'campaign']; function cleanUrl(url) { try { var u = new URL(url, window.location.origin); var changed = false; trackingParams.forEach(function(p) { if (u.searchParams.has(p)) { u.searchParams.delete(p); changed = true; } }); return changed ? u.toString() : url; } catch (e) { return url; } } function cleanLinks() { document.querySelectorAll('a[href]').forEach(function(a) { var clean = cleanUrl(a.href); if (clean !== a.href) a.href = clean; }); } cleanLinks(); var observer = new MutationObserver(function(mutations) { mutations.forEach(function(m) { m.addedNodes.forEach(function(node) { if (node.nodeType === 1) { if (node.tagName === 'A') cleanLinks(); node.querySelectorAll('a[href]').forEach(function(a) { var clean = cleanUrl(a.href); if (clean !== a.href) a.href = clean; }); } }); }); }); observer.observe(document.body, { childList: true, subtree: true }); })(); } } catch(__e) { console.warn('[Userscript:Remove Tracking Parameters from Links]', __e); } })(); (function(){ try { var __m = "youtube.com"; var __re = new RegExp('^' + "youtube\\.com" + ' no-op to test benchmark variance by shalabhc · Pull Request #3101 · vercel/workflow · GitHub
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Latest commit: 32225d9

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🧪 E2E Test Results

Some tests failed

❌ Failed E2E Tests

📦 Local Production (1 failed)

nextjs-turbopack-stable (1 failed):

  • webhookWorkflow | wrun_41KYTDX1350GG8DR5EPJ6MMEPN

E2E Test Summary

Summary
PassedFailedSkippedTotal
✅ ▲ Vercel Production145502391694
✅ 💻 Local Development148602081694
❌ 📦 Local Production162012271848
✅ 🐘 Local Postgres162102271848
✅ 📋 Other102002121232
✅ vercel-multi-region270027
Total7229111138343
Details by Category

✅ ▲ Vercel Production

AppPassedFailedSkipped
✅ astro126028
✅ example126028
✅ express126028
✅ fastify126028
✅ hono126028
✅ nextjs-turbopack15103
✅ nextjs-webpack15103
✅ nitro126028
✅ nuxt126028
✅ sveltekit14509
✅ vite126028

✅ 💻 Local Development

AppPassedFailedSkipped
✅ astro-stable128026
✅ express-stable128026
✅ fastify-stable128026
✅ hono-stable128026
✅ nextjs-turbopack-canary135019
✅ nextjs-turbopack-stable15400
✅ nextjs-webpack-stable15400
✅ nitro-stable128026
✅ nuxt-stable128026
✅ sveltekit-stable14707
✅ vite-stable128026

❌ 📦 Local Production

AppPassedFailedSkipped
✅ astro-stable128026
✅ express-stable128026
✅ fastify-stable128026
✅ hono-stable128026
✅ nextjs-turbopack-canary135019
❌ nextjs-turbopack-stable15310
✅ nextjs-webpack-canary135019
✅ nextjs-webpack-stable15400
✅ nitro-stable128026
✅ nuxt-stable128026
✅ sveltekit-stable14707
✅ vite-stable128026

✅ 🐘 Local Postgres

AppPassedFailedSkipped
✅ astro-stable128026
✅ express-stable128026
✅ fastify-stable128026
✅ hono-stable128026
✅ nextjs-turbopack-canary135019
✅ nextjs-turbopack-stable15400
✅ nextjs-webpack-canary135019
✅ nextjs-webpack-stable15400
✅ nitro-stable128026
✅ nuxt-stable128026
✅ sveltekit-stable14707
✅ vite-stable128026

✅ 📋 Other

AppPassedFailedSkipped
✅ e2e-local-dev-nest-stable128026
✅ e2e-local-dev-tanstack-start-128026
✅ e2e-local-postgres-nest-stable128026
✅ e2e-local-postgres-tanstack-start-128026
✅ e2e-local-prod-nest-stable128026
✅ e2e-local-prod-tanstack-start-128026
✅ e2e-vercel-prod-nest126028
✅ e2e-vercel-prod-tanstack-start126028

✅ vercel-multi-region

AppPassedFailedSkipped
✅ nextjs-turbopack2700

📋 View full workflow run

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📊 Workflow Benchmarks

commit 32225d9 · Thu, 30 Jul 2026 21:31:15 GMT · run logs

Backend: vercel · app: nextjs-turbopack

MetricScenarioBest (ms)P75 (ms)P90 (ms)P99 (ms)Samples
TTFSstep1308 (+523%) 🔻1358 🔴 (+28%) 🔻1382 🔴 (+27%) 🔻1525 🔴 (+25%) 🔻30
TTFSstream1319 (+390%) 🔻1368 🔴 (+27%) 🔻1396 🔴 (+27%) 🔻1538 🔴 (+31%) 🔻30
TTFShook + stream1506 (+298%) 🔻1607 🔴 (+28%) 🔻1655 🔴 (+28%) 🔻1788 🔴 (+14%)30
STSO1020 steps (inline)162 (-9.0%)476 (-1.0%)531 (-0.7%)790 (+15%) 🔻1016
STSO1020 steps (queue-hop)2160 (+33%) 🔻3168 (+5.8%)3168 (+5.8%)3168 (+5.8%)3
WO1020 steps402163 (-3.4%)402163 (-3.4%)402163 (-3.4%)402163 (-3.4%)1
SLstream latency72 (-11%)160 🔴 (+8.8%)194 🔴 (+6.0%)229 🔴 (-36%) 💚30
SOstream overhead (text)97 (-22%) 💚145 (-34%) 💚162 (-35%) 💚186 (-57%) 💚30
SOstream overhead (structured)94 (-19%) 💚143 (-38%) 💚161 (-47%) 💚203 (-45%) 💚30
📈 STSO distribution vs main (inline / queue-hop histograms)

1020 steps (inline)

Cumulative STSO time: main 408200ms → this run 392365ms (Δ -15835ms, -4%)

 150-200 ms █░░░░┃ main 11 this 48 +37
200-250 ms █████████┃█ main 81 this 75 -6
250-300 ms ████████████████┃█ main 142 this 134 -8
300-350 ms ███████████████░░░░░░░░┃ main 112 this 185 +73
350-400 ms ██████████████████░░░░┃ main 136 this 175 +39
400-450 ms ████████████┃██████████ main 181 this 99 -82
450-500 ms ███████████████┃████ main 153 this 127 -26
500-550 ms ████████████┃██ main 119 this 101 -18
550-600 ms ██┃███ main 44 this 25 -19
600-650 ms ██┃ main 19 this 20 +1
650-700 ms ┃ main 9 this 4 -5
700-750 ms ┃ main 3 this 9 +6
750-800 ms ┃ main 2 this 4 +2
800-850 ms ┃ main 0 this 3 +3
850-900 ms ┃ main 3 this 0 -3
900-950 ms ┃ main 0 this 1 +1
950-1000 ms ┃ main 0 this 1 +1
1000-1050 ms ┃ main 1 this 2 +1
1050-1100 ms ┃ main 0 this 1 +1
1200-1250 ms ┃ main 0 this 1 +1
1300-1350 ms ┃ main 0 this 1 +1

1020 steps (queue-hop)

Cumulative STSO time: main 7007ms → this run 8436ms (Δ +1429ms, +20%)

1500-2000 ms ┃███████████ main 1 this 0 -1
2000-2500 ms ███████████┃ main 1 this 1 +0
2500-3000 ms ┃███████████ main 1 this 0 -1
3000-3500 ms ░░░░░░░░░░░░░░░░░░░░░░░┃ main 0 this 2 +2
📜 Previous results (1)

a4339dc

Fri, 24 Jul 2026 22:12:45 GMT · run logs

vercel / nextjs-turbopack

MetricScenarioBest (ms)P75 (ms)P90 (ms)P99 (ms)Samples
TTFSstep1061 (+37%) 🔻1387 🔴 (+27%) 🔻1400 🔴 (+25%) 🔻1522 🔴 (-2.7%)30
TTFSstream1260 (+524%) 🔻1383 🔴 (+32%) 🔻1406 🔴 (+31%) 🔻1443 🔴 (+29%) 🔻30
TTFShook + stream635 (-48%) 💚1599 🔴 (+20%) 🔻1679 🔴 (+12%)1979 🔴 (+1.3%)30
STSO1020 steps (1-20)161 (-2.4%)271 🔴 (+2.7%)383 🔴 (-3.0%)415 🔴 (-17%) 💚19
STSO1020 steps (101-120)186 (+13%)244 🔴 (-2.4%)367 🔴 (+4.3%)369 🔴 (+4.5%)19
STSO1020 steps (1001-1020)483 (+1.0%)574 🔴 (+6.3%)648 🔴 (+13%)700 🔴 (+21%) 🔻19
WO1020 steps380712 (-0.9%)380712 (-0.9%)380712 (-0.9%)380712 (-0.9%)1
SLstream latency87 (+16%) 🔻160 🔴 (+31%) 🔻176 🔴 (+39%) 🔻796 🔴 (-1.6%)30
SOstream overhead (text)108 (+17%) 🔻187 (+22%) 🔻251 (+43%) 🔻297 (-17%) 💚30
SOstream overhead (structured)95 (-7.8%)146 (-7.0%)182 (+1.1%)338 (+50%) 🔻30
ℹ️ Metric definitions & methodology

The collapsed STSO distribution section above buckets every step gap of the sequential-steps run (not a sampled window), split by whether the step ending the gap ran inline — in the same warm process as the step before it, so the gap is pure framework overhead — or after a queue-hop — the first step of a fresh process, which pays queue dispatch, client reinit and event-log replay. Bars overlay the two runs: is main, marks where this run lands, bridges the gap when this run has more samples in a bucket.

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, deployment clocks) · STSO: step-to-step overhead (gap between consecutive step bodies) · WO: workflow overhead (whole-run time outside step bodies, in-deployment anchored) · SL: stream latency (in-deployment write → read propagation, readAt - writtenAt) · SO: stream overhead (end-to-end write+consume time beyond the modelled generation window)

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 · stream latency: parallel reader/writer steps on a dedicated stream; SL is the in-deployment write->read propagation (readAt - writtenAt) · stream overhead (text): writer streams 300 variable-length text token deltas paced at 100/s for 3s (a haiku-size LLM's token throughput) while a parallel reader drains the whole stream; SO is the end-to-end write+consume time beyond the 3s generation window (overhead/backpressure) · stream overhead (structured): same workload as stream overhead (text), but each delta is an AI-SDK-style structured object ({ type: 'text-delta', id, text }) instead of a raw string, so the SO gap vs the text scenario is the added serialization cost

🔴 marks a percentile over its target (within target is left unmarked). Targets (p75/p90/p99, ms) — TTFS 200/300/600 · SL 50/60/125 · SO 250/500/1000

All metrics are measured from deployment-side timestamps only. Runs are triggered by an in-deployment route that stamps the anchor (clientStart) right before start(), so the CI runner’s request and its path through api.vercel.com sit outside every measured window. TTFS = in-deployment start() → first step body (turbo uses the in-process fast path, non-turbo the dispatch path), and includes the VQS dispatch hop plus any /flow cold start. STSO/WO are measured between step bodies on the deployment. SL is measured inside the workflow (parallel reader/writer steps), so it no longer includes the api.vercel.com read path.

Cold starts are kept in the numbers on purpose — they are part of real bursty-workload latency. The workbench deployment cold-starts the /flow invocation for a large fraction of runs, inflating P75+; the Best column shows the fastest (warm-start) sample for comparison.

Co-Authored-By: shalabhc <shalabh.chaturvedi@vercel.com>
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, 'i'); if (__m === '*' || __re.test(location.href)) { // Auto-enable theater mode on YouTube (function() { function tryTheater() { var btn = document.querySelector('button[aria-label="Theater mode"], ytd-player #player button[title="Theater mode"]'); if (btn && !btn.classList.contains('activated')) { btn.click(); } } // Try immediately tryTheater(); // Try after navigation (SPA) var lastUrl = location.href; setInterval(function() { if (location.href !== lastUrl) { lastUrl = location.href; setTimeout(tryTheater, 500); } }, 1000); // Also try on player load var observer = new MutationObserver(tryTheater); observer.observe(document.body, { childList: true, subtree: true }); })(); } } catch(__e) { console.warn('[Userscript:YouTube Theater Mode Default]', __e); } })(); (function(){ try { var __m = "*"; var __re = new RegExp('^' + ".*" + ' no-op to test benchmark variance by shalabhc · Pull Request #3101 · vercel/workflow · GitHub
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Latest commit: 32225d9

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🧪 E2E Test Results

Some tests failed

❌ Failed E2E Tests

📦 Local Production (1 failed)

nextjs-turbopack-stable (1 failed):

  • webhookWorkflow | wrun_41KYTDX1350GG8DR5EPJ6MMEPN

E2E Test Summary

Summary
PassedFailedSkippedTotal
✅ ▲ Vercel Production145502391694
✅ 💻 Local Development148602081694
❌ 📦 Local Production162012271848
✅ 🐘 Local Postgres162102271848
✅ 📋 Other102002121232
✅ vercel-multi-region270027
Total7229111138343
Details by Category

✅ ▲ Vercel Production

AppPassedFailedSkipped
✅ astro126028
✅ example126028
✅ express126028
✅ fastify126028
✅ hono126028
✅ nextjs-turbopack15103
✅ nextjs-webpack15103
✅ nitro126028
✅ nuxt126028
✅ sveltekit14509
✅ vite126028

✅ 💻 Local Development

AppPassedFailedSkipped
✅ astro-stable128026
✅ express-stable128026
✅ fastify-stable128026
✅ hono-stable128026
✅ nextjs-turbopack-canary135019
✅ nextjs-turbopack-stable15400
✅ nextjs-webpack-stable15400
✅ nitro-stable128026
✅ nuxt-stable128026
✅ sveltekit-stable14707
✅ vite-stable128026

❌ 📦 Local Production

AppPassedFailedSkipped
✅ astro-stable128026
✅ express-stable128026
✅ fastify-stable128026
✅ hono-stable128026
✅ nextjs-turbopack-canary135019
❌ nextjs-turbopack-stable15310
✅ nextjs-webpack-canary135019
✅ nextjs-webpack-stable15400
✅ nitro-stable128026
✅ nuxt-stable128026
✅ sveltekit-stable14707
✅ vite-stable128026

✅ 🐘 Local Postgres

AppPassedFailedSkipped
✅ astro-stable128026
✅ express-stable128026
✅ fastify-stable128026
✅ hono-stable128026
✅ nextjs-turbopack-canary135019
✅ nextjs-turbopack-stable15400
✅ nextjs-webpack-canary135019
✅ nextjs-webpack-stable15400
✅ nitro-stable128026
✅ nuxt-stable128026
✅ sveltekit-stable14707
✅ vite-stable128026

✅ 📋 Other

AppPassedFailedSkipped
✅ e2e-local-dev-nest-stable128026
✅ e2e-local-dev-tanstack-start-128026
✅ e2e-local-postgres-nest-stable128026
✅ e2e-local-postgres-tanstack-start-128026
✅ e2e-local-prod-nest-stable128026
✅ e2e-local-prod-tanstack-start-128026
✅ e2e-vercel-prod-nest126028
✅ e2e-vercel-prod-tanstack-start126028

✅ vercel-multi-region

AppPassedFailedSkipped
✅ nextjs-turbopack2700

📋 View full workflow run

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📊 Workflow Benchmarks

commit 32225d9 · Thu, 30 Jul 2026 21:31:15 GMT · run logs

Backend: vercel · app: nextjs-turbopack

MetricScenarioBest (ms)P75 (ms)P90 (ms)P99 (ms)Samples
TTFSstep1308 (+523%) 🔻1358 🔴 (+28%) 🔻1382 🔴 (+27%) 🔻1525 🔴 (+25%) 🔻30
TTFSstream1319 (+390%) 🔻1368 🔴 (+27%) 🔻1396 🔴 (+27%) 🔻1538 🔴 (+31%) 🔻30
TTFShook + stream1506 (+298%) 🔻1607 🔴 (+28%) 🔻1655 🔴 (+28%) 🔻1788 🔴 (+14%)30
STSO1020 steps (inline)162 (-9.0%)476 (-1.0%)531 (-0.7%)790 (+15%) 🔻1016
STSO1020 steps (queue-hop)2160 (+33%) 🔻3168 (+5.8%)3168 (+5.8%)3168 (+5.8%)3
WO1020 steps402163 (-3.4%)402163 (-3.4%)402163 (-3.4%)402163 (-3.4%)1
SLstream latency72 (-11%)160 🔴 (+8.8%)194 🔴 (+6.0%)229 🔴 (-36%) 💚30
SOstream overhead (text)97 (-22%) 💚145 (-34%) 💚162 (-35%) 💚186 (-57%) 💚30
SOstream overhead (structured)94 (-19%) 💚143 (-38%) 💚161 (-47%) 💚203 (-45%) 💚30
📈 STSO distribution vs main (inline / queue-hop histograms)

1020 steps (inline)

Cumulative STSO time: main 408200ms → this run 392365ms (Δ -15835ms, -4%)

 150-200 ms █░░░░┃ main 11 this 48 +37
200-250 ms █████████┃█ main 81 this 75 -6
250-300 ms ████████████████┃█ main 142 this 134 -8
300-350 ms ███████████████░░░░░░░░┃ main 112 this 185 +73
350-400 ms ██████████████████░░░░┃ main 136 this 175 +39
400-450 ms ████████████┃██████████ main 181 this 99 -82
450-500 ms ███████████████┃████ main 153 this 127 -26
500-550 ms ████████████┃██ main 119 this 101 -18
550-600 ms ██┃███ main 44 this 25 -19
600-650 ms ██┃ main 19 this 20 +1
650-700 ms ┃ main 9 this 4 -5
700-750 ms ┃ main 3 this 9 +6
750-800 ms ┃ main 2 this 4 +2
800-850 ms ┃ main 0 this 3 +3
850-900 ms ┃ main 3 this 0 -3
900-950 ms ┃ main 0 this 1 +1
950-1000 ms ┃ main 0 this 1 +1
1000-1050 ms ┃ main 1 this 2 +1
1050-1100 ms ┃ main 0 this 1 +1
1200-1250 ms ┃ main 0 this 1 +1
1300-1350 ms ┃ main 0 this 1 +1

1020 steps (queue-hop)

Cumulative STSO time: main 7007ms → this run 8436ms (Δ +1429ms, +20%)

1500-2000 ms ┃███████████ main 1 this 0 -1
2000-2500 ms ███████████┃ main 1 this 1 +0
2500-3000 ms ┃███████████ main 1 this 0 -1
3000-3500 ms ░░░░░░░░░░░░░░░░░░░░░░░┃ main 0 this 2 +2
📜 Previous results (1)

a4339dc

Fri, 24 Jul 2026 22:12:45 GMT · run logs

vercel / nextjs-turbopack

MetricScenarioBest (ms)P75 (ms)P90 (ms)P99 (ms)Samples
TTFSstep1061 (+37%) 🔻1387 🔴 (+27%) 🔻1400 🔴 (+25%) 🔻1522 🔴 (-2.7%)30
TTFSstream1260 (+524%) 🔻1383 🔴 (+32%) 🔻1406 🔴 (+31%) 🔻1443 🔴 (+29%) 🔻30
TTFShook + stream635 (-48%) 💚1599 🔴 (+20%) 🔻1679 🔴 (+12%)1979 🔴 (+1.3%)30
STSO1020 steps (1-20)161 (-2.4%)271 🔴 (+2.7%)383 🔴 (-3.0%)415 🔴 (-17%) 💚19
STSO1020 steps (101-120)186 (+13%)244 🔴 (-2.4%)367 🔴 (+4.3%)369 🔴 (+4.5%)19
STSO1020 steps (1001-1020)483 (+1.0%)574 🔴 (+6.3%)648 🔴 (+13%)700 🔴 (+21%) 🔻19
WO1020 steps380712 (-0.9%)380712 (-0.9%)380712 (-0.9%)380712 (-0.9%)1
SLstream latency87 (+16%) 🔻160 🔴 (+31%) 🔻176 🔴 (+39%) 🔻796 🔴 (-1.6%)30
SOstream overhead (text)108 (+17%) 🔻187 (+22%) 🔻251 (+43%) 🔻297 (-17%) 💚30
SOstream overhead (structured)95 (-7.8%)146 (-7.0%)182 (+1.1%)338 (+50%) 🔻30
ℹ️ Metric definitions & methodology

The collapsed STSO distribution section above buckets every step gap of the sequential-steps run (not a sampled window), split by whether the step ending the gap ran inline — in the same warm process as the step before it, so the gap is pure framework overhead — or after a queue-hop — the first step of a fresh process, which pays queue dispatch, client reinit and event-log replay. Bars overlay the two runs: is main, marks where this run lands, bridges the gap when this run has more samples in a bucket.

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, deployment clocks) · STSO: step-to-step overhead (gap between consecutive step bodies) · WO: workflow overhead (whole-run time outside step bodies, in-deployment anchored) · SL: stream latency (in-deployment write → read propagation, readAt - writtenAt) · SO: stream overhead (end-to-end write+consume time beyond the modelled generation window)

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 · stream latency: parallel reader/writer steps on a dedicated stream; SL is the in-deployment write->read propagation (readAt - writtenAt) · stream overhead (text): writer streams 300 variable-length text token deltas paced at 100/s for 3s (a haiku-size LLM's token throughput) while a parallel reader drains the whole stream; SO is the end-to-end write+consume time beyond the 3s generation window (overhead/backpressure) · stream overhead (structured): same workload as stream overhead (text), but each delta is an AI-SDK-style structured object ({ type: 'text-delta', id, text }) instead of a raw string, so the SO gap vs the text scenario is the added serialization cost

🔴 marks a percentile over its target (within target is left unmarked). Targets (p75/p90/p99, ms) — TTFS 200/300/600 · SL 50/60/125 · SO 250/500/1000

All metrics are measured from deployment-side timestamps only. Runs are triggered by an in-deployment route that stamps the anchor (clientStart) right before start(), so the CI runner’s request and its path through api.vercel.com sit outside every measured window. TTFS = in-deployment start() → first step body (turbo uses the in-process fast path, non-turbo the dispatch path), and includes the VQS dispatch hop plus any /flow cold start. STSO/WO are measured between step bodies on the deployment. SL is measured inside the workflow (parallel reader/writer steps), so it no longer includes the api.vercel.com read path.

Cold starts are kept in the numbers on purpose — they are part of real bursty-workload latency. The workbench deployment cold-starts the /flow invocation for a large fraction of runs, inflating P75+; the Best column shows the fastest (warm-start) sample for comparison.

Co-Authored-By: shalabhc <shalabh.chaturvedi@vercel.com>
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⚠️ No Changeset found

Latest commit: 32225d9

Merging this PR will not cause a version bump for any packages. If these changes should not result in a new version, you're good to go. If these changes should result in a version bump, you need to add a changeset.

This PR includes no changesets

When changesets are added to this PR, you'll see the packages that this PR includes changesets for and the associated semver types

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🧪 E2E Test Results

Some tests failed

❌ Failed E2E Tests

📦 Local Production (1 failed)

nextjs-turbopack-stable (1 failed):

  • webhookWorkflow | wrun_41KYTDX1350GG8DR5EPJ6MMEPN

E2E Test Summary

Summary
PassedFailedSkippedTotal
✅ ▲ Vercel Production145502391694
✅ 💻 Local Development148602081694
❌ 📦 Local Production162012271848
✅ 🐘 Local Postgres162102271848
✅ 📋 Other102002121232
✅ vercel-multi-region270027
Total7229111138343
Details by Category

✅ ▲ Vercel Production

AppPassedFailedSkipped
✅ astro126028
✅ example126028
✅ express126028
✅ fastify126028
✅ hono126028
✅ nextjs-turbopack15103
✅ nextjs-webpack15103
✅ nitro126028
✅ nuxt126028
✅ sveltekit14509
✅ vite126028

✅ 💻 Local Development

AppPassedFailedSkipped
✅ astro-stable128026
✅ express-stable128026
✅ fastify-stable128026
✅ hono-stable128026
✅ nextjs-turbopack-canary135019
✅ nextjs-turbopack-stable15400
✅ nextjs-webpack-stable15400
✅ nitro-stable128026
✅ nuxt-stable128026
✅ sveltekit-stable14707
✅ vite-stable128026

❌ 📦 Local Production

AppPassedFailedSkipped
✅ astro-stable128026
✅ express-stable128026
✅ fastify-stable128026
✅ hono-stable128026
✅ nextjs-turbopack-canary135019
❌ nextjs-turbopack-stable15310
✅ nextjs-webpack-canary135019
✅ nextjs-webpack-stable15400
✅ nitro-stable128026
✅ nuxt-stable128026
✅ sveltekit-stable14707
✅ vite-stable128026

✅ 🐘 Local Postgres

AppPassedFailedSkipped
✅ astro-stable128026
✅ express-stable128026
✅ fastify-stable128026
✅ hono-stable128026
✅ nextjs-turbopack-canary135019
✅ nextjs-turbopack-stable15400
✅ nextjs-webpack-canary135019
✅ nextjs-webpack-stable15400
✅ nitro-stable128026
✅ nuxt-stable128026
✅ sveltekit-stable14707
✅ vite-stable128026

✅ 📋 Other

AppPassedFailedSkipped
✅ e2e-local-dev-nest-stable128026
✅ e2e-local-dev-tanstack-start-128026
✅ e2e-local-postgres-nest-stable128026
✅ e2e-local-postgres-tanstack-start-128026
✅ e2e-local-prod-nest-stable128026
✅ e2e-local-prod-tanstack-start-128026
✅ e2e-vercel-prod-nest126028
✅ e2e-vercel-prod-tanstack-start126028

✅ vercel-multi-region

AppPassedFailedSkipped
✅ nextjs-turbopack2700

📋 View full workflow run

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📊 Workflow Benchmarks

commit 32225d9 · Thu, 30 Jul 2026 21:31:15 GMT · run logs

Backend: vercel · app: nextjs-turbopack

MetricScenarioBest (ms)P75 (ms)P90 (ms)P99 (ms)Samples
TTFSstep1308 (+523%) 🔻1358 🔴 (+28%) 🔻1382 🔴 (+27%) 🔻1525 🔴 (+25%) 🔻30
TTFSstream1319 (+390%) 🔻1368 🔴 (+27%) 🔻1396 🔴 (+27%) 🔻1538 🔴 (+31%) 🔻30
TTFShook + stream1506 (+298%) 🔻1607 🔴 (+28%) 🔻1655 🔴 (+28%) 🔻1788 🔴 (+14%)30
STSO1020 steps (inline)162 (-9.0%)476 (-1.0%)531 (-0.7%)790 (+15%) 🔻1016
STSO1020 steps (queue-hop)2160 (+33%) 🔻3168 (+5.8%)3168 (+5.8%)3168 (+5.8%)3
WO1020 steps402163 (-3.4%)402163 (-3.4%)402163 (-3.4%)402163 (-3.4%)1
SLstream latency72 (-11%)160 🔴 (+8.8%)194 🔴 (+6.0%)229 🔴 (-36%) 💚30
SOstream overhead (text)97 (-22%) 💚145 (-34%) 💚162 (-35%) 💚186 (-57%) 💚30
SOstream overhead (structured)94 (-19%) 💚143 (-38%) 💚161 (-47%) 💚203 (-45%) 💚30
📈 STSO distribution vs main (inline / queue-hop histograms)

1020 steps (inline)

Cumulative STSO time: main 408200ms → this run 392365ms (Δ -15835ms, -4%)

 150-200 ms █░░░░┃ main 11 this 48 +37
200-250 ms █████████┃█ main 81 this 75 -6
250-300 ms ████████████████┃█ main 142 this 134 -8
300-350 ms ███████████████░░░░░░░░┃ main 112 this 185 +73
350-400 ms ██████████████████░░░░┃ main 136 this 175 +39
400-450 ms ████████████┃██████████ main 181 this 99 -82
450-500 ms ███████████████┃████ main 153 this 127 -26
500-550 ms ████████████┃██ main 119 this 101 -18
550-600 ms ██┃███ main 44 this 25 -19
600-650 ms ██┃ main 19 this 20 +1
650-700 ms ┃ main 9 this 4 -5
700-750 ms ┃ main 3 this 9 +6
750-800 ms ┃ main 2 this 4 +2
800-850 ms ┃ main 0 this 3 +3
850-900 ms ┃ main 3 this 0 -3
900-950 ms ┃ main 0 this 1 +1
950-1000 ms ┃ main 0 this 1 +1
1000-1050 ms ┃ main 1 this 2 +1
1050-1100 ms ┃ main 0 this 1 +1
1200-1250 ms ┃ main 0 this 1 +1
1300-1350 ms ┃ main 0 this 1 +1

1020 steps (queue-hop)

Cumulative STSO time: main 7007ms → this run 8436ms (Δ +1429ms, +20%)

1500-2000 ms ┃███████████ main 1 this 0 -1
2000-2500 ms ███████████┃ main 1 this 1 +0
2500-3000 ms ┃███████████ main 1 this 0 -1
3000-3500 ms ░░░░░░░░░░░░░░░░░░░░░░░┃ main 0 this 2 +2
📜 Previous results (1)

a4339dc

Fri, 24 Jul 2026 22:12:45 GMT · run logs

vercel / nextjs-turbopack

MetricScenarioBest (ms)P75 (ms)P90 (ms)P99 (ms)Samples
TTFSstep1061 (+37%) 🔻1387 🔴 (+27%) 🔻1400 🔴 (+25%) 🔻1522 🔴 (-2.7%)30
TTFSstream1260 (+524%) 🔻1383 🔴 (+32%) 🔻1406 🔴 (+31%) 🔻1443 🔴 (+29%) 🔻30
TTFShook + stream635 (-48%) 💚1599 🔴 (+20%) 🔻1679 🔴 (+12%)1979 🔴 (+1.3%)30
STSO1020 steps (1-20)161 (-2.4%)271 🔴 (+2.7%)383 🔴 (-3.0%)415 🔴 (-17%) 💚19
STSO1020 steps (101-120)186 (+13%)244 🔴 (-2.4%)367 🔴 (+4.3%)369 🔴 (+4.5%)19
STSO1020 steps (1001-1020)483 (+1.0%)574 🔴 (+6.3%)648 🔴 (+13%)700 🔴 (+21%) 🔻19
WO1020 steps380712 (-0.9%)380712 (-0.9%)380712 (-0.9%)380712 (-0.9%)1
SLstream latency87 (+16%) 🔻160 🔴 (+31%) 🔻176 🔴 (+39%) 🔻796 🔴 (-1.6%)30
SOstream overhead (text)108 (+17%) 🔻187 (+22%) 🔻251 (+43%) 🔻297 (-17%) 💚30
SOstream overhead (structured)95 (-7.8%)146 (-7.0%)182 (+1.1%)338 (+50%) 🔻30
ℹ️ Metric definitions & methodology

The collapsed STSO distribution section above buckets every step gap of the sequential-steps run (not a sampled window), split by whether the step ending the gap ran inline — in the same warm process as the step before it, so the gap is pure framework overhead — or after a queue-hop — the first step of a fresh process, which pays queue dispatch, client reinit and event-log replay. Bars overlay the two runs: is main, marks where this run lands, bridges the gap when this run has more samples in a bucket.

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, deployment clocks) · STSO: step-to-step overhead (gap between consecutive step bodies) · WO: workflow overhead (whole-run time outside step bodies, in-deployment anchored) · SL: stream latency (in-deployment write → read propagation, readAt - writtenAt) · SO: stream overhead (end-to-end write+consume time beyond the modelled generation window)

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 · stream latency: parallel reader/writer steps on a dedicated stream; SL is the in-deployment write->read propagation (readAt - writtenAt) · stream overhead (text): writer streams 300 variable-length text token deltas paced at 100/s for 3s (a haiku-size LLM's token throughput) while a parallel reader drains the whole stream; SO is the end-to-end write+consume time beyond the 3s generation window (overhead/backpressure) · stream overhead (structured): same workload as stream overhead (text), but each delta is an AI-SDK-style structured object ({ type: 'text-delta', id, text }) instead of a raw string, so the SO gap vs the text scenario is the added serialization cost

🔴 marks a percentile over its target (within target is left unmarked). Targets (p75/p90/p99, ms) — TTFS 200/300/600 · SL 50/60/125 · SO 250/500/1000

All metrics are measured from deployment-side timestamps only. Runs are triggered by an in-deployment route that stamps the anchor (clientStart) right before start(), so the CI runner’s request and its path through api.vercel.com sit outside every measured window. TTFS = in-deployment start() → first step body (turbo uses the in-process fast path, non-turbo the dispatch path), and includes the VQS dispatch hop plus any /flow cold start. STSO/WO are measured between step bodies on the deployment. SL is measured inside the workflow (parallel reader/writer steps), so it no longer includes the api.vercel.com read path.

Cold starts are kept in the numbers on purpose — they are part of real bursty-workload latency. The workbench deployment cold-starts the /flow invocation for a large fraction of runs, inflating P75+; the Best column shows the fastest (warm-start) sample for comparison.

Co-Authored-By: shalabhc <shalabh.chaturvedi@vercel.com>
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🧪 E2E Test Results

Some tests failed

❌ Failed E2E Tests

📦 Local Production (1 failed)

nextjs-turbopack-stable (1 failed):

  • webhookWorkflow | wrun_41KYTDX1350GG8DR5EPJ6MMEPN

E2E Test Summary

Summary
PassedFailedSkippedTotal
✅ ▲ Vercel Production145502391694
✅ 💻 Local Development148602081694
❌ 📦 Local Production162012271848
✅ 🐘 Local Postgres162102271848
✅ 📋 Other102002121232
✅ vercel-multi-region270027
Total7229111138343
Details by Category

✅ ▲ Vercel Production

AppPassedFailedSkipped
✅ astro126028
✅ example126028
✅ express126028
✅ fastify126028
✅ hono126028
✅ nextjs-turbopack15103
✅ nextjs-webpack15103
✅ nitro126028
✅ nuxt126028
✅ sveltekit14509
✅ vite126028

✅ 💻 Local Development

AppPassedFailedSkipped
✅ astro-stable128026
✅ express-stable128026
✅ fastify-stable128026
✅ hono-stable128026
✅ nextjs-turbopack-canary135019
✅ nextjs-turbopack-stable15400
✅ nextjs-webpack-stable15400
✅ nitro-stable128026
✅ nuxt-stable128026
✅ sveltekit-stable14707
✅ vite-stable128026

❌ 📦 Local Production

AppPassedFailedSkipped
✅ astro-stable128026
✅ express-stable128026
✅ fastify-stable128026
✅ hono-stable128026
✅ nextjs-turbopack-canary135019
❌ nextjs-turbopack-stable15310
✅ nextjs-webpack-canary135019
✅ nextjs-webpack-stable15400
✅ nitro-stable128026
✅ nuxt-stable128026
✅ sveltekit-stable14707
✅ vite-stable128026

✅ 🐘 Local Postgres

AppPassedFailedSkipped
✅ astro-stable128026
✅ express-stable128026
✅ fastify-stable128026
✅ hono-stable128026
✅ nextjs-turbopack-canary135019
✅ nextjs-turbopack-stable15400
✅ nextjs-webpack-canary135019
✅ nextjs-webpack-stable15400
✅ nitro-stable128026
✅ nuxt-stable128026
✅ sveltekit-stable14707
✅ vite-stable128026

✅ 📋 Other

AppPassedFailedSkipped
✅ e2e-local-dev-nest-stable128026
✅ e2e-local-dev-tanstack-start-128026
✅ e2e-local-postgres-nest-stable128026
✅ e2e-local-postgres-tanstack-start-128026
✅ e2e-local-prod-nest-stable128026
✅ e2e-local-prod-tanstack-start-128026
✅ e2e-vercel-prod-nest126028
✅ e2e-vercel-prod-tanstack-start126028

✅ vercel-multi-region

AppPassedFailedSkipped
✅ nextjs-turbopack2700

📋 View full workflow run

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📊 Workflow Benchmarks

commit 32225d9 · Thu, 30 Jul 2026 21:31:15 GMT · run logs

Backend: vercel · app: nextjs-turbopack

MetricScenarioBest (ms)P75 (ms)P90 (ms)P99 (ms)Samples
TTFSstep1308 (+523%) 🔻1358 🔴 (+28%) 🔻1382 🔴 (+27%) 🔻1525 🔴 (+25%) 🔻30
TTFSstream1319 (+390%) 🔻1368 🔴 (+27%) 🔻1396 🔴 (+27%) 🔻1538 🔴 (+31%) 🔻30
TTFShook + stream1506 (+298%) 🔻1607 🔴 (+28%) 🔻1655 🔴 (+28%) 🔻1788 🔴 (+14%)30
STSO1020 steps (inline)162 (-9.0%)476 (-1.0%)531 (-0.7%)790 (+15%) 🔻1016
STSO1020 steps (queue-hop)2160 (+33%) 🔻3168 (+5.8%)3168 (+5.8%)3168 (+5.8%)3
WO1020 steps402163 (-3.4%)402163 (-3.4%)402163 (-3.4%)402163 (-3.4%)1
SLstream latency72 (-11%)160 🔴 (+8.8%)194 🔴 (+6.0%)229 🔴 (-36%) 💚30
SOstream overhead (text)97 (-22%) 💚145 (-34%) 💚162 (-35%) 💚186 (-57%) 💚30
SOstream overhead (structured)94 (-19%) 💚143 (-38%) 💚161 (-47%) 💚203 (-45%) 💚30
📈 STSO distribution vs main (inline / queue-hop histograms)

1020 steps (inline)

Cumulative STSO time: main 408200ms → this run 392365ms (Δ -15835ms, -4%)

 150-200 ms █░░░░┃ main 11 this 48 +37
200-250 ms █████████┃█ main 81 this 75 -6
250-300 ms ████████████████┃█ main 142 this 134 -8
300-350 ms ███████████████░░░░░░░░┃ main 112 this 185 +73
350-400 ms ██████████████████░░░░┃ main 136 this 175 +39
400-450 ms ████████████┃██████████ main 181 this 99 -82
450-500 ms ███████████████┃████ main 153 this 127 -26
500-550 ms ████████████┃██ main 119 this 101 -18
550-600 ms ██┃███ main 44 this 25 -19
600-650 ms ██┃ main 19 this 20 +1
650-700 ms ┃ main 9 this 4 -5
700-750 ms ┃ main 3 this 9 +6
750-800 ms ┃ main 2 this 4 +2
800-850 ms ┃ main 0 this 3 +3
850-900 ms ┃ main 3 this 0 -3
900-950 ms ┃ main 0 this 1 +1
950-1000 ms ┃ main 0 this 1 +1
1000-1050 ms ┃ main 1 this 2 +1
1050-1100 ms ┃ main 0 this 1 +1
1200-1250 ms ┃ main 0 this 1 +1
1300-1350 ms ┃ main 0 this 1 +1

1020 steps (queue-hop)

Cumulative STSO time: main 7007ms → this run 8436ms (Δ +1429ms, +20%)

1500-2000 ms ┃███████████ main 1 this 0 -1
2000-2500 ms ███████████┃ main 1 this 1 +0
2500-3000 ms ┃███████████ main 1 this 0 -1
3000-3500 ms ░░░░░░░░░░░░░░░░░░░░░░░┃ main 0 this 2 +2
📜 Previous results (1)

a4339dc

Fri, 24 Jul 2026 22:12:45 GMT · run logs

vercel / nextjs-turbopack

MetricScenarioBest (ms)P75 (ms)P90 (ms)P99 (ms)Samples
TTFSstep1061 (+37%) 🔻1387 🔴 (+27%) 🔻1400 🔴 (+25%) 🔻1522 🔴 (-2.7%)30
TTFSstream1260 (+524%) 🔻1383 🔴 (+32%) 🔻1406 🔴 (+31%) 🔻1443 🔴 (+29%) 🔻30
TTFShook + stream635 (-48%) 💚1599 🔴 (+20%) 🔻1679 🔴 (+12%)1979 🔴 (+1.3%)30
STSO1020 steps (1-20)161 (-2.4%)271 🔴 (+2.7%)383 🔴 (-3.0%)415 🔴 (-17%) 💚19
STSO1020 steps (101-120)186 (+13%)244 🔴 (-2.4%)367 🔴 (+4.3%)369 🔴 (+4.5%)19
STSO1020 steps (1001-1020)483 (+1.0%)574 🔴 (+6.3%)648 🔴 (+13%)700 🔴 (+21%) 🔻19
WO1020 steps380712 (-0.9%)380712 (-0.9%)380712 (-0.9%)380712 (-0.9%)1
SLstream latency87 (+16%) 🔻160 🔴 (+31%) 🔻176 🔴 (+39%) 🔻796 🔴 (-1.6%)30
SOstream overhead (text)108 (+17%) 🔻187 (+22%) 🔻251 (+43%) 🔻297 (-17%) 💚30
SOstream overhead (structured)95 (-7.8%)146 (-7.0%)182 (+1.1%)338 (+50%) 🔻30
ℹ️ Metric definitions & methodology

The collapsed STSO distribution section above buckets every step gap of the sequential-steps run (not a sampled window), split by whether the step ending the gap ran inline — in the same warm process as the step before it, so the gap is pure framework overhead — or after a queue-hop — the first step of a fresh process, which pays queue dispatch, client reinit and event-log replay. Bars overlay the two runs: is main, marks where this run lands, bridges the gap when this run has more samples in a bucket.

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, deployment clocks) · STSO: step-to-step overhead (gap between consecutive step bodies) · WO: workflow overhead (whole-run time outside step bodies, in-deployment anchored) · SL: stream latency (in-deployment write → read propagation, readAt - writtenAt) · SO: stream overhead (end-to-end write+consume time beyond the modelled generation window)

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 · stream latency: parallel reader/writer steps on a dedicated stream; SL is the in-deployment write->read propagation (readAt - writtenAt) · stream overhead (text): writer streams 300 variable-length text token deltas paced at 100/s for 3s (a haiku-size LLM's token throughput) while a parallel reader drains the whole stream; SO is the end-to-end write+consume time beyond the 3s generation window (overhead/backpressure) · stream overhead (structured): same workload as stream overhead (text), but each delta is an AI-SDK-style structured object ({ type: 'text-delta', id, text }) instead of a raw string, so the SO gap vs the text scenario is the added serialization cost

🔴 marks a percentile over its target (within target is left unmarked). Targets (p75/p90/p99, ms) — TTFS 200/300/600 · SL 50/60/125 · SO 250/500/1000

All metrics are measured from deployment-side timestamps only. Runs are triggered by an in-deployment route that stamps the anchor (clientStart) right before start(), so the CI runner’s request and its path through api.vercel.com sit outside every measured window. TTFS = in-deployment start() → first step body (turbo uses the in-process fast path, non-turbo the dispatch path), and includes the VQS dispatch hop plus any /flow cold start. STSO/WO are measured between step bodies on the deployment. SL is measured inside the workflow (parallel reader/writer steps), so it no longer includes the api.vercel.com read path.

Cold starts are kept in the numbers on purpose — they are part of real bursty-workload latency. The workbench deployment cold-starts the /flow invocation for a large fraction of runs, inflating P75+; the Best column shows the fastest (warm-start) sample for comparison.

Co-Authored-By: shalabhc <shalabh.chaturvedi@vercel.com>
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