Skip to content

Add lazy workflow/step discovery via deferredEntries in next#976

Merged
ijjk merged 17 commits intomainfrom
ijjk/lazy-deferred-entries
Feb 10, 2026
Merged

Add lazy workflow/step discovery via deferredEntries in next#976
ijjk merged 17 commits intomainfrom
ijjk/lazy-deferred-entries

Conversation

@ijjk
Copy link
Copy Markdown
Member

@ijjk ijjk commented Feb 7, 2026 •
edited
Loading

This is a revival of #640 which hooks into a new experimental feature I added in Next.js called deferredEntries and onBeforeDeferredEntries (vercel/next.js#88347).

That feature allows us to bring back lazy discovery as it avoids the race conditions and hacky promise locking in the loader approach we previously tried.

In a follow-up PR we will also update to no longer use esbuild for stepsbundling at all which will fix cases like this #766.

The eager discovery approach is still needed for older Next.js versions that don't have the deferredEntries feature.

x-ref: #523
x-ref: #469
x-ref: #691

@changeset-bot
Copy link
Copy Markdown

changeset-bot Bot commented Feb 7, 2026 •
edited
Loading

🦋 Changeset detected

Latest commit: f651f1b

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

This PR includes changesets to release 14 packages
Name Type
@workflow/builders Patch
@workflow/core Patch
@workflow/next Patch
@workflow/astro Patch
@workflow/cli Patch
@workflow/nest Patch
@workflow/nitro Patch
@workflow/rollup Patch
@workflow/sveltekit Patch
@workflow/vite Patch
@workflow/web-shared Patch
workflow Patch
@workflow/world-testing Patch
@workflow/nuxt Patch

Not sure what this means? Click here to learn what changesets are.

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

@vercel
Copy link
Copy Markdown
Contributor

vercel Bot commented Feb 7, 2026 •
edited
Loading

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

Project Deployment Actions Updated (UTC)
example-nextjs-workflow-turbopack Ready Ready Preview, Comment, Open in v0 Feb 10, 2026 6:54pm
example-nextjs-workflow-webpack Ready Ready Preview, Comment, Open in v0 Feb 10, 2026 6:54pm
example-workflow Ready Ready Preview, Comment, Open in v0 Feb 10, 2026 6:54pm
workbench-astro-workflow Ready Ready Preview, Comment, Open in v0 Feb 10, 2026 6:54pm
workbench-express-workflow Ready Ready Preview, Comment, Open in v0 Feb 10, 2026 6:54pm
workbench-fastify-workflow Ready Ready Preview, Comment, Open in v0 Feb 10, 2026 6:54pm
workbench-hono-workflow Ready Ready Preview, Comment, Open in v0 Feb 10, 2026 6:54pm
workbench-nitro-workflow Ready Ready Preview, Comment, Open in v0 Feb 10, 2026 6:54pm
workbench-nuxt-workflow Ready Ready Preview, Comment, Open in v0 Feb 10, 2026 6:54pm
workbench-sveltekit-workflow Ready Ready Preview, Comment, Open in v0 Feb 10, 2026 6:54pm
workbench-vite-workflow Ready Ready Preview, Comment, Open in v0 Feb 10, 2026 6:54pm
workflow-docs Ready Ready Preview, Comment, Open in v0 Feb 10, 2026 6:54pm
workflow-nest Ready Ready Preview, Comment, Open in v0 Feb 10, 2026 6:54pm
workflow-swc-playground Ready Ready Preview, Comment, Open in v0 Feb 10, 2026 6:54pm

@github-actions
Copy link
Copy Markdown
Contributor

github-actions Bot commented Feb 7, 2026 •
edited
Loading

🧪 E2E Test Results

❌ Some tests failed

Summary

Passed Failed Skipped Total
✅ ▲ Vercel Production 490 0 38 528
✅ 💻 Local Development 418 0 62 480
✅ 📦 Local Production 418 0 62 480
✅ 🐘 Local Postgres 418 0 62 480
✅ 🪟 Windows 45 0 3 48
❌ 🌍 Community Worlds 106 41 9 156
✅ 📋 Other 123 0 21 144
Total 2018 41 257 2316

❌ Failed Tests

🌍 Community Worlds (41 failed)

turso (41 failed):

  • addTenWorkflow
  • addTenWorkflow
  • should work with react rendering in step
  • promiseAllWorkflow
  • promiseRaceWorkflow
  • promiseAnyWorkflow
  • hookWorkflow
  • webhookWorkflow
  • sleepingWorkflow
  • nullByteWorkflow
  • workflowAndStepMetadataWorkflow
  • fetchWorkflow
  • promiseRaceStressTestWorkflow
  • error handling error propagation workflow errors nested function calls preserve message and stack trace
  • error handling error propagation workflow errors cross-file imports preserve message and stack trace
  • error handling error propagation step errors basic step error preserves message and stack trace
  • error handling error propagation step errors cross-file step error preserves message and function names in stack
  • error handling retry behavior regular Error retries until success
  • error handling retry behavior FatalError fails immediately without retries
  • error handling retry behavior RetryableError respects custom retryAfter delay
  • error handling retry behavior maxRetries=0 disables retries
  • error handling catchability FatalError can be caught and detected with FatalError.is()
  • hookCleanupTestWorkflow - hook token reuse after workflow completion
  • concurrent hook token conflict - two workflows cannot use the same hook token simultaneously
  • stepFunctionPassingWorkflow - step function references can be passed as arguments (without closure vars)
  • stepFunctionWithClosureWorkflow - step function with closure variables passed as argument
  • closureVariableWorkflow - nested step functions with closure variables
  • spawnWorkflowFromStepWorkflow - spawning a child workflow using start() inside a step
  • health check (queue-based) - workflow and step endpoints respond to health check messages
  • pathsAliasWorkflow - TypeScript path aliases resolve correctly
  • Calculator.calculate - static workflow method using static step methods from another class
  • AllInOneService.processNumber - static workflow method using sibling static step methods
  • ChainableService.processWithThis - static step methods using this to reference the class
  • thisSerializationWorkflow - step function invoked with .call() and .apply()
  • customSerializationWorkflow - custom class serialization with WORKFLOW_SERIALIZE/WORKFLOW_DESERIALIZE
  • instanceMethodStepWorkflow - instance methods with "use step" directive
  • crossContextSerdeWorkflow - classes defined in step code are deserializable in workflow context
  • stepFunctionAsStartArgWorkflow - step function reference passed as start() argument
  • pages router addTenWorkflow via pages router
  • pages router promiseAllWorkflow via pages router
  • pages router sleepingWorkflow via pages router

Details by Category

✅ ▲ Vercel Production
App Passed Failed Skipped
✅ astro 44 0 4
✅ example 44 0 4
✅ express 44 0 4
✅ fastify 44 0 4
✅ hono 44 0 4
✅ nextjs-turbopack 47 0 1
✅ nextjs-webpack 47 0 1
✅ nitro 44 0 4
✅ nuxt 44 0 4
✅ sveltekit 44 0 4
✅ vite 44 0 4
✅ 💻 Local Development
App Passed Failed Skipped
✅ astro-stable 41 0 7
✅ express-stable 41 0 7
✅ fastify-stable 41 0 7
✅ hono-stable 41 0 7
✅ nextjs-turbopack-stable 45 0 3
✅ nextjs-webpack-stable 45 0 3
✅ nitro-stable 41 0 7
✅ nuxt-stable 41 0 7
✅ sveltekit-stable 41 0 7
✅ vite-stable 41 0 7
✅ 📦 Local Production
App Passed Failed Skipped
✅ astro-stable 41 0 7
✅ express-stable 41 0 7
✅ fastify-stable 41 0 7
✅ hono-stable 41 0 7
✅ nextjs-turbopack-stable 45 0 3
✅ nextjs-webpack-stable 45 0 3
✅ nitro-stable 41 0 7
✅ nuxt-stable 41 0 7
✅ sveltekit-stable 41 0 7
✅ vite-stable 41 0 7
✅ 🐘 Local Postgres
App Passed Failed Skipped
✅ astro-stable 41 0 7
✅ express-stable 41 0 7
✅ fastify-stable 41 0 7
✅ hono-stable 41 0 7
✅ nextjs-turbopack-stable 45 0 3
✅ nextjs-webpack-stable 45 0 3
✅ nitro-stable 41 0 7
✅ nuxt-stable 41 0 7
✅ sveltekit-stable 41 0 7
✅ vite-stable 41 0 7
✅ 🪟 Windows
App Passed Failed Skipped
✅ nextjs-turbopack 45 0 3
❌ 🌍 Community Worlds
App Passed Failed Skipped
✅ mongodb-dev 3 0 0
✅ mongodb 45 0 3
✅ redis-dev 3 0 0
✅ redis 45 0 3
✅ starter-dev 3 0 0
✅ turso-dev 3 0 0
❌ turso 4 41 3
✅ 📋 Other
App Passed Failed Skipped
✅ e2e-local-dev-nest-stable 41 0 7
✅ e2e-local-postgres-nest-stable 41 0 7
✅ e2e-local-prod-nest-stable 41 0 7

📋 View full workflow run

@github-actions
Copy link
Copy Markdown
Contributor

github-actions Bot commented Feb 7, 2026 •
edited
Loading

📊 Benchmark Results

📈 Comparing against baseline from main branch. Green 🟢 = faster, Red 🔺 = slower.

workflow with no steps

💻 Local Development

World Framework Workflow Time Wall Time Overhead Samples vs Fastest
💻 Local 🥇 Nitro 0.033s (-11.9% 🟢) 1.006s (~) 0.973s 10 1.00x
💻 Local Express 0.034s (+5.2% 🔺) 1.005s (~) 0.971s 10 1.05x
💻 Local Next.js (Turbopack) 0.046s 1.005s 0.959s 10 1.41x
🌐 Redis Next.js (Turbopack) 0.049s 1.005s 0.956s 10 1.49x
🌐 MongoDB Next.js (Turbopack) 0.093s 1.007s 0.914s 10 2.86x
🐘 Postgres Nitro 0.136s (-57.7% 🟢) 1.009s (~) 0.873s 10 4.18x
🐘 Postgres Express 0.159s (+49.4% 🔺) 1.011s (~) 0.851s 10 4.88x
🐘 Postgres Next.js (Turbopack) 0.367s 1.009s 0.642s 10 11.25x

▲ Production (Vercel)

World Framework Workflow Time Wall Time Overhead Samples vs Fastest
▲ Vercel 🥇 Next.js (Turbopack) 0.910s (-12.8% 🟢) 2.569s (-9.1% 🟢) 1.659s 10 1.00x
▲ Vercel Nitro 0.943s (+9.1% 🔺) 2.639s (+15.2% 🔺) 1.696s 10 1.04x
▲ Vercel Express 0.959s (+15.4% 🔺) 2.736s (+16.5% 🔺) 1.776s 10 1.05x

🔍 Observability: Next.js (Turbopack) | Nitro | Express

workflow with 1 step

💻 Local Development

World Framework Workflow Time Wall Time Overhead Samples vs Fastest
🌐 Redis 🥇 Next.js (Turbopack) 1.100s 2.006s 0.906s 10 1.00x
💻 Local Nitro 1.105s (~) 2.005s (~) 0.901s 10 1.00x
💻 Local Next.js (Turbopack) 1.106s 2.005s 0.899s 10 1.01x
💻 Local Express 1.112s (~) 2.005s (~) 0.893s 10 1.01x
🌐 MongoDB Next.js (Turbopack) 1.320s 2.008s 0.688s 10 1.20x
🐘 Postgres Next.js (Turbopack) 2.095s 2.713s 0.618s 10 1.90x
🐘 Postgres Express 2.328s (-6.5% 🟢) 3.014s (~) 0.686s 10 2.12x
🐘 Postgres Nitro 2.363s (-2.6%) 3.013s (~) 0.650s 10 2.15x

▲ Production (Vercel)

World Framework Workflow Time Wall Time Overhead Samples vs Fastest
▲ Vercel 🥇 Express 2.755s (+4.1%) 4.176s (+8.4% 🔺) 1.421s 10 1.00x
▲ Vercel Nitro 2.805s (+1.7%) 3.921s (+4.9%) 1.115s 10 1.02x
▲ Vercel Next.js (Turbopack) 2.817s (~) 4.149s (+3.1%) 1.332s 10 1.02x

🔍 Observability: Express | Nitro | Next.js (Turbopack)

workflow with 10 sequential steps

💻 Local Development

World Framework Workflow Time Wall Time Overhead Samples vs Fastest
🌐 Redis 🥇 Next.js (Turbopack) 10.707s 11.023s 0.316s 3 1.00x
💻 Local Next.js (Turbopack) 10.749s 11.023s 0.274s 3 1.00x
💻 Local Nitro 10.831s (~) 11.022s (~) 0.191s 3 1.01x
💻 Local Express 10.875s (~) 11.024s (~) 0.149s 3 1.02x
🌐 MongoDB Next.js (Turbopack) 12.278s 13.021s 0.743s 3 1.15x
🐘 Postgres Next.js (Turbopack) 15.382s 16.043s 0.661s 2 1.44x
🐘 Postgres Nitro 20.372s (~) 21.056s (~) 0.684s 2 1.90x
🐘 Postgres Express 20.416s (~) 21.056s (~) 0.640s 2 1.91x

▲ Production (Vercel)

World Framework Workflow Time Wall Time Overhead Samples vs Fastest
▲ Vercel 🥇 Next.js (Turbopack) 20.990s (+6.8% 🔺) 22.238s (+5.5% 🔺) 1.248s 2 1.00x
▲ Vercel Nitro 21.200s (+6.3% 🔺) 22.482s (+7.9% 🔺) 1.282s 2 1.01x
▲ Vercel Express 21.593s (+10.1% 🔺) 23.061s (+7.8% 🔺) 1.467s 2 1.03x

🔍 Observability: Next.js (Turbopack) | Nitro | Express

workflow with 25 sequential steps

💻 Local Development

World Framework Workflow Time Wall Time Overhead Samples vs Fastest
🌐 Redis 🥇 Next.js (Turbopack) 26.897s 27.051s 0.154s 3 1.00x
💻 Local Next.js (Turbopack) 27.222s 28.054s 0.833s 3 1.01x
💻 Local Nitro 27.441s (~) 28.052s (~) 0.611s 3 1.02x
💻 Local Express 27.617s (~) 28.054s (~) 0.437s 3 1.03x
🌐 MongoDB Next.js (Turbopack) 30.499s 31.040s 0.541s 2 1.13x
🐘 Postgres Nitro 38.181s (-24.1% 🟢) 38.592s (-24.5% 🟢) 0.411s 2 1.42x
🐘 Postgres Next.js (Turbopack) 41.733s 42.105s 0.372s 2 1.55x
🐘 Postgres Express 50.181s (~) 51.129s (+1.0%) 0.948s 2 1.87x

▲ Production (Vercel)

World Framework Workflow Time Wall Time Overhead Samples vs Fastest
▲ Vercel 🥇 Next.js (Turbopack) 55.943s (+10.2% 🔺) 56.818s (+8.5% 🔺) 0.875s 2 1.00x
▲ Vercel Nitro 58.693s (+14.5% 🔺) 60.851s (+15.8% 🔺) 2.158s 1 1.05x
▲ Vercel Express 59.361s (+21.8% 🔺) 60.562s (+21.8% 🔺) 1.201s 1 1.06x

🔍 Observability: Next.js (Turbopack) | Nitro | Express

workflow with 50 sequential steps

💻 Local Development

World Framework Workflow Time Wall Time Overhead Samples vs Fastest
🌐 Redis 🥇 Next.js (Turbopack) 54.388s 55.098s 0.711s 2 1.00x
💻 Local Next.js (Turbopack) 56.733s 57.105s 0.372s 2 1.04x
💻 Local Nitro 57.111s (~) 57.601s (+0.9%) 0.490s 2 1.05x
💻 Local Express 57.432s (+0.5%) 58.106s (~) 0.673s 2 1.06x
🌐 MongoDB Next.js (Turbopack) 61.467s 62.084s 0.617s 2 1.13x
🐘 Postgres Nitro 75.350s (-24.8% 🟢) 76.169s (-24.0% 🟢) 0.819s 2 1.39x
🐘 Postgres Next.js (Turbopack) 100.193s 100.232s 0.039s 1 1.84x
🐘 Postgres Express 100.327s (+33.2% 🔺) 101.242s (+32.9% 🔺) 0.915s 1 1.84x

▲ Production (Vercel)

World Framework Workflow Time Wall Time Overhead Samples vs Fastest
▲ Vercel 🥇 Nitro 115.101s (+11.6% 🔺) 116.281s (+11.0% 🔺) 1.180s 1 1.00x
▲ Vercel Express 115.237s (+9.2% 🔺) 117.235s (+9.9% 🔺) 1.998s 1 1.00x
▲ Vercel Next.js (Turbopack) 118.912s (+9.6% 🔺) 119.670s (+8.2% 🔺) 0.758s 1 1.03x

🔍 Observability: Nitro | Express | Next.js (Turbopack)

Promise.all with 10 concurrent steps

💻 Local Development

World Framework Workflow Time Wall Time Overhead Samples vs Fastest
🌐 Redis 🥇 Next.js (Turbopack) 1.273s 2.006s 0.733s 15 1.00x
💻 Local Next.js (Turbopack) 1.396s 2.005s 0.610s 15 1.10x
💻 Local Nitro 1.400s (~) 2.005s (~) 0.605s 15 1.10x
💻 Local Express 1.412s (+1.2%) 2.006s (~) 0.594s 15 1.11x
🌐 MongoDB Next.js (Turbopack) 2.167s 3.009s 0.842s 10 1.70x
🐘 Postgres Next.js (Turbopack) 2.312s 3.013s 0.702s 10 1.82x
🐘 Postgres Express 2.363s (+20.3% 🔺) 3.013s (+31.2% 🔺) 0.650s 10 1.86x
🐘 Postgres Nitro 2.375s (+4.5%) 2.921s (-3.1%) 0.546s 11 1.87x

▲ Production (Vercel)

World Framework Workflow Time Wall Time Overhead Samples vs Fastest
▲ Vercel 🥇 Express 3.358s (+19.0% 🔺) 4.902s (+26.6% 🔺) 1.544s 7 1.00x
▲ Vercel Nitro 3.375s (+11.6% 🔺) 4.896s (+15.2% 🔺) 1.521s 7 1.01x
▲ Vercel Next.js (Turbopack) 4.960s (+50.1% 🔺) 6.334s (+35.8% 🔺) 1.373s 5 1.48x

🔍 Observability: Express | Nitro | Next.js (Turbopack)

Promise.all with 25 concurrent steps

💻 Local Development

World Framework Workflow Time Wall Time Overhead Samples vs Fastest
💻 Local 🥇 Next.js (Turbopack) 2.439s 3.009s 0.569s 10 1.00x
🌐 Redis Next.js (Turbopack) 2.485s 3.008s 0.523s 10 1.02x
💻 Local Nitro 2.566s (+3.2%) 3.007s (~) 0.442s 10 1.05x
💻 Local Express 2.611s (+4.2%) 3.009s (~) 0.398s 10 1.07x
🌐 MongoDB Next.js (Turbopack) 4.784s 5.179s 0.395s 6 1.96x
🐘 Postgres Nitro 8.777s (-2.0%) 9.280s (-2.7%) 0.502s 4 3.60x
🐘 Postgres Express 9.033s (-9.1% 🟢) 9.528s (-7.3% 🟢) 0.495s 4 3.70x
🐘 Postgres Next.js (Turbopack) 11.976s 12.370s 0.394s 3 4.91x

▲ Production (Vercel)

World Framework Workflow Time Wall Time Overhead Samples vs Fastest
▲ Vercel 🥇 Express 4.035s (+10.6% 🔺) 6.061s (+27.6% 🔺) 2.026s 5 1.00x
▲ Vercel Next.js (Turbopack) 6.049s (+76.9% 🔺) 7.180s (+45.8% 🔺) 1.131s 5 1.50x
▲ Vercel Nitro 11.916s (-23.0% 🟢) 13.328s (-19.4% 🟢) 1.413s 5 2.95x

🔍 Observability: Express | Next.js (Turbopack) | Nitro

Promise.all with 50 concurrent steps

💻 Local Development

World Framework Workflow Time Wall Time Overhead Samples vs Fastest
🌐 Redis 🥇 Next.js (Turbopack) 4.047s 4.582s 0.535s 7 1.00x
💻 Local Nitro 7.150s (+2.5%) 8.023s (+6.7% 🔺) 0.873s 4 1.77x
💻 Local Next.js (Turbopack) 7.273s 7.766s 0.493s 4 1.80x
💻 Local Express 7.335s (+1.2%) 8.020s (~) 0.685s 4 1.81x
🌐 MongoDB Next.js (Turbopack) 9.922s 10.351s 0.429s 3 2.45x
🐘 Postgres Express 49.130s (-4.4%) 50.130s (-3.8%) 1.000s 1 12.14x
🐘 Postgres Nitro 51.672s (+12.7% 🔺) 52.142s (+13.0% 🔺) 0.470s 1 12.77x
🐘 Postgres Next.js (Turbopack) 53.529s 54.133s 0.604s 1 13.23x

▲ Production (Vercel)

World Framework Workflow Time Wall Time Overhead Samples vs Fastest
▲ Vercel 🥇 Nitro 5.102s (+55.6% 🔺) 6.417s (+48.8% 🔺) 1.315s 5 1.00x
▲ Vercel Next.js (Turbopack) 5.971s (+32.8% 🔺) 7.046s (+11.6% 🔺) 1.075s 5 1.17x
▲ Vercel Express 6.645s (+64.8% 🔺) 8.284s (+48.9% 🔺) 1.639s 4 1.30x

🔍 Observability: Nitro | Next.js (Turbopack) | Express

Promise.race with 10 concurrent steps

💻 Local Development

World Framework Workflow Time Wall Time Overhead Samples vs Fastest
🌐 Redis 🥇 Next.js (Turbopack) 1.274s 2.006s 0.732s 15 1.00x
💻 Local Next.js (Turbopack) 1.417s 2.005s 0.588s 15 1.11x
💻 Local Nitro 1.424s (-1.4%) 2.005s (~) 0.581s 15 1.12x
💻 Local Express 1.437s (+0.7%) 2.005s (~) 0.568s 15 1.13x
🐘 Postgres Nitro 2.081s (-5.5% 🟢) 2.833s (+12.8% 🔺) 0.752s 11 1.63x
🐘 Postgres Express 2.104s (-1.6%) 2.831s (+12.7% 🔺) 0.726s 11 1.65x
🐘 Postgres Next.js (Turbopack) 2.146s 2.743s 0.597s 11 1.68x
🌐 MongoDB Next.js (Turbopack) 2.147s 3.008s 0.861s 10 1.68x

▲ Production (Vercel)

World Framework Workflow Time Wall Time Overhead Samples vs Fastest
▲ Vercel 🥇 Next.js (Turbopack) 3.288s (+2.7%) 5.009s (+15.8% 🔺) 1.721s 6 1.00x
▲ Vercel Express 5.551s (+74.2% 🔺) 7.000s (+50.4% 🔺) 1.449s 5 1.69x
▲ Vercel Nitro 6.537s (+104.4% 🔺) 8.017s (+79.6% 🔺) 1.480s 4 1.99x

🔍 Observability: Next.js (Turbopack) | Express | Nitro

Promise.race with 25 concurrent steps

💻 Local Development

World Framework Workflow Time Wall Time Overhead Samples vs Fastest
🌐 Redis 🥇 Next.js (Turbopack) 2.498s 3.008s 0.509s 10 1.00x
💻 Local Nitro 2.662s (+0.9%) 3.007s (~) 0.346s 10 1.07x
💻 Local Next.js (Turbopack) 2.727s 3.110s 0.384s 10 1.09x
💻 Local Express 2.742s (+3.1%) 3.008s (~) 0.266s 10 1.10x
🌐 MongoDB Next.js (Turbopack) 4.785s 5.177s 0.392s 6 1.92x
🐘 Postgres Express 10.405s (-7.5% 🟢) 11.032s (-5.7% 🟢) 0.627s 3 4.16x
🐘 Postgres Nitro 10.466s (-13.4% 🟢) 11.029s (-10.8% 🟢) 0.563s 3 4.19x
🐘 Postgres Next.js (Turbopack) 12.867s 13.369s 0.502s 3 5.15x

▲ Production (Vercel)

World Framework Workflow Time Wall Time Overhead Samples vs Fastest
▲ Vercel 🥇 Nitro 3.120s (+2.1%) 4.434s (+3.3%) 1.314s 7 1.00x
▲ Vercel Next.js (Turbopack) 3.188s (-2.3%) 4.402s (-1.6%) 1.213s 7 1.02x
▲ Vercel Express 4.371s (+42.1% 🔺) 6.065s (+40.4% 🔺) 1.695s 5 1.40x

🔍 Observability: Nitro | Next.js (Turbopack) | Express

Promise.race with 50 concurrent steps

💻 Local Development

World Framework Workflow Time Wall Time Overhead Samples vs Fastest
🌐 Redis 🥇 Next.js (Turbopack) 4.081s 4.726s 0.645s 7 1.00x
💻 Local Nitro 7.864s (+2.4%) 8.019s (~) 0.155s 4 1.93x
💻 Local Next.js (Turbopack) 8.450s 9.021s 0.571s 4 2.07x
💻 Local Express 8.467s (+10.3% 🔺) 9.025s (+12.6% 🔺) 0.558s 4 2.07x
🌐 MongoDB Next.js (Turbopack) 9.945s 10.686s 0.741s 3 2.44x
🐘 Postgres Nitro 51.506s (+1.7%) 52.117s (+1.9%) 0.611s 1 12.62x
🐘 Postgres Next.js (Turbopack) 51.819s 52.123s 0.304s 1 12.70x
🐘 Postgres Express 52.330s (~) 53.118s (~) 0.788s 1 12.82x

▲ Production (Vercel)

World Framework Workflow Time Wall Time Overhead Samples vs Fastest
▲ Vercel 🥇 Express 3.906s (+12.3% 🔺) 5.790s (+18.9% 🔺) 1.884s 6 1.00x
▲ Vercel Nitro 4.247s (-2.4%) 5.769s (~) 1.521s 6 1.09x
▲ Vercel Next.js (Turbopack) 5.724s (+54.5% 🔺) 7.023s (+39.4% 🔺) 1.298s 5 1.47x

🔍 Observability: Express | Nitro | Next.js (Turbopack)

Stream Benchmarks (includes TTFB metrics)
workflow with stream

💻 Local Development

World Framework Workflow Time TTFB Slurp Wall Time Overhead Samples vs Fastest
🌐 Redis 🥇 Next.js (Turbopack) 0.143s 1.000s 0.001s 1.007s 0.864s 10 1.00x
💻 Local Next.js (Turbopack) 0.155s 1.000s 0.010s 1.014s 0.859s 10 1.08x
💻 Local Nitro 0.172s (+2.8%) 1.003s (~) 0.010s (+1.0%) 1.015s (~) 0.843s 10 1.20x
💻 Local Express 0.180s (+4.2%) 1.003s (~) 0.010s (-3.8%) 1.016s (~) 0.836s 10 1.26x
🌐 MongoDB Next.js (Turbopack) 0.506s 0.945s 0.001s 1.009s 0.503s 10 3.53x
🐘 Postgres Next.js (Turbopack) 1.321s 1.723s 0.001s 2.012s 0.691s 10 9.22x
🐘 Postgres Nitro 1.401s (-39.9% 🟢) 1.639s (-39.5% 🟢) 0.001s (~) 2.013s (-33.2% 🟢) 0.612s 10 9.78x
🐘 Postgres Express 2.434s (+67.3% 🔺) 2.607s (+56.8% 🔺) 0.001s (~) 3.013s (+49.8% 🔺) 0.579s 10 17.00x

▲ Production (Vercel)

World Framework Workflow Time TTFB Slurp Wall Time Overhead Samples vs Fastest
▲ Vercel 🥇 Next.js (Turbopack) 3.106s (+15.8% 🔺) 3.562s (+9.4% 🔺) 0.297s (+11.5% 🔺) 4.689s (+8.1% 🔺) 1.582s 10 1.00x
▲ Vercel Nitro 3.368s (+27.1% 🔺) 4.238s (+36.8% 🔺) 0.290s (+72.7% 🔺) 5.515s (+35.3% 🔺) 2.147s 10 1.08x
▲ Vercel Express 3.522s (+15.4% 🔺) 4.198s (+16.3% 🔺) 0.311s (+95.0% 🔺) 5.505s (+22.9% 🔺) 1.983s 10 1.13x

🔍 Observability: Next.js (Turbopack) | Nitro | Express

Summary

Fastest Framework by World

Winner determined by most benchmark wins

World 🥇 Fastest Framework Wins
💻 Local Next.js (Turbopack) 7/12
🐘 Postgres Nitro 6/12
▲ Vercel Next.js (Turbopack) 5/12
Fastest World by Framework

Winner determined by most benchmark wins

Framework 🥇 Fastest World Wins
Express 💻 Local 10/12
Next.js (Turbopack) 🌐 Redis 10/12
Nitro 💻 Local 10/12
Column Definitions
  • Workflow Time: Runtime reported by workflow (completedAt - createdAt) - primary metric
  • TTFB: Time to First Byte - time from workflow start until first stream byte received (stream benchmarks only)
  • Slurp: Time from first byte to complete stream consumption (stream benchmarks only)
  • Wall Time: Total testbench time (trigger workflow + poll for result)
  • Overhead: Testbench overhead (Wall Time - Workflow Time)
  • Samples: Number of benchmark iterations run
  • vs Fastest: How much slower compared to the fastest configuration for this benchmark

Worlds:

  • 💻 Local: In-memory filesystem world (local development)
  • 🐘 Postgres: PostgreSQL database world (local development)
  • ▲ Vercel: Vercel production/preview deployment
  • 🌐 Starter: Community world (local development)
  • 🌐 Turso: Community world (local development)
  • 🌐 MongoDB: Community world (local development)
  • 🌐 Redis: Community world (local development)
  • 🌐 Jazz: Community world (local development)

📋 View full workflow run

@ijjk ijjk force-pushed the ijjk/lazy-deferred-entries branch from c2f801c to 569c87b Compare February 7, 2026 21:24
pranaygp
pranaygp reviewed Feb 9, 2026
View reviewed changes
Copy link
Copy Markdown
Contributor

@pranaygp pranaygp left a comment

Choose a reason for hiding this comment

The reason will be displayed to describe this comment to others. Learn more.

Review: Add lazy workflow/step discovery via deferredEntries in next (#976)

This PR splits the existing NextBuilder into two strategies:

  • Eager builder (builder-eager.ts): The original pre-discovery approach (watchpack-based file watching)
  • Deferred builder (builder-deferred.ts): New lazy discovery via Next.js deferredEntries experimental API + TCP socket communication between loader and builder

The version gate is 16.2.0-canary.30. Overall the architecture is sound - the socket-based discovery channel is well-authenticated and the deferred build queue properly serializes concurrent invocations. Several observations and questions below.

Architecture Observations

  1. Builder refactoring is clean: The eager builder is a direct extract of the original code. The deferred builder introduces a fundamentally different lifecycle where build() only writes stubs and starts the socket server, and actual compilation happens lazily via onBeforeDeferredEntries().

  2. Socket security is reasonable: localhost-only binding + random auth token + message preamble is adequate for local IPC.

  3. Build signature deduplication is smart: Using file size + mtime hash to avoid redundant builds is a good optimization.

Issues & Questions

See inline comments for specifics.

Comment thread packages/next/src/builder-deferred.ts
Comment thread packages/next/src/builder-deferred.ts
Comment thread packages/next/src/loader.ts
Comment thread packages/next/src/socket-server.ts
Comment thread packages/next/src/loader.ts
Comment thread packages/next/package.json
Comment thread packages/next/src/index.ts
@vercel-release-bot vercel-release-bot mentioned this pull request Feb 10, 2026
Merged
Sign up for free to join this conversation on GitHub. Already have an account? Sign in to comment

Reviewers

@TooTallNate TooTallNate TooTallNate approved these changes

@pranaygp pranaygp Awaiting requested review from pranaygp

Assignees

No one assigned

Labels

None yet

Projects

None yet

Milestone

No milestone

Development

Successfully merging this pull request may close these issues.

3 participants

@ijjk @TooTallNate @pranaygp