Enable custom class serialization transformations for "client" mode

[TooTallNate]

Enable class serialization in client mode to support passing class instances to workflow functions.

What changed?

• Added support for class serialization transformations in "client" mode
• The plugin now generates necessary imports and registration calls for classes that need serialization in client mode
• When classes are detected that need serialization, the plugin:
  • Imports registerSerializationClass from "workflow/internal/class-serialization"
  • Adds registration calls for each class with a unique class ID
• Updated test outputs to reflect these changes

How to test?

1. Create a class with serialization methods (using WORKFLOW_SERIALIZE and WORKFLOW_DESERIALIZE symbols)
2. Use the class in a client-side context where it's passed to a workflow function
3. Verify that the class is properly serialized and deserialized when passed between client and workflow

Why make this change?

Previously, class serialization was only enabled in workflow mode, which meant that classes couldn't be properly serialized when passed from client code to workflow functions. This change ensures that classes with custom serialization methods work correctly when used as arguments to start(workflow) calls from client code.

[changeset-bot]

🦋 Changeset detected

Latest commit: 1a72c70

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

This PR includes changesets to release 15 packages

Name	Type
@workflow/swc-plugin	Patch
@workflow/astro	Patch
@workflow/builders	Patch
@workflow/cli	Patch
@workflow/nest	Patch
@workflow/next	Patch
@workflow/nitro	Patch
@workflow/rollup	Patch
@workflow/sveltekit	Patch
workflow	Patch
@workflow/world-testing	Patch
@workflow/example-nest	Patch
@workflow/docs-typecheck	Patch
@workflow/nuxt	Patch
@workflow/ai	Patch

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

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

[github-actions]

🧪 E2E Test Results

❌ Some tests failed

Summary

	Passed	Failed	Skipped	Total
✅ ▲ Vercel Production	457	0	38	495
❌ 💻 Local Development	416	2	32	450
✅ 📦 Local Production	418	0	32	450
✅ 🐘 Local Postgres	418	0	32	450
✅ 🪟 Windows	45	0	0	45
❌ 🌍 Community Worlds	31	161	0	192
✅ 📋 Other	123	0	12	135
Total	1908	163	146	2217

❌ Failed Tests

💻 Local Development (2 failed)

astro-stable (2 failed):

• 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

🌍 Community Worlds (161 failed)

mongodb (40 failed):

• addTenWorkflow
• addTenWorkflow
• should work with react rendering in step
• promiseAllWorkflow
• promiseRaceWorkflow
• promiseAnyWorkflow
• readableStreamWorkflow
• hookWorkflow
• webhookWorkflow
• sleepingWorkflow
• nullByteWorkflow
• workflowAndStepMetadataWorkflow
• outputStreamWorkflow
• outputStreamInsideStepWorkflow - getWritable() called inside step functions
• 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
• 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
• pages router addTenWorkflow via pages router
• pages router promiseAllWorkflow via pages router
• pages router sleepingWorkflow via pages router

redis (40 failed):

• addTenWorkflow
• addTenWorkflow
• should work with react rendering in step
• promiseAllWorkflow
• promiseRaceWorkflow
• promiseAnyWorkflow
• readableStreamWorkflow
• hookWorkflow
• webhookWorkflow
• sleepingWorkflow
• nullByteWorkflow
• workflowAndStepMetadataWorkflow
• outputStreamWorkflow
• outputStreamInsideStepWorkflow - getWritable() called inside step functions
• 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
• 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
• pages router addTenWorkflow via pages router
• pages router promiseAllWorkflow via pages router
• pages router sleepingWorkflow via pages router

starter (41 failed):

• addTenWorkflow
• addTenWorkflow
• should work with react rendering in step
• promiseAllWorkflow
• promiseRaceWorkflow
• promiseAnyWorkflow
• readableStreamWorkflow
• hookWorkflow
• webhookWorkflow
• sleepingWorkflow
• nullByteWorkflow
• workflowAndStepMetadataWorkflow
• outputStreamWorkflow
• outputStreamInsideStepWorkflow - getWritable() called inside step functions
• 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 (CLI) - workflow health command reports healthy endpoints
• 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
• pages router addTenWorkflow via pages router
• pages router promiseAllWorkflow via pages router
• pages router sleepingWorkflow via pages router

turso (40 failed):

• addTenWorkflow
• addTenWorkflow
• should work with react rendering in step
• promiseAllWorkflow
• promiseRaceWorkflow
• promiseAnyWorkflow
• readableStreamWorkflow
• hookWorkflow
• webhookWorkflow
• sleepingWorkflow
• nullByteWorkflow
• workflowAndStepMetadataWorkflow
• outputStreamWorkflow
• outputStreamInsideStepWorkflow - getWritable() called inside step functions
• 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
• 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
• 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	41	0	4
✅ example	41	0	4
✅ express	41	0	4
✅ fastify	41	0	4
✅ hono	41	0	4
✅ nextjs-turbopack	44	0	1
✅ nextjs-webpack	44	0	1
✅ nitro	41	0	4
✅ nuxt	41	0	4
✅ sveltekit	41	0	4
✅ vite	41	0	4

❌ 💻 Local Development

App	Passed	Failed	Skipped
❌ astro-stable	39	2	4
✅ express-stable	41	0	4
✅ fastify-stable	41	0	4
✅ hono-stable	41	0	4
✅ nextjs-turbopack-stable	45	0	0
✅ nextjs-webpack-stable	45	0	0
✅ nitro-stable	41	0	4
✅ nuxt-stable	41	0	4
✅ sveltekit-stable	41	0	4
✅ vite-stable	41	0	4

✅ 📦 Local Production

App	Passed	Failed	Skipped
✅ astro-stable	41	0	4
✅ express-stable	41	0	4
✅ fastify-stable	41	0	4
✅ hono-stable	41	0	4
✅ nextjs-turbopack-stable	45	0	0
✅ nextjs-webpack-stable	45	0	0
✅ nitro-stable	41	0	4
✅ nuxt-stable	41	0	4
✅ sveltekit-stable	41	0	4
✅ vite-stable	41	0	4

✅ 🐘 Local Postgres

App	Passed	Failed	Skipped
✅ astro-stable	41	0	4
✅ express-stable	41	0	4
✅ fastify-stable	41	0	4
✅ hono-stable	41	0	4
✅ nextjs-turbopack-stable	45	0	0
✅ nextjs-webpack-stable	45	0	0
✅ nitro-stable	41	0	4
✅ nuxt-stable	41	0	4
✅ sveltekit-stable	41	0	4
✅ vite-stable	41	0	4

✅ 🪟 Windows

App	Passed	Failed	Skipped
✅ nextjs-turbopack	45	0	0

❌ 🌍 Community Worlds

App	Passed	Failed	Skipped
✅ mongodb-dev	3	0	0
❌ mongodb	5	40	0
✅ redis-dev	3	0	0
❌ redis	5	40	0
✅ starter-dev	3	0	0
❌ starter	4	41	0
✅ turso-dev	3	0	0
❌ turso	5	40	0

✅ 📋 Other

App	Passed	Failed	Skipped
✅ e2e-local-dev-nest-stable	41	0	4
✅ e2e-local-postgres-nest-stable	41	0	4
✅ e2e-local-prod-nest-stable	41	0	4

---

📋 View full workflow run

---

❌ Some E2E test jobs failed:

• Vercel Prod: success
• Local Dev: failure
• Local Prod: success
• Local Postgres: success
• Windows: success

Check the workflow run for details.

[vercel]

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

Project	Deployment	Review	Updated (UTC)
example-nextjs-workflow-turbopack	Ready	Preview, Comment	Jan 27, 2026 7:00am
example-nextjs-workflow-webpack	Ready	Preview, Comment	Jan 27, 2026 7:00am
example-workflow	Ready	Preview, Comment	Jan 27, 2026 7:00am
workbench-astro-workflow	Ready	Preview, Comment	Jan 27, 2026 7:00am
workbench-express-workflow	Ready	Preview, Comment	Jan 27, 2026 7:00am
workbench-fastify-workflow	Ready	Preview, Comment	Jan 27, 2026 7:00am
workbench-hono-workflow	Ready	Preview, Comment	Jan 27, 2026 7:00am
workbench-nitro-workflow	Ready	Preview, Comment	Jan 27, 2026 7:00am
workbench-nuxt-workflow	Ready	Preview, Comment	Jan 27, 2026 7:00am
workbench-sveltekit-workflow	Ready	Preview, Comment	Jan 27, 2026 7:00am
workbench-vite-workflow	Ready	Preview, Comment	Jan 27, 2026 7:00am
workflow-docs	Ready	Preview, Comment	Jan 27, 2026 7:00am
workflow-nest	Error		Jan 27, 2026 7:00am

[TooTallNate]

• Enable custom class serialization transformations for "client" mode #860 👈 (View in Graphite)
• main

This stack of pull requests is managed by Graphite. Learn more about stacking.

[Copilot]

Pull request overview

This PR enables custom class serialization transformations for "client" mode in the SWC plugin. Previously, class serialization was only handled in workflow and step modes. This change ensures that classes with custom serialization methods can be properly serialized when passed from client code to workflow functions via start(workflow) calls.

Changes:

• Added import generation for registerSerializationClass in client mode when classes need serialization
• Added registration call generation for classes in client mode (both Module and Script cases)
• Updated test fixtures to reflect the new client mode behavior with serialization imports and registration calls

Reviewed changes

Copilot reviewed 7 out of 7 changed files in this pull request and generated 3 comments.

Show a summary per file

File	Description
packages/swc-plugin-workflow/transform/src/lib.rs	Added logic to generate serialization imports and registration calls for client mode in both Module and Script cases
packages/swc-plugin-workflow/transform/tests/fixture/static-method-step/output-client.js	Added expected import and registration call for MyService class
packages/swc-plugin-workflow/transform/tests/fixture/custom-serialization/output-client.js	Added expected import and registration call for Point class
packages/swc-plugin-workflow/transform/tests/fixture/custom-serialization-local-const/output-client.js	Added expected import and registration calls for Circle, Rectangle, and Triangle classes
packages/swc-plugin-workflow/transform/tests/fixture/custom-serialization-imported/output-client.js	Added expected import and registration calls for Color and Vector classes
packages/swc-plugin-workflow/transform/tests/errors/instance-methods/output-client.js	Added expected import and registration call for TestClass
.changeset/modern-clubs-own.md	Added changeset documenting this patch change

---

💡 Add Copilot custom instructions for smarter, more guided reviews. Learn how to get started.

[ijjk]

Seems good but the deduplication callout from copilot does seem good as well

[github-actions]

📊 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	🥇 Next.js (Turbopack)	0.041s (-16.4% 🟢)	1.019s (~)	0.978s	10	1.00x
💻 Local	Express	0.043s (-1.6%)	1.008s (-1.3%)	0.965s	10	1.04x
💻 Local	Nitro	0.043s (-11.1% 🟢)	1.007s (~)	0.964s	10	1.06x
🐘 Postgres	Express	0.127s (-48.6% 🟢)	1.015s (~)	0.888s	10	3.10x
🐘 Postgres	Nitro	0.162s (-60.9% 🟢)	1.026s (+1.2%)	0.864s	10	3.96x
🐘 Postgres	Next.js (Turbopack)	0.242s (+100.4% 🔺)	1.021s (~)	0.778s	10	5.93x

▲ Production (Vercel)

World	Framework	Workflow Time	Wall Time	Overhead	Samples	vs Fastest
▲ Vercel	🥇 Nitro	0.596s (-11.7% 🟢)	1.698s (+12.3% 🔺)	1.101s	10	1.00x
▲ Vercel	Express	0.629s (-18.0% 🟢)	1.601s (-5.4% 🟢)	0.972s	10	1.05x
▲ Vercel	Next.js (Turbopack)	0.695s (-17.4% 🟢)	1.553s (-9.9% 🟢)	0.858s	10	1.17x

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

workflow with 1 step

💻 Local Development

World	Framework	Workflow Time	Wall Time	Overhead	Samples	vs Fastest
💻 Local	🥇 Next.js (Turbopack)	1.103s (~)	2.012s (~)	0.909s	10	1.00x
💻 Local	Express	1.116s (~)	2.008s (~)	0.892s	10	1.01x
💻 Local	Nitro	1.118s (~)	2.007s (~)	0.889s	10	1.01x
🐘 Postgres	Next.js (Turbopack)	2.254s (+17.5% 🔺)	3.019s (+49.8% 🔺)	0.765s	10	2.04x
🐘 Postgres	Express	2.472s (+17.8% 🔺)	3.013s (~)	0.541s	10	2.24x
🐘 Postgres	Nitro	2.473s (+9.2% 🔺)	3.014s (~)	0.542s	10	2.24x

▲ Production (Vercel)

World	Framework	Workflow Time	Wall Time	Overhead	Samples	vs Fastest
▲ Vercel	🥇 Express	2.730s (-1.8%)	3.744s (+3.0%)	1.013s	10	1.00x
▲ Vercel	Nitro	2.874s (~)	3.779s (+4.6%)	0.905s	10	1.05x
▲ Vercel	Next.js (Turbopack)	2.952s (+1.5%)	3.663s (-0.7%)	0.711s	10	1.08x

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

workflow with 10 sequential steps

💻 Local Development

World	Framework	Workflow Time	Wall Time	Overhead	Samples	vs Fastest
💻 Local	🥇 Next.js (Turbopack)	10.716s (~)	11.018s (~)	0.302s	5	1.00x
💻 Local	Nitro	10.841s (~)	11.014s (~)	0.173s	5	1.01x
💻 Local	Express	10.852s (~)	11.013s (~)	0.161s	5	1.01x
🐘 Postgres	Nitro	20.292s (+0.6%)	21.041s (~)	0.750s	5	1.89x
🐘 Postgres	Express	20.310s (+30.5% 🔺)	21.037s (+31.2% 🔺)	0.726s	5	1.90x
🐘 Postgres	Next.js (Turbopack)	20.354s (+40.4% 🔺)	21.043s (+39.9% 🔺)	0.689s	5	1.90x

▲ Production (Vercel)

World	Framework	Workflow Time	Wall Time	Overhead	Samples	vs Fastest
▲ Vercel	🥇 Nitro	22.236s (-6.6% 🟢)	23.066s (-5.8% 🟢)	0.830s	5	1.00x
▲ Vercel	Express	22.515s (-6.9% 🟢)	23.414s (-6.1% 🟢)	0.898s	5	1.01x
▲ Vercel	Next.js (Turbopack)	22.838s (~)	23.452s (-1.4%)	0.614s	5	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
💻 Local	🥇 Next.js (Turbopack)	1.389s (~)	2.012s (~)	0.622s	15	1.00x
💻 Local	Nitro	1.413s (~)	2.007s (~)	0.594s	15	1.02x
💻 Local	Express	1.414s (-0.8%)	2.007s (~)	0.593s	15	1.02x
🐘 Postgres	Next.js (Turbopack)	2.200s (+3.3%)	2.853s (+5.3% 🔺)	0.653s	11	1.58x
🐘 Postgres	Nitro	2.305s (-4.9%)	2.678s (-11.0% 🟢)	0.373s	12	1.66x
🐘 Postgres	Express	2.515s (+21.3% 🔺)	3.014s (+16.0% 🔺)	0.499s	10	1.81x

▲ Production (Vercel)

World	Framework	Workflow Time	Wall Time	Overhead	Samples	vs Fastest
▲ Vercel	🥇 Next.js (Turbopack)	3.000s (-3.5%)	3.773s (-5.5% 🟢)	0.773s	8	1.00x
▲ Vercel	Nitro	3.406s (+7.1% 🔺)	4.360s (+11.9% 🔺)	0.954s	7	1.14x
▲ Vercel	Express	3.551s (+21.7% 🔺)	4.414s (+16.5% 🔺)	0.863s	7	1.18x

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

Promise.all with 25 concurrent steps

💻 Local Development

World	Framework	Workflow Time	Wall Time	Overhead	Samples	vs Fastest
💻 Local	🥇 Next.js (Turbopack)	2.472s (~)	3.066s (-4.3%)	0.594s	10	1.00x
💻 Local	Express	2.502s (-2.0%)	3.029s (+0.5%)	0.527s	10	1.01x
💻 Local	Nitro	2.510s (-2.1%)	3.026s (~)	0.515s	10	1.02x
🐘 Postgres	Express	7.934s (-20.5% 🟢)	8.305s (-20.5% 🟢)	0.371s	4	3.21x
🐘 Postgres	Nitro	8.839s (+18.5% 🔺)	9.274s (+14.9% 🔺)	0.435s	4	3.58x
🐘 Postgres	Next.js (Turbopack)	11.559s (-0.8%)	12.037s (-0.7%)	0.478s	3	4.68x

▲ Production (Vercel)

World	Framework	Workflow Time	Wall Time	Overhead	Samples	vs Fastest
▲ Vercel	🥇 Next.js (Turbopack)	3.235s (-6.5% 🟢)	4.052s (-0.7%)	0.817s	8	1.00x
▲ Vercel	Express	3.374s (+2.4%)	4.168s (+2.8%)	0.795s	8	1.04x
▲ Vercel	Nitro	3.535s (+15.7% 🔺)	4.228s (+10.6% 🔺)	0.694s	8	1.09x

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

Promise.race with 10 concurrent steps

💻 Local Development

World	Framework	Workflow Time	Wall Time	Overhead	Samples	vs Fastest
💻 Local	🥇 Nitro	1.409s (-2.7%)	2.007s (~)	0.598s	15	1.00x
💻 Local	Next.js (Turbopack)	1.427s (+1.0%)	2.013s (~)	0.586s	15	1.01x
💻 Local	Express	1.434s (~)	2.006s (~)	0.572s	15	1.02x
🐘 Postgres	Nitro	1.967s (-8.0% 🟢)	2.477s (-4.7%)	0.511s	13	1.40x
🐘 Postgres	Express	2.061s (+14.5% 🔺)	2.528s (+13.3% 🔺)	0.467s	12	1.46x
🐘 Postgres	Next.js (Turbopack)	2.299s (-2.5%)	2.746s (-9.2% 🟢)	0.447s	11	1.63x

▲ Production (Vercel)

World	Framework	Workflow Time	Wall Time	Overhead	Samples	vs Fastest
▲ Vercel	🥇 Nitro	2.838s (+1.0%)	3.792s (+3.6%)	0.953s	8	1.00x
▲ Vercel	Express	2.853s (+0.9%)	3.886s (+5.3% 🔺)	1.033s	8	1.01x
▲ Vercel	Next.js (Turbopack)	3.017s (+5.7% 🔺)	4.024s (+9.6% 🔺)	1.007s	8	1.06x

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

Promise.race with 25 concurrent steps

💻 Local Development

World	Framework	Workflow Time	Wall Time	Overhead	Samples	vs Fastest
💻 Local	🥇 Next.js (Turbopack)	2.536s (~)	3.102s (+1.6%)	0.566s	10	1.00x
💻 Local	Express	2.568s (-2.8%)	3.022s (~)	0.454s	10	1.01x
💻 Local	Nitro	2.596s (-0.5%)	3.022s (~)	0.427s	10	1.02x
🐘 Postgres	Nitro	11.622s (-3.4%)	12.050s (-2.8%)	0.428s	3	4.58x
🐘 Postgres	Express	12.974s (+6.7% 🔺)	13.022s (+2.5%)	0.048s	3	5.12x
🐘 Postgres	Next.js (Turbopack)	13.121s (-5.6% 🟢)	13.705s (-4.6%)	0.584s	3	5.17x

▲ Production (Vercel)

World	Framework	Workflow Time	Wall Time	Overhead	Samples	vs Fastest
▲ Vercel	🥇 Nitro	3.089s (-21.8% 🟢)	3.948s (-18.8% 🟢)	0.859s	8	1.00x
▲ Vercel	Next.js (Turbopack)	3.263s (+4.6%)	4.032s (+6.9% 🔺)	0.769s	8	1.06x
▲ Vercel	Express	3.657s (+2.4%)	4.312s (-0.8%)	0.655s	7	1.18x

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

Stream Benchmarks(includes TTFB metrics)

workflow with stream

💻 Local Development

World	Framework	Workflow Time	TTFB	Slurp	Wall Time	Overhead	Samples	vs Fastest
💻 Local	🥇 Next.js (Turbopack)	0.144s (+1.6%)	1.004s (~)	0.016s (-12.2% 🟢)	1.027s (~)	0.884s	10	1.00x
💻 Local	Express	0.184s (-0.7%)	0.992s (~)	0.018s (+19.9% 🔺)	1.024s (~)	0.841s	10	1.28x
💻 Local	Nitro	0.188s (-0.6%)	0.993s (~)	0.015s (-2.6%)	1.022s (~)	0.834s	10	1.31x
🐘 Postgres	Next.js (Turbopack)	1.304s (+107.0% 🔺)	2.040s (+109.8% 🔺)	0.000s (NaN%)	2.120s (+108.6% 🔺)	0.816s	10	9.07x
🐘 Postgres	Nitro	1.451s (-41.4% 🟢)	2.266s (-11.6% 🟢)	0.000s (-100.0% 🟢)	2.314s (-23.2% 🟢)	0.863s	10	10.10x
🐘 Postgres	Express	2.104s (+65.2% 🔺)	2.936s (+66.6% 🔺)	0.000s (NaN%)	3.016s (+49.7% 🔺)	0.911s	10	14.64x

▲ Production (Vercel)

World	Framework	Workflow Time	TTFB	Slurp	Wall Time	Overhead	Samples	vs Fastest
▲ Vercel	🥇 Next.js (Turbopack)	2.932s (-4.8%)	3.245s (+2.3%)	0.537s (-33.6% 🟢)	4.267s (-5.6% 🟢)	1.335s	10	1.00x
▲ Vercel	Nitro	3.058s (-0.7%)	3.228s (+1.8%)	0.672s (-35.1% 🟢)	4.459s (-7.0% 🟢)	1.401s	10	1.04x
▲ Vercel	Express	3.100s (+2.6%)	3.330s (+2.9%)	0.518s (-13.5% 🟢)	4.388s (+1.7%)	1.288s	10	1.06x

🔍 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)	7/8
🐘 Postgres	Next.js (Turbopack)	3/8
▲ Vercel	Nitro	4/8

Fastest World by Framework

Winner determined by most benchmark wins

Framework	🥇 Fastest World	Wins
Express	💻 Local	8/8
Next.js (Turbopack)	💻 Local	8/8
Nitro	💻 Local	8/8

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

[vercel]

🔧 Build Fix:

The OpenAI class is not constructable in the imported module. This is a type error where the code is trying to instantiate the OpenAI class, but the module export doesn't provide a constructor signature.

[TooTallNate]

Enable class serialization in client mode to support passing class instances to workflow functions.

What changed?

• Added support for class serialization transformations in "client" mode
• The plugin now generates necessary imports and registration calls for classes that need serialization in client mode
• When classes are detected that need serialization, the plugin:
  • Imports registerSerializationClass from "workflow/internal/class-serialization"
  • Adds registration calls for each class with a unique class ID
• Updated test outputs to reflect these changes

How to test?

1. Create a class with serialization methods (using WORKFLOW_SERIALIZE and WORKFLOW_DESERIALIZE symbols)
2. Use the class in a client-side context where it's passed to a workflow function
3. Verify that the class is properly serialized and deserialized when passed between client and workflow

Why make this change?

Previously, class serialization was only enabled in workflow mode, which meant that classes couldn't be properly serialized when passed from client code to workflow functions. This change ensures that classes with custom serialization methods work correctly when used as arguments to start(workflow) calls from client code.

[changeset-bot]

🦋 Changeset detected

Latest commit: 1a72c70

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

This PR includes changesets to release 15 packages

Name	Type
@workflow/swc-plugin	Patch
@workflow/astro	Patch
@workflow/builders	Patch
@workflow/cli	Patch
@workflow/nest	Patch
@workflow/next	Patch
@workflow/nitro	Patch
@workflow/rollup	Patch
@workflow/sveltekit	Patch
workflow	Patch
@workflow/world-testing	Patch
@workflow/example-nest	Patch
@workflow/docs-typecheck	Patch
@workflow/nuxt	Patch
@workflow/ai	Patch

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

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

[github-actions]

🧪 E2E Test Results

❌ Some tests failed

Summary

	Passed	Failed	Skipped	Total
✅ ▲ Vercel Production	457	0	38	495
❌ 💻 Local Development	416	2	32	450
✅ 📦 Local Production	418	0	32	450
✅ 🐘 Local Postgres	418	0	32	450
✅ 🪟 Windows	45	0	0	45
❌ 🌍 Community Worlds	31	161	0	192
✅ 📋 Other	123	0	12	135
Total	1908	163	146	2217

❌ Failed Tests

💻 Local Development (2 failed)

astro-stable (2 failed):

• 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

🌍 Community Worlds (161 failed)

mongodb (40 failed):

• addTenWorkflow
• addTenWorkflow
• should work with react rendering in step
• promiseAllWorkflow
• promiseRaceWorkflow
• promiseAnyWorkflow
• readableStreamWorkflow
• hookWorkflow
• webhookWorkflow
• sleepingWorkflow
• nullByteWorkflow
• workflowAndStepMetadataWorkflow
• outputStreamWorkflow
• outputStreamInsideStepWorkflow - getWritable() called inside step functions
• 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
• 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
• pages router addTenWorkflow via pages router
• pages router promiseAllWorkflow via pages router
• pages router sleepingWorkflow via pages router

redis (40 failed):

• addTenWorkflow
• addTenWorkflow
• should work with react rendering in step
• promiseAllWorkflow
• promiseRaceWorkflow
• promiseAnyWorkflow
• readableStreamWorkflow
• hookWorkflow
• webhookWorkflow
• sleepingWorkflow
• nullByteWorkflow
• workflowAndStepMetadataWorkflow
• outputStreamWorkflow
• outputStreamInsideStepWorkflow - getWritable() called inside step functions
• 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
• 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
• pages router addTenWorkflow via pages router
• pages router promiseAllWorkflow via pages router
• pages router sleepingWorkflow via pages router

starter (41 failed):

• addTenWorkflow
• addTenWorkflow
• should work with react rendering in step
• promiseAllWorkflow
• promiseRaceWorkflow
• promiseAnyWorkflow
• readableStreamWorkflow
• hookWorkflow
• webhookWorkflow
• sleepingWorkflow
• nullByteWorkflow
• workflowAndStepMetadataWorkflow
• outputStreamWorkflow
• outputStreamInsideStepWorkflow - getWritable() called inside step functions
• 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 (CLI) - workflow health command reports healthy endpoints
• 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
• pages router addTenWorkflow via pages router
• pages router promiseAllWorkflow via pages router
• pages router sleepingWorkflow via pages router

turso (40 failed):

• addTenWorkflow
• addTenWorkflow
• should work with react rendering in step
• promiseAllWorkflow
• promiseRaceWorkflow
• promiseAnyWorkflow
• readableStreamWorkflow
• hookWorkflow
• webhookWorkflow
• sleepingWorkflow
• nullByteWorkflow
• workflowAndStepMetadataWorkflow
• outputStreamWorkflow
• outputStreamInsideStepWorkflow - getWritable() called inside step functions
• 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
• 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
• 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	41	0	4
✅ example	41	0	4
✅ express	41	0	4
✅ fastify	41	0	4
✅ hono	41	0	4
✅ nextjs-turbopack	44	0	1
✅ nextjs-webpack	44	0	1
✅ nitro	41	0	4
✅ nuxt	41	0	4
✅ sveltekit	41	0	4
✅ vite	41	0	4

❌ 💻 Local Development

App	Passed	Failed	Skipped
❌ astro-stable	39	2	4
✅ express-stable	41	0	4
✅ fastify-stable	41	0	4
✅ hono-stable	41	0	4
✅ nextjs-turbopack-stable	45	0	0
✅ nextjs-webpack-stable	45	0	0
✅ nitro-stable	41	0	4
✅ nuxt-stable	41	0	4
✅ sveltekit-stable	41	0	4
✅ vite-stable	41	0	4

✅ 📦 Local Production

App	Passed	Failed	Skipped
✅ astro-stable	41	0	4
✅ express-stable	41	0	4
✅ fastify-stable	41	0	4
✅ hono-stable	41	0	4
✅ nextjs-turbopack-stable	45	0	0
✅ nextjs-webpack-stable	45	0	0
✅ nitro-stable	41	0	4
✅ nuxt-stable	41	0	4
✅ sveltekit-stable	41	0	4
✅ vite-stable	41	0	4

✅ 🐘 Local Postgres

App	Passed	Failed	Skipped
✅ astro-stable	41	0	4
✅ express-stable	41	0	4
✅ fastify-stable	41	0	4
✅ hono-stable	41	0	4
✅ nextjs-turbopack-stable	45	0	0
✅ nextjs-webpack-stable	45	0	0
✅ nitro-stable	41	0	4
✅ nuxt-stable	41	0	4
✅ sveltekit-stable	41	0	4
✅ vite-stable	41	0	4

✅ 🪟 Windows

App	Passed	Failed	Skipped
✅ nextjs-turbopack	45	0	0

❌ 🌍 Community Worlds

App	Passed	Failed	Skipped
✅ mongodb-dev	3	0	0
❌ mongodb	5	40	0
✅ redis-dev	3	0	0
❌ redis	5	40	0
✅ starter-dev	3	0	0
❌ starter	4	41	0
✅ turso-dev	3	0	0
❌ turso	5	40	0

✅ 📋 Other

App	Passed	Failed	Skipped
✅ e2e-local-dev-nest-stable	41	0	4
✅ e2e-local-postgres-nest-stable	41	0	4
✅ e2e-local-prod-nest-stable	41	0	4

---

📋 View full workflow run

---

❌ Some E2E test jobs failed:

• Vercel Prod: success
• Local Dev: failure
• Local Prod: success
• Local Postgres: success
• Windows: success

Check the workflow run for details.

[vercel]

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

Project	Deployment	Review	Updated (UTC)
example-nextjs-workflow-turbopack	Ready	Preview, Comment	Jan 27, 2026 7:00am
example-nextjs-workflow-webpack	Ready	Preview, Comment	Jan 27, 2026 7:00am
example-workflow	Ready	Preview, Comment	Jan 27, 2026 7:00am
workbench-astro-workflow	Ready	Preview, Comment	Jan 27, 2026 7:00am
workbench-express-workflow	Ready	Preview, Comment	Jan 27, 2026 7:00am
workbench-fastify-workflow	Ready	Preview, Comment	Jan 27, 2026 7:00am
workbench-hono-workflow	Ready	Preview, Comment	Jan 27, 2026 7:00am
workbench-nitro-workflow	Ready	Preview, Comment	Jan 27, 2026 7:00am
workbench-nuxt-workflow	Ready	Preview, Comment	Jan 27, 2026 7:00am
workbench-sveltekit-workflow	Ready	Preview, Comment	Jan 27, 2026 7:00am
workbench-vite-workflow	Ready	Preview, Comment	Jan 27, 2026 7:00am
workflow-docs	Ready	Preview, Comment	Jan 27, 2026 7:00am
workflow-nest	Error		Jan 27, 2026 7:00am

[TooTallNate]

• Enable custom class serialization transformations for "client" mode #860 👈 (View in Graphite)
• main

This stack of pull requests is managed by Graphite. Learn more about stacking.

[Copilot]

Pull request overview

This PR enables custom class serialization transformations for "client" mode in the SWC plugin. Previously, class serialization was only handled in workflow and step modes. This change ensures that classes with custom serialization methods can be properly serialized when passed from client code to workflow functions via start(workflow) calls.

Changes:

• Added import generation for registerSerializationClass in client mode when classes need serialization
• Added registration call generation for classes in client mode (both Module and Script cases)
• Updated test fixtures to reflect the new client mode behavior with serialization imports and registration calls

Reviewed changes

Copilot reviewed 7 out of 7 changed files in this pull request and generated 3 comments.

Show a summary per file

File	Description
packages/swc-plugin-workflow/transform/src/lib.rs	Added logic to generate serialization imports and registration calls for client mode in both Module and Script cases
packages/swc-plugin-workflow/transform/tests/fixture/static-method-step/output-client.js	Added expected import and registration call for MyService class
packages/swc-plugin-workflow/transform/tests/fixture/custom-serialization/output-client.js	Added expected import and registration call for Point class
packages/swc-plugin-workflow/transform/tests/fixture/custom-serialization-local-const/output-client.js	Added expected import and registration calls for Circle, Rectangle, and Triangle classes
packages/swc-plugin-workflow/transform/tests/fixture/custom-serialization-imported/output-client.js	Added expected import and registration calls for Color and Vector classes
packages/swc-plugin-workflow/transform/tests/errors/instance-methods/output-client.js	Added expected import and registration call for TestClass
.changeset/modern-clubs-own.md	Added changeset documenting this patch change

---

💡 Add Copilot custom instructions for smarter, more guided reviews. Learn how to get started.

[ijjk]

Seems good but the deduplication callout from copilot does seem good as well

[github-actions]

📊 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	🥇 Next.js (Turbopack)	0.041s (-16.4% 🟢)	1.019s (~)	0.978s	10	1.00x
💻 Local	Express	0.043s (-1.6%)	1.008s (-1.3%)	0.965s	10	1.04x
💻 Local	Nitro	0.043s (-11.1% 🟢)	1.007s (~)	0.964s	10	1.06x
🐘 Postgres	Express	0.127s (-48.6% 🟢)	1.015s (~)	0.888s	10	3.10x
🐘 Postgres	Nitro	0.162s (-60.9% 🟢)	1.026s (+1.2%)	0.864s	10	3.96x
🐘 Postgres	Next.js (Turbopack)	0.242s (+100.4% 🔺)	1.021s (~)	0.778s	10	5.93x

▲ Production (Vercel)

World	Framework	Workflow Time	Wall Time	Overhead	Samples	vs Fastest
▲ Vercel	🥇 Nitro	0.596s (-11.7% 🟢)	1.698s (+12.3% 🔺)	1.101s	10	1.00x
▲ Vercel	Express	0.629s (-18.0% 🟢)	1.601s (-5.4% 🟢)	0.972s	10	1.05x
▲ Vercel	Next.js (Turbopack)	0.695s (-17.4% 🟢)	1.553s (-9.9% 🟢)	0.858s	10	1.17x

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

workflow with 1 step

💻 Local Development

World	Framework	Workflow Time	Wall Time	Overhead	Samples	vs Fastest
💻 Local	🥇 Next.js (Turbopack)	1.103s (~)	2.012s (~)	0.909s	10	1.00x
💻 Local	Express	1.116s (~)	2.008s (~)	0.892s	10	1.01x
💻 Local	Nitro	1.118s (~)	2.007s (~)	0.889s	10	1.01x
🐘 Postgres	Next.js (Turbopack)	2.254s (+17.5% 🔺)	3.019s (+49.8% 🔺)	0.765s	10	2.04x
🐘 Postgres	Express	2.472s (+17.8% 🔺)	3.013s (~)	0.541s	10	2.24x
🐘 Postgres	Nitro	2.473s (+9.2% 🔺)	3.014s (~)	0.542s	10	2.24x

▲ Production (Vercel)

World	Framework	Workflow Time	Wall Time	Overhead	Samples	vs Fastest
▲ Vercel	🥇 Express	2.730s (-1.8%)	3.744s (+3.0%)	1.013s	10	1.00x
▲ Vercel	Nitro	2.874s (~)	3.779s (+4.6%)	0.905s	10	1.05x
▲ Vercel	Next.js (Turbopack)	2.952s (+1.5%)	3.663s (-0.7%)	0.711s	10	1.08x

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

workflow with 10 sequential steps

💻 Local Development

World	Framework	Workflow Time	Wall Time	Overhead	Samples	vs Fastest
💻 Local	🥇 Next.js (Turbopack)	10.716s (~)	11.018s (~)	0.302s	5	1.00x
💻 Local	Nitro	10.841s (~)	11.014s (~)	0.173s	5	1.01x
💻 Local	Express	10.852s (~)	11.013s (~)	0.161s	5	1.01x
🐘 Postgres	Nitro	20.292s (+0.6%)	21.041s (~)	0.750s	5	1.89x
🐘 Postgres	Express	20.310s (+30.5% 🔺)	21.037s (+31.2% 🔺)	0.726s	5	1.90x
🐘 Postgres	Next.js (Turbopack)	20.354s (+40.4% 🔺)	21.043s (+39.9% 🔺)	0.689s	5	1.90x

▲ Production (Vercel)

World	Framework	Workflow Time	Wall Time	Overhead	Samples	vs Fastest
▲ Vercel	🥇 Nitro	22.236s (-6.6% 🟢)	23.066s (-5.8% 🟢)	0.830s	5	1.00x
▲ Vercel	Express	22.515s (-6.9% 🟢)	23.414s (-6.1% 🟢)	0.898s	5	1.01x
▲ Vercel	Next.js (Turbopack)	22.838s (~)	23.452s (-1.4%)	0.614s	5	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
💻 Local	🥇 Next.js (Turbopack)	1.389s (~)	2.012s (~)	0.622s	15	1.00x
💻 Local	Nitro	1.413s (~)	2.007s (~)	0.594s	15	1.02x
💻 Local	Express	1.414s (-0.8%)	2.007s (~)	0.593s	15	1.02x
🐘 Postgres	Next.js (Turbopack)	2.200s (+3.3%)	2.853s (+5.3% 🔺)	0.653s	11	1.58x
🐘 Postgres	Nitro	2.305s (-4.9%)	2.678s (-11.0% 🟢)	0.373s	12	1.66x
🐘 Postgres	Express	2.515s (+21.3% 🔺)	3.014s (+16.0% 🔺)	0.499s	10	1.81x

▲ Production (Vercel)

World	Framework	Workflow Time	Wall Time	Overhead	Samples	vs Fastest
▲ Vercel	🥇 Next.js (Turbopack)	3.000s (-3.5%)	3.773s (-5.5% 🟢)	0.773s	8	1.00x
▲ Vercel	Nitro	3.406s (+7.1% 🔺)	4.360s (+11.9% 🔺)	0.954s	7	1.14x
▲ Vercel	Express	3.551s (+21.7% 🔺)	4.414s (+16.5% 🔺)	0.863s	7	1.18x

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

Promise.all with 25 concurrent steps

💻 Local Development

World	Framework	Workflow Time	Wall Time	Overhead	Samples	vs Fastest
💻 Local	🥇 Next.js (Turbopack)	2.472s (~)	3.066s (-4.3%)	0.594s	10	1.00x
💻 Local	Express	2.502s (-2.0%)	3.029s (+0.5%)	0.527s	10	1.01x
💻 Local	Nitro	2.510s (-2.1%)	3.026s (~)	0.515s	10	1.02x
🐘 Postgres	Express	7.934s (-20.5% 🟢)	8.305s (-20.5% 🟢)	0.371s	4	3.21x
🐘 Postgres	Nitro	8.839s (+18.5% 🔺)	9.274s (+14.9% 🔺)	0.435s	4	3.58x
🐘 Postgres	Next.js (Turbopack)	11.559s (-0.8%)	12.037s (-0.7%)	0.478s	3	4.68x

▲ Production (Vercel)

World	Framework	Workflow Time	Wall Time	Overhead	Samples	vs Fastest
▲ Vercel	🥇 Next.js (Turbopack)	3.235s (-6.5% 🟢)	4.052s (-0.7%)	0.817s	8	1.00x
▲ Vercel	Express	3.374s (+2.4%)	4.168s (+2.8%)	0.795s	8	1.04x
▲ Vercel	Nitro	3.535s (+15.7% 🔺)	4.228s (+10.6% 🔺)	0.694s	8	1.09x

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

Promise.race with 10 concurrent steps

💻 Local Development

World	Framework	Workflow Time	Wall Time	Overhead	Samples	vs Fastest
💻 Local	🥇 Nitro	1.409s (-2.7%)	2.007s (~)	0.598s	15	1.00x
💻 Local	Next.js (Turbopack)	1.427s (+1.0%)	2.013s (~)	0.586s	15	1.01x
💻 Local	Express	1.434s (~)	2.006s (~)	0.572s	15	1.02x
🐘 Postgres	Nitro	1.967s (-8.0% 🟢)	2.477s (-4.7%)	0.511s	13	1.40x
🐘 Postgres	Express	2.061s (+14.5% 🔺)	2.528s (+13.3% 🔺)	0.467s	12	1.46x
🐘 Postgres	Next.js (Turbopack)	2.299s (-2.5%)	2.746s (-9.2% 🟢)	0.447s	11	1.63x

▲ Production (Vercel)

World	Framework	Workflow Time	Wall Time	Overhead	Samples	vs Fastest
▲ Vercel	🥇 Nitro	2.838s (+1.0%)	3.792s (+3.6%)	0.953s	8	1.00x
▲ Vercel	Express	2.853s (+0.9%)	3.886s (+5.3% 🔺)	1.033s	8	1.01x
▲ Vercel	Next.js (Turbopack)	3.017s (+5.7% 🔺)	4.024s (+9.6% 🔺)	1.007s	8	1.06x

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

Promise.race with 25 concurrent steps

💻 Local Development

World	Framework	Workflow Time	Wall Time	Overhead	Samples	vs Fastest
💻 Local	🥇 Next.js (Turbopack)	2.536s (~)	3.102s (+1.6%)	0.566s	10	1.00x
💻 Local	Express	2.568s (-2.8%)	3.022s (~)	0.454s	10	1.01x
💻 Local	Nitro	2.596s (-0.5%)	3.022s (~)	0.427s	10	1.02x
🐘 Postgres	Nitro	11.622s (-3.4%)	12.050s (-2.8%)	0.428s	3	4.58x
🐘 Postgres	Express	12.974s (+6.7% 🔺)	13.022s (+2.5%)	0.048s	3	5.12x
🐘 Postgres	Next.js (Turbopack)	13.121s (-5.6% 🟢)	13.705s (-4.6%)	0.584s	3	5.17x

▲ Production (Vercel)

World	Framework	Workflow Time	Wall Time	Overhead	Samples	vs Fastest
▲ Vercel	🥇 Nitro	3.089s (-21.8% 🟢)	3.948s (-18.8% 🟢)	0.859s	8	1.00x
▲ Vercel	Next.js (Turbopack)	3.263s (+4.6%)	4.032s (+6.9% 🔺)	0.769s	8	1.06x
▲ Vercel	Express	3.657s (+2.4%)	4.312s (-0.8%)	0.655s	7	1.18x

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

Stream Benchmarks(includes TTFB metrics)

workflow with stream

💻 Local Development

World	Framework	Workflow Time	TTFB	Slurp	Wall Time	Overhead	Samples	vs Fastest
💻 Local	🥇 Next.js (Turbopack)	0.144s (+1.6%)	1.004s (~)	0.016s (-12.2% 🟢)	1.027s (~)	0.884s	10	1.00x
💻 Local	Express	0.184s (-0.7%)	0.992s (~)	0.018s (+19.9% 🔺)	1.024s (~)	0.841s	10	1.28x
💻 Local	Nitro	0.188s (-0.6%)	0.993s (~)	0.015s (-2.6%)	1.022s (~)	0.834s	10	1.31x
🐘 Postgres	Next.js (Turbopack)	1.304s (+107.0% 🔺)	2.040s (+109.8% 🔺)	0.000s (NaN%)	2.120s (+108.6% 🔺)	0.816s	10	9.07x
🐘 Postgres	Nitro	1.451s (-41.4% 🟢)	2.266s (-11.6% 🟢)	0.000s (-100.0% 🟢)	2.314s (-23.2% 🟢)	0.863s	10	10.10x
🐘 Postgres	Express	2.104s (+65.2% 🔺)	2.936s (+66.6% 🔺)	0.000s (NaN%)	3.016s (+49.7% 🔺)	0.911s	10	14.64x

▲ Production (Vercel)

World	Framework	Workflow Time	TTFB	Slurp	Wall Time	Overhead	Samples	vs Fastest
▲ Vercel	🥇 Next.js (Turbopack)	2.932s (-4.8%)	3.245s (+2.3%)	0.537s (-33.6% 🟢)	4.267s (-5.6% 🟢)	1.335s	10	1.00x
▲ Vercel	Nitro	3.058s (-0.7%)	3.228s (+1.8%)	0.672s (-35.1% 🟢)	4.459s (-7.0% 🟢)	1.401s	10	1.04x
▲ Vercel	Express	3.100s (+2.6%)	3.330s (+2.9%)	0.518s (-13.5% 🟢)	4.388s (+1.7%)	1.288s	10	1.06x

🔍 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)	7/8
🐘 Postgres	Next.js (Turbopack)	3/8
▲ Vercel	Nitro	4/8

Fastest World by Framework

Winner determined by most benchmark wins

Framework	🥇 Fastest World	Wins
Express	💻 Local	8/8
Next.js (Turbopack)	💻 Local	8/8
Nitro	💻 Local	8/8

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

[vercel]

🔧 Build Fix:

The OpenAI class is not constructable in the imported module. This is a type error where the code is trying to instantiate the OpenAI class, but the module export doesn't provide a constructor signature.

[TooTallNate]

Enable class serialization in client mode to support passing class instances to workflow functions.

What changed?

• Added support for class serialization transformations in "client" mode
• The plugin now generates necessary imports and registration calls for classes that need serialization in client mode
• When classes are detected that need serialization, the plugin:
  • Imports registerSerializationClass from "workflow/internal/class-serialization"
  • Adds registration calls for each class with a unique class ID
• Updated test outputs to reflect these changes

How to test?

1. Create a class with serialization methods (using WORKFLOW_SERIALIZE and WORKFLOW_DESERIALIZE symbols)
2. Use the class in a client-side context where it's passed to a workflow function
3. Verify that the class is properly serialized and deserialized when passed between client and workflow

Why make this change?

Previously, class serialization was only enabled in workflow mode, which meant that classes couldn't be properly serialized when passed from client code to workflow functions. This change ensures that classes with custom serialization methods work correctly when used as arguments to start(workflow) calls from client code.

[changeset-bot]

🦋 Changeset detected

Latest commit: 1a72c70

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

This PR includes changesets to release 15 packages

Name	Type
@workflow/swc-plugin	Patch
@workflow/astro	Patch
@workflow/builders	Patch
@workflow/cli	Patch
@workflow/nest	Patch
@workflow/next	Patch
@workflow/nitro	Patch
@workflow/rollup	Patch
@workflow/sveltekit	Patch
workflow	Patch
@workflow/world-testing	Patch
@workflow/example-nest	Patch
@workflow/docs-typecheck	Patch
@workflow/nuxt	Patch
@workflow/ai	Patch

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

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

[github-actions]

🧪 E2E Test Results

❌ Some tests failed

Summary

	Passed	Failed	Skipped	Total
✅ ▲ Vercel Production	457	0	38	495
❌ 💻 Local Development	416	2	32	450
✅ 📦 Local Production	418	0	32	450
✅ 🐘 Local Postgres	418	0	32	450
✅ 🪟 Windows	45	0	0	45
❌ 🌍 Community Worlds	31	161	0	192
✅ 📋 Other	123	0	12	135
Total	1908	163	146	2217

❌ Failed Tests

💻 Local Development (2 failed)

astro-stable (2 failed):

• 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

🌍 Community Worlds (161 failed)

mongodb (40 failed):

• addTenWorkflow
• addTenWorkflow
• should work with react rendering in step
• promiseAllWorkflow
• promiseRaceWorkflow
• promiseAnyWorkflow
• readableStreamWorkflow
• hookWorkflow
• webhookWorkflow
• sleepingWorkflow
• nullByteWorkflow
• workflowAndStepMetadataWorkflow
• outputStreamWorkflow
• outputStreamInsideStepWorkflow - getWritable() called inside step functions
• 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
• 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
• pages router addTenWorkflow via pages router
• pages router promiseAllWorkflow via pages router
• pages router sleepingWorkflow via pages router

redis (40 failed):

• addTenWorkflow
• addTenWorkflow
• should work with react rendering in step
• promiseAllWorkflow
• promiseRaceWorkflow
• promiseAnyWorkflow
• readableStreamWorkflow
• hookWorkflow
• webhookWorkflow
• sleepingWorkflow
• nullByteWorkflow
• workflowAndStepMetadataWorkflow
• outputStreamWorkflow
• outputStreamInsideStepWorkflow - getWritable() called inside step functions
• 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
• 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
• pages router addTenWorkflow via pages router
• pages router promiseAllWorkflow via pages router
• pages router sleepingWorkflow via pages router

starter (41 failed):

• addTenWorkflow
• addTenWorkflow
• should work with react rendering in step
• promiseAllWorkflow
• promiseRaceWorkflow
• promiseAnyWorkflow
• readableStreamWorkflow
• hookWorkflow
• webhookWorkflow
• sleepingWorkflow
• nullByteWorkflow
• workflowAndStepMetadataWorkflow
• outputStreamWorkflow
• outputStreamInsideStepWorkflow - getWritable() called inside step functions
• 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 (CLI) - workflow health command reports healthy endpoints
• 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
• pages router addTenWorkflow via pages router
• pages router promiseAllWorkflow via pages router
• pages router sleepingWorkflow via pages router

turso (40 failed):

• addTenWorkflow
• addTenWorkflow
• should work with react rendering in step
• promiseAllWorkflow
• promiseRaceWorkflow
• promiseAnyWorkflow
• readableStreamWorkflow
• hookWorkflow
• webhookWorkflow
• sleepingWorkflow
• nullByteWorkflow
• workflowAndStepMetadataWorkflow
• outputStreamWorkflow
• outputStreamInsideStepWorkflow - getWritable() called inside step functions
• 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
• 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
• 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	41	0	4
✅ example	41	0	4
✅ express	41	0	4
✅ fastify	41	0	4
✅ hono	41	0	4
✅ nextjs-turbopack	44	0	1
✅ nextjs-webpack	44	0	1
✅ nitro	41	0	4
✅ nuxt	41	0	4
✅ sveltekit	41	0	4
✅ vite	41	0	4

❌ 💻 Local Development

App	Passed	Failed	Skipped
❌ astro-stable	39	2	4
✅ express-stable	41	0	4
✅ fastify-stable	41	0	4
✅ hono-stable	41	0	4
✅ nextjs-turbopack-stable	45	0	0
✅ nextjs-webpack-stable	45	0	0
✅ nitro-stable	41	0	4
✅ nuxt-stable	41	0	4
✅ sveltekit-stable	41	0	4
✅ vite-stable	41	0	4

✅ 📦 Local Production

App	Passed	Failed	Skipped
✅ astro-stable	41	0	4
✅ express-stable	41	0	4
✅ fastify-stable	41	0	4
✅ hono-stable	41	0	4
✅ nextjs-turbopack-stable	45	0	0
✅ nextjs-webpack-stable	45	0	0
✅ nitro-stable	41	0	4
✅ nuxt-stable	41	0	4
✅ sveltekit-stable	41	0	4
✅ vite-stable	41	0	4

✅ 🐘 Local Postgres

App	Passed	Failed	Skipped
✅ astro-stable	41	0	4
✅ express-stable	41	0	4
✅ fastify-stable	41	0	4
✅ hono-stable	41	0	4
✅ nextjs-turbopack-stable	45	0	0
✅ nextjs-webpack-stable	45	0	0
✅ nitro-stable	41	0	4
✅ nuxt-stable	41	0	4
✅ sveltekit-stable	41	0	4
✅ vite-stable	41	0	4

✅ 🪟 Windows

App	Passed	Failed	Skipped
✅ nextjs-turbopack	45	0	0

❌ 🌍 Community Worlds

App	Passed	Failed	Skipped
✅ mongodb-dev	3	0	0
❌ mongodb	5	40	0
✅ redis-dev	3	0	0
❌ redis	5	40	0
✅ starter-dev	3	0	0
❌ starter	4	41	0
✅ turso-dev	3	0	0
❌ turso	5	40	0

✅ 📋 Other

App	Passed	Failed	Skipped
✅ e2e-local-dev-nest-stable	41	0	4
✅ e2e-local-postgres-nest-stable	41	0	4
✅ e2e-local-prod-nest-stable	41	0	4

---

📋 View full workflow run

---

❌ Some E2E test jobs failed:

• Vercel Prod: success
• Local Dev: failure
• Local Prod: success
• Local Postgres: success
• Windows: success

Check the workflow run for details.

[vercel]

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

Project	Deployment	Review	Updated (UTC)
example-nextjs-workflow-turbopack	Ready	Preview, Comment	Jan 27, 2026 7:00am
example-nextjs-workflow-webpack	Ready	Preview, Comment	Jan 27, 2026 7:00am
example-workflow	Ready	Preview, Comment	Jan 27, 2026 7:00am
workbench-astro-workflow	Ready	Preview, Comment	Jan 27, 2026 7:00am
workbench-express-workflow	Ready	Preview, Comment	Jan 27, 2026 7:00am
workbench-fastify-workflow	Ready	Preview, Comment	Jan 27, 2026 7:00am
workbench-hono-workflow	Ready	Preview, Comment	Jan 27, 2026 7:00am
workbench-nitro-workflow	Ready	Preview, Comment	Jan 27, 2026 7:00am
workbench-nuxt-workflow	Ready	Preview, Comment	Jan 27, 2026 7:00am
workbench-sveltekit-workflow	Ready	Preview, Comment	Jan 27, 2026 7:00am
workbench-vite-workflow	Ready	Preview, Comment	Jan 27, 2026 7:00am
workflow-docs	Ready	Preview, Comment	Jan 27, 2026 7:00am
workflow-nest	Error		Jan 27, 2026 7:00am

[TooTallNate]

• Enable custom class serialization transformations for "client" mode #860 👈 (View in Graphite)
• main

This stack of pull requests is managed by Graphite. Learn more about stacking.

[Copilot]

Pull request overview

This PR enables custom class serialization transformations for "client" mode in the SWC plugin. Previously, class serialization was only handled in workflow and step modes. This change ensures that classes with custom serialization methods can be properly serialized when passed from client code to workflow functions via start(workflow) calls.

Changes:

• Added import generation for registerSerializationClass in client mode when classes need serialization
• Added registration call generation for classes in client mode (both Module and Script cases)
• Updated test fixtures to reflect the new client mode behavior with serialization imports and registration calls

Reviewed changes

Copilot reviewed 7 out of 7 changed files in this pull request and generated 3 comments.

Show a summary per file

File	Description
packages/swc-plugin-workflow/transform/src/lib.rs	Added logic to generate serialization imports and registration calls for client mode in both Module and Script cases
packages/swc-plugin-workflow/transform/tests/fixture/static-method-step/output-client.js	Added expected import and registration call for MyService class
packages/swc-plugin-workflow/transform/tests/fixture/custom-serialization/output-client.js	Added expected import and registration call for Point class
packages/swc-plugin-workflow/transform/tests/fixture/custom-serialization-local-const/output-client.js	Added expected import and registration calls for Circle, Rectangle, and Triangle classes
packages/swc-plugin-workflow/transform/tests/fixture/custom-serialization-imported/output-client.js	Added expected import and registration calls for Color and Vector classes
packages/swc-plugin-workflow/transform/tests/errors/instance-methods/output-client.js	Added expected import and registration call for TestClass
.changeset/modern-clubs-own.md	Added changeset documenting this patch change

---

💡 Add Copilot custom instructions for smarter, more guided reviews. Learn how to get started.

[ijjk]

Seems good but the deduplication callout from copilot does seem good as well

[github-actions]

📊 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	🥇 Next.js (Turbopack)	0.041s (-16.4% 🟢)	1.019s (~)	0.978s	10	1.00x
💻 Local	Express	0.043s (-1.6%)	1.008s (-1.3%)	0.965s	10	1.04x
💻 Local	Nitro	0.043s (-11.1% 🟢)	1.007s (~)	0.964s	10	1.06x
🐘 Postgres	Express	0.127s (-48.6% 🟢)	1.015s (~)	0.888s	10	3.10x
🐘 Postgres	Nitro	0.162s (-60.9% 🟢)	1.026s (+1.2%)	0.864s	10	3.96x
🐘 Postgres	Next.js (Turbopack)	0.242s (+100.4% 🔺)	1.021s (~)	0.778s	10	5.93x

▲ Production (Vercel)

World	Framework	Workflow Time	Wall Time	Overhead	Samples	vs Fastest
▲ Vercel	🥇 Nitro	0.596s (-11.7% 🟢)	1.698s (+12.3% 🔺)	1.101s	10	1.00x
▲ Vercel	Express	0.629s (-18.0% 🟢)	1.601s (-5.4% 🟢)	0.972s	10	1.05x
▲ Vercel	Next.js (Turbopack)	0.695s (-17.4% 🟢)	1.553s (-9.9% 🟢)	0.858s	10	1.17x

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

workflow with 1 step

💻 Local Development

World	Framework	Workflow Time	Wall Time	Overhead	Samples	vs Fastest
💻 Local	🥇 Next.js (Turbopack)	1.103s (~)	2.012s (~)	0.909s	10	1.00x
💻 Local	Express	1.116s (~)	2.008s (~)	0.892s	10	1.01x
💻 Local	Nitro	1.118s (~)	2.007s (~)	0.889s	10	1.01x
🐘 Postgres	Next.js (Turbopack)	2.254s (+17.5% 🔺)	3.019s (+49.8% 🔺)	0.765s	10	2.04x
🐘 Postgres	Express	2.472s (+17.8% 🔺)	3.013s (~)	0.541s	10	2.24x
🐘 Postgres	Nitro	2.473s (+9.2% 🔺)	3.014s (~)	0.542s	10	2.24x

▲ Production (Vercel)

World	Framework	Workflow Time	Wall Time	Overhead	Samples	vs Fastest
▲ Vercel	🥇 Express	2.730s (-1.8%)	3.744s (+3.0%)	1.013s	10	1.00x
▲ Vercel	Nitro	2.874s (~)	3.779s (+4.6%)	0.905s	10	1.05x
▲ Vercel	Next.js (Turbopack)	2.952s (+1.5%)	3.663s (-0.7%)	0.711s	10	1.08x

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

workflow with 10 sequential steps

💻 Local Development

World	Framework	Workflow Time	Wall Time	Overhead	Samples	vs Fastest
💻 Local	🥇 Next.js (Turbopack)	10.716s (~)	11.018s (~)	0.302s	5	1.00x
💻 Local	Nitro	10.841s (~)	11.014s (~)	0.173s	5	1.01x
💻 Local	Express	10.852s (~)	11.013s (~)	0.161s	5	1.01x
🐘 Postgres	Nitro	20.292s (+0.6%)	21.041s (~)	0.750s	5	1.89x
🐘 Postgres	Express	20.310s (+30.5% 🔺)	21.037s (+31.2% 🔺)	0.726s	5	1.90x
🐘 Postgres	Next.js (Turbopack)	20.354s (+40.4% 🔺)	21.043s (+39.9% 🔺)	0.689s	5	1.90x

▲ Production (Vercel)

World	Framework	Workflow Time	Wall Time	Overhead	Samples	vs Fastest
▲ Vercel	🥇 Nitro	22.236s (-6.6% 🟢)	23.066s (-5.8% 🟢)	0.830s	5	1.00x
▲ Vercel	Express	22.515s (-6.9% 🟢)	23.414s (-6.1% 🟢)	0.898s	5	1.01x
▲ Vercel	Next.js (Turbopack)	22.838s (~)	23.452s (-1.4%)	0.614s	5	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
💻 Local	🥇 Next.js (Turbopack)	1.389s (~)	2.012s (~)	0.622s	15	1.00x
💻 Local	Nitro	1.413s (~)	2.007s (~)	0.594s	15	1.02x
💻 Local	Express	1.414s (-0.8%)	2.007s (~)	0.593s	15	1.02x
🐘 Postgres	Next.js (Turbopack)	2.200s (+3.3%)	2.853s (+5.3% 🔺)	0.653s	11	1.58x
🐘 Postgres	Nitro	2.305s (-4.9%)	2.678s (-11.0% 🟢)	0.373s	12	1.66x
🐘 Postgres	Express	2.515s (+21.3% 🔺)	3.014s (+16.0% 🔺)	0.499s	10	1.81x

▲ Production (Vercel)

World	Framework	Workflow Time	Wall Time	Overhead	Samples	vs Fastest
▲ Vercel	🥇 Next.js (Turbopack)	3.000s (-3.5%)	3.773s (-5.5% 🟢)	0.773s	8	1.00x
▲ Vercel	Nitro	3.406s (+7.1% 🔺)	4.360s (+11.9% 🔺)	0.954s	7	1.14x
▲ Vercel	Express	3.551s (+21.7% 🔺)	4.414s (+16.5% 🔺)	0.863s	7	1.18x

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

Promise.all with 25 concurrent steps

💻 Local Development

World	Framework	Workflow Time	Wall Time	Overhead	Samples	vs Fastest
💻 Local	🥇 Next.js (Turbopack)	2.472s (~)	3.066s (-4.3%)	0.594s	10	1.00x
💻 Local	Express	2.502s (-2.0%)	3.029s (+0.5%)	0.527s	10	1.01x
💻 Local	Nitro	2.510s (-2.1%)	3.026s (~)	0.515s	10	1.02x
🐘 Postgres	Express	7.934s (-20.5% 🟢)	8.305s (-20.5% 🟢)	0.371s	4	3.21x
🐘 Postgres	Nitro	8.839s (+18.5% 🔺)	9.274s (+14.9% 🔺)	0.435s	4	3.58x
🐘 Postgres	Next.js (Turbopack)	11.559s (-0.8%)	12.037s (-0.7%)	0.478s	3	4.68x

▲ Production (Vercel)

World	Framework	Workflow Time	Wall Time	Overhead	Samples	vs Fastest
▲ Vercel	🥇 Next.js (Turbopack)	3.235s (-6.5% 🟢)	4.052s (-0.7%)	0.817s	8	1.00x
▲ Vercel	Express	3.374s (+2.4%)	4.168s (+2.8%)	0.795s	8	1.04x
▲ Vercel	Nitro	3.535s (+15.7% 🔺)	4.228s (+10.6% 🔺)	0.694s	8	1.09x

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

Promise.race with 10 concurrent steps

💻 Local Development

World	Framework	Workflow Time	Wall Time	Overhead	Samples	vs Fastest
💻 Local	🥇 Nitro	1.409s (-2.7%)	2.007s (~)	0.598s	15	1.00x
💻 Local	Next.js (Turbopack)	1.427s (+1.0%)	2.013s (~)	0.586s	15	1.01x
💻 Local	Express	1.434s (~)	2.006s (~)	0.572s	15	1.02x
🐘 Postgres	Nitro	1.967s (-8.0% 🟢)	2.477s (-4.7%)	0.511s	13	1.40x
🐘 Postgres	Express	2.061s (+14.5% 🔺)	2.528s (+13.3% 🔺)	0.467s	12	1.46x
🐘 Postgres	Next.js (Turbopack)	2.299s (-2.5%)	2.746s (-9.2% 🟢)	0.447s	11	1.63x

▲ Production (Vercel)

World	Framework	Workflow Time	Wall Time	Overhead	Samples	vs Fastest
▲ Vercel	🥇 Nitro	2.838s (+1.0%)	3.792s (+3.6%)	0.953s	8	1.00x
▲ Vercel	Express	2.853s (+0.9%)	3.886s (+5.3% 🔺)	1.033s	8	1.01x
▲ Vercel	Next.js (Turbopack)	3.017s (+5.7% 🔺)	4.024s (+9.6% 🔺)	1.007s	8	1.06x

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

Promise.race with 25 concurrent steps

💻 Local Development

World	Framework	Workflow Time	Wall Time	Overhead	Samples	vs Fastest
💻 Local	🥇 Next.js (Turbopack)	2.536s (~)	3.102s (+1.6%)	0.566s	10	1.00x
💻 Local	Express	2.568s (-2.8%)	3.022s (~)	0.454s	10	1.01x
💻 Local	Nitro	2.596s (-0.5%)	3.022s (~)	0.427s	10	1.02x
🐘 Postgres	Nitro	11.622s (-3.4%)	12.050s (-2.8%)	0.428s	3	4.58x
🐘 Postgres	Express	12.974s (+6.7% 🔺)	13.022s (+2.5%)	0.048s	3	5.12x
🐘 Postgres	Next.js (Turbopack)	13.121s (-5.6% 🟢)	13.705s (-4.6%)	0.584s	3	5.17x

▲ Production (Vercel)

World	Framework	Workflow Time	Wall Time	Overhead	Samples	vs Fastest
▲ Vercel	🥇 Nitro	3.089s (-21.8% 🟢)	3.948s (-18.8% 🟢)	0.859s	8	1.00x
▲ Vercel	Next.js (Turbopack)	3.263s (+4.6%)	4.032s (+6.9% 🔺)	0.769s	8	1.06x
▲ Vercel	Express	3.657s (+2.4%)	4.312s (-0.8%)	0.655s	7	1.18x

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

Stream Benchmarks(includes TTFB metrics)

workflow with stream

💻 Local Development

World	Framework	Workflow Time	TTFB	Slurp	Wall Time	Overhead	Samples	vs Fastest
💻 Local	🥇 Next.js (Turbopack)	0.144s (+1.6%)	1.004s (~)	0.016s (-12.2% 🟢)	1.027s (~)	0.884s	10	1.00x
💻 Local	Express	0.184s (-0.7%)	0.992s (~)	0.018s (+19.9% 🔺)	1.024s (~)	0.841s	10	1.28x
💻 Local	Nitro	0.188s (-0.6%)	0.993s (~)	0.015s (-2.6%)	1.022s (~)	0.834s	10	1.31x
🐘 Postgres	Next.js (Turbopack)	1.304s (+107.0% 🔺)	2.040s (+109.8% 🔺)	0.000s (NaN%)	2.120s (+108.6% 🔺)	0.816s	10	9.07x
🐘 Postgres	Nitro	1.451s (-41.4% 🟢)	2.266s (-11.6% 🟢)	0.000s (-100.0% 🟢)	2.314s (-23.2% 🟢)	0.863s	10	10.10x
🐘 Postgres	Express	2.104s (+65.2% 🔺)	2.936s (+66.6% 🔺)	0.000s (NaN%)	3.016s (+49.7% 🔺)	0.911s	10	14.64x

▲ Production (Vercel)

World	Framework	Workflow Time	TTFB	Slurp	Wall Time	Overhead	Samples	vs Fastest
▲ Vercel	🥇 Next.js (Turbopack)	2.932s (-4.8%)	3.245s (+2.3%)	0.537s (-33.6% 🟢)	4.267s (-5.6% 🟢)	1.335s	10	1.00x
▲ Vercel	Nitro	3.058s (-0.7%)	3.228s (+1.8%)	0.672s (-35.1% 🟢)	4.459s (-7.0% 🟢)	1.401s	10	1.04x
▲ Vercel	Express	3.100s (+2.6%)	3.330s (+2.9%)	0.518s (-13.5% 🟢)	4.388s (+1.7%)	1.288s	10	1.06x

🔍 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)	7/8
🐘 Postgres	Next.js (Turbopack)	3/8
▲ Vercel	Nitro	4/8

Fastest World by Framework

Winner determined by most benchmark wins

Framework	🥇 Fastest World	Wins
Express	💻 Local	8/8
Next.js (Turbopack)	💻 Local	8/8
Nitro	💻 Local	8/8

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

[vercel]

🔧 Build Fix:

The OpenAI class is not constructable in the imported module. This is a type error where the code is trying to instantiate the OpenAI class, but the module export doesn't provide a constructor signature.

[TooTallNate]

Enable class serialization in client mode to support passing class instances to workflow functions.

What changed?

• Added support for class serialization transformations in "client" mode
• The plugin now generates necessary imports and registration calls for classes that need serialization in client mode
• When classes are detected that need serialization, the plugin:
  • Imports registerSerializationClass from "workflow/internal/class-serialization"
  • Adds registration calls for each class with a unique class ID
• Updated test outputs to reflect these changes

How to test?

1. Create a class with serialization methods (using WORKFLOW_SERIALIZE and WORKFLOW_DESERIALIZE symbols)
2. Use the class in a client-side context where it's passed to a workflow function
3. Verify that the class is properly serialized and deserialized when passed between client and workflow

Why make this change?

Previously, class serialization was only enabled in workflow mode, which meant that classes couldn't be properly serialized when passed from client code to workflow functions. This change ensures that classes with custom serialization methods work correctly when used as arguments to start(workflow) calls from client code.

[changeset-bot]

🦋 Changeset detected

Latest commit: 1a72c70

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

This PR includes changesets to release 15 packages

Name	Type
@workflow/swc-plugin	Patch
@workflow/astro	Patch
@workflow/builders	Patch
@workflow/cli	Patch
@workflow/nest	Patch
@workflow/next	Patch
@workflow/nitro	Patch
@workflow/rollup	Patch
@workflow/sveltekit	Patch
workflow	Patch
@workflow/world-testing	Patch
@workflow/example-nest	Patch
@workflow/docs-typecheck	Patch
@workflow/nuxt	Patch
@workflow/ai	Patch

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

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

[github-actions]

🧪 E2E Test Results

❌ Some tests failed

Summary

	Passed	Failed	Skipped	Total
✅ ▲ Vercel Production	457	0	38	495
❌ 💻 Local Development	416	2	32	450
✅ 📦 Local Production	418	0	32	450
✅ 🐘 Local Postgres	418	0	32	450
✅ 🪟 Windows	45	0	0	45
❌ 🌍 Community Worlds	31	161	0	192
✅ 📋 Other	123	0	12	135
Total	1908	163	146	2217

❌ Failed Tests

💻 Local Development (2 failed)

astro-stable (2 failed):

• 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

🌍 Community Worlds (161 failed)

mongodb (40 failed):

• addTenWorkflow
• addTenWorkflow
• should work with react rendering in step
• promiseAllWorkflow
• promiseRaceWorkflow
• promiseAnyWorkflow
• readableStreamWorkflow
• hookWorkflow
• webhookWorkflow
• sleepingWorkflow
• nullByteWorkflow
• workflowAndStepMetadataWorkflow
• outputStreamWorkflow
• outputStreamInsideStepWorkflow - getWritable() called inside step functions
• 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
• 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
• pages router addTenWorkflow via pages router
• pages router promiseAllWorkflow via pages router
• pages router sleepingWorkflow via pages router

redis (40 failed):

• addTenWorkflow
• addTenWorkflow
• should work with react rendering in step
• promiseAllWorkflow
• promiseRaceWorkflow
• promiseAnyWorkflow
• readableStreamWorkflow
• hookWorkflow
• webhookWorkflow
• sleepingWorkflow
• nullByteWorkflow
• workflowAndStepMetadataWorkflow
• outputStreamWorkflow
• outputStreamInsideStepWorkflow - getWritable() called inside step functions
• 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
• 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
• pages router addTenWorkflow via pages router
• pages router promiseAllWorkflow via pages router
• pages router sleepingWorkflow via pages router

starter (41 failed):

• addTenWorkflow
• addTenWorkflow
• should work with react rendering in step
• promiseAllWorkflow
• promiseRaceWorkflow
• promiseAnyWorkflow
• readableStreamWorkflow
• hookWorkflow
• webhookWorkflow
• sleepingWorkflow
• nullByteWorkflow
• workflowAndStepMetadataWorkflow
• outputStreamWorkflow
• outputStreamInsideStepWorkflow - getWritable() called inside step functions
• 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 (CLI) - workflow health command reports healthy endpoints
• 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
• pages router addTenWorkflow via pages router
• pages router promiseAllWorkflow via pages router
• pages router sleepingWorkflow via pages router

turso (40 failed):

• addTenWorkflow
• addTenWorkflow
• should work with react rendering in step
• promiseAllWorkflow
• promiseRaceWorkflow
• promiseAnyWorkflow
• readableStreamWorkflow
• hookWorkflow
• webhookWorkflow
• sleepingWorkflow
• nullByteWorkflow
• workflowAndStepMetadataWorkflow
• outputStreamWorkflow
• outputStreamInsideStepWorkflow - getWritable() called inside step functions
• 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
• 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
• 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	41	0	4
✅ example	41	0	4
✅ express	41	0	4
✅ fastify	41	0	4
✅ hono	41	0	4
✅ nextjs-turbopack	44	0	1
✅ nextjs-webpack	44	0	1
✅ nitro	41	0	4
✅ nuxt	41	0	4
✅ sveltekit	41	0	4
✅ vite	41	0	4

❌ 💻 Local Development

App	Passed	Failed	Skipped
❌ astro-stable	39	2	4
✅ express-stable	41	0	4
✅ fastify-stable	41	0	4
✅ hono-stable	41	0	4
✅ nextjs-turbopack-stable	45	0	0
✅ nextjs-webpack-stable	45	0	0
✅ nitro-stable	41	0	4
✅ nuxt-stable	41	0	4
✅ sveltekit-stable	41	0	4
✅ vite-stable	41	0	4

✅ 📦 Local Production

App	Passed	Failed	Skipped
✅ astro-stable	41	0	4
✅ express-stable	41	0	4
✅ fastify-stable	41	0	4
✅ hono-stable	41	0	4
✅ nextjs-turbopack-stable	45	0	0
✅ nextjs-webpack-stable	45	0	0
✅ nitro-stable	41	0	4
✅ nuxt-stable	41	0	4
✅ sveltekit-stable	41	0	4
✅ vite-stable	41	0	4

✅ 🐘 Local Postgres

App	Passed	Failed	Skipped
✅ astro-stable	41	0	4
✅ express-stable	41	0	4
✅ fastify-stable	41	0	4
✅ hono-stable	41	0	4
✅ nextjs-turbopack-stable	45	0	0
✅ nextjs-webpack-stable	45	0	0
✅ nitro-stable	41	0	4
✅ nuxt-stable	41	0	4
✅ sveltekit-stable	41	0	4
✅ vite-stable	41	0	4

✅ 🪟 Windows

App	Passed	Failed	Skipped
✅ nextjs-turbopack	45	0	0

❌ 🌍 Community Worlds

App	Passed	Failed	Skipped
✅ mongodb-dev	3	0	0
❌ mongodb	5	40	0
✅ redis-dev	3	0	0
❌ redis	5	40	0
✅ starter-dev	3	0	0
❌ starter	4	41	0
✅ turso-dev	3	0	0
❌ turso	5	40	0

✅ 📋 Other

App	Passed	Failed	Skipped
✅ e2e-local-dev-nest-stable	41	0	4
✅ e2e-local-postgres-nest-stable	41	0	4
✅ e2e-local-prod-nest-stable	41	0	4

---

📋 View full workflow run

---

❌ Some E2E test jobs failed:

• Vercel Prod: success
• Local Dev: failure
• Local Prod: success
• Local Postgres: success
• Windows: success

Check the workflow run for details.

[vercel]

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

Project	Deployment	Review	Updated (UTC)
example-nextjs-workflow-turbopack	Ready	Preview, Comment	Jan 27, 2026 7:00am
example-nextjs-workflow-webpack	Ready	Preview, Comment	Jan 27, 2026 7:00am
example-workflow	Ready	Preview, Comment	Jan 27, 2026 7:00am
workbench-astro-workflow	Ready	Preview, Comment	Jan 27, 2026 7:00am
workbench-express-workflow	Ready	Preview, Comment	Jan 27, 2026 7:00am
workbench-fastify-workflow	Ready	Preview, Comment	Jan 27, 2026 7:00am
workbench-hono-workflow	Ready	Preview, Comment	Jan 27, 2026 7:00am
workbench-nitro-workflow	Ready	Preview, Comment	Jan 27, 2026 7:00am
workbench-nuxt-workflow	Ready	Preview, Comment	Jan 27, 2026 7:00am
workbench-sveltekit-workflow	Ready	Preview, Comment	Jan 27, 2026 7:00am
workbench-vite-workflow	Ready	Preview, Comment	Jan 27, 2026 7:00am
workflow-docs	Ready	Preview, Comment	Jan 27, 2026 7:00am
workflow-nest	Error		Jan 27, 2026 7:00am

[TooTallNate]

• Enable custom class serialization transformations for "client" mode #860 👈 (View in Graphite)
• main

This stack of pull requests is managed by Graphite. Learn more about stacking.

[Copilot]

Pull request overview

This PR enables custom class serialization transformations for "client" mode in the SWC plugin. Previously, class serialization was only handled in workflow and step modes. This change ensures that classes with custom serialization methods can be properly serialized when passed from client code to workflow functions via start(workflow) calls.

Changes:

• Added import generation for registerSerializationClass in client mode when classes need serialization
• Added registration call generation for classes in client mode (both Module and Script cases)
• Updated test fixtures to reflect the new client mode behavior with serialization imports and registration calls

Reviewed changes

Copilot reviewed 7 out of 7 changed files in this pull request and generated 3 comments.

Show a summary per file

File	Description
packages/swc-plugin-workflow/transform/src/lib.rs	Added logic to generate serialization imports and registration calls for client mode in both Module and Script cases
packages/swc-plugin-workflow/transform/tests/fixture/static-method-step/output-client.js	Added expected import and registration call for MyService class
packages/swc-plugin-workflow/transform/tests/fixture/custom-serialization/output-client.js	Added expected import and registration call for Point class
packages/swc-plugin-workflow/transform/tests/fixture/custom-serialization-local-const/output-client.js	Added expected import and registration calls for Circle, Rectangle, and Triangle classes
packages/swc-plugin-workflow/transform/tests/fixture/custom-serialization-imported/output-client.js	Added expected import and registration calls for Color and Vector classes
packages/swc-plugin-workflow/transform/tests/errors/instance-methods/output-client.js	Added expected import and registration call for TestClass
.changeset/modern-clubs-own.md	Added changeset documenting this patch change

---

💡 Add Copilot custom instructions for smarter, more guided reviews. Learn how to get started.

[ijjk]

Seems good but the deduplication callout from copilot does seem good as well

[github-actions]

📊 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	🥇 Next.js (Turbopack)	0.041s (-16.4% 🟢)	1.019s (~)	0.978s	10	1.00x
💻 Local	Express	0.043s (-1.6%)	1.008s (-1.3%)	0.965s	10	1.04x
💻 Local	Nitro	0.043s (-11.1% 🟢)	1.007s (~)	0.964s	10	1.06x
🐘 Postgres	Express	0.127s (-48.6% 🟢)	1.015s (~)	0.888s	10	3.10x
🐘 Postgres	Nitro	0.162s (-60.9% 🟢)	1.026s (+1.2%)	0.864s	10	3.96x
🐘 Postgres	Next.js (Turbopack)	0.242s (+100.4% 🔺)	1.021s (~)	0.778s	10	5.93x

▲ Production (Vercel)

World	Framework	Workflow Time	Wall Time	Overhead	Samples	vs Fastest
▲ Vercel	🥇 Nitro	0.596s (-11.7% 🟢)	1.698s (+12.3% 🔺)	1.101s	10	1.00x
▲ Vercel	Express	0.629s (-18.0% 🟢)	1.601s (-5.4% 🟢)	0.972s	10	1.05x
▲ Vercel	Next.js (Turbopack)	0.695s (-17.4% 🟢)	1.553s (-9.9% 🟢)	0.858s	10	1.17x

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

workflow with 1 step

💻 Local Development

World	Framework	Workflow Time	Wall Time	Overhead	Samples	vs Fastest
💻 Local	🥇 Next.js (Turbopack)	1.103s (~)	2.012s (~)	0.909s	10	1.00x
💻 Local	Express	1.116s (~)	2.008s (~)	0.892s	10	1.01x
💻 Local	Nitro	1.118s (~)	2.007s (~)	0.889s	10	1.01x
🐘 Postgres	Next.js (Turbopack)	2.254s (+17.5% 🔺)	3.019s (+49.8% 🔺)	0.765s	10	2.04x
🐘 Postgres	Express	2.472s (+17.8% 🔺)	3.013s (~)	0.541s	10	2.24x
🐘 Postgres	Nitro	2.473s (+9.2% 🔺)	3.014s (~)	0.542s	10	2.24x

▲ Production (Vercel)

World	Framework	Workflow Time	Wall Time	Overhead	Samples	vs Fastest
▲ Vercel	🥇 Express	2.730s (-1.8%)	3.744s (+3.0%)	1.013s	10	1.00x
▲ Vercel	Nitro	2.874s (~)	3.779s (+4.6%)	0.905s	10	1.05x
▲ Vercel	Next.js (Turbopack)	2.952s (+1.5%)	3.663s (-0.7%)	0.711s	10	1.08x

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

workflow with 10 sequential steps

💻 Local Development

World	Framework	Workflow Time	Wall Time	Overhead	Samples	vs Fastest
💻 Local	🥇 Next.js (Turbopack)	10.716s (~)	11.018s (~)	0.302s	5	1.00x
💻 Local	Nitro	10.841s (~)	11.014s (~)	0.173s	5	1.01x
💻 Local	Express	10.852s (~)	11.013s (~)	0.161s	5	1.01x
🐘 Postgres	Nitro	20.292s (+0.6%)	21.041s (~)	0.750s	5	1.89x
🐘 Postgres	Express	20.310s (+30.5% 🔺)	21.037s (+31.2% 🔺)	0.726s	5	1.90x
🐘 Postgres	Next.js (Turbopack)	20.354s (+40.4% 🔺)	21.043s (+39.9% 🔺)	0.689s	5	1.90x

▲ Production (Vercel)

World	Framework	Workflow Time	Wall Time	Overhead	Samples	vs Fastest
▲ Vercel	🥇 Nitro	22.236s (-6.6% 🟢)	23.066s (-5.8% 🟢)	0.830s	5	1.00x
▲ Vercel	Express	22.515s (-6.9% 🟢)	23.414s (-6.1% 🟢)	0.898s	5	1.01x
▲ Vercel	Next.js (Turbopack)	22.838s (~)	23.452s (-1.4%)	0.614s	5	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
💻 Local	🥇 Next.js (Turbopack)	1.389s (~)	2.012s (~)	0.622s	15	1.00x
💻 Local	Nitro	1.413s (~)	2.007s (~)	0.594s	15	1.02x
💻 Local	Express	1.414s (-0.8%)	2.007s (~)	0.593s	15	1.02x
🐘 Postgres	Next.js (Turbopack)	2.200s (+3.3%)	2.853s (+5.3% 🔺)	0.653s	11	1.58x
🐘 Postgres	Nitro	2.305s (-4.9%)	2.678s (-11.0% 🟢)	0.373s	12	1.66x
🐘 Postgres	Express	2.515s (+21.3% 🔺)	3.014s (+16.0% 🔺)	0.499s	10	1.81x

▲ Production (Vercel)

World	Framework	Workflow Time	Wall Time	Overhead	Samples	vs Fastest
▲ Vercel	🥇 Next.js (Turbopack)	3.000s (-3.5%)	3.773s (-5.5% 🟢)	0.773s	8	1.00x
▲ Vercel	Nitro	3.406s (+7.1% 🔺)	4.360s (+11.9% 🔺)	0.954s	7	1.14x
▲ Vercel	Express	3.551s (+21.7% 🔺)	4.414s (+16.5% 🔺)	0.863s	7	1.18x

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

Promise.all with 25 concurrent steps

💻 Local Development

World	Framework	Workflow Time	Wall Time	Overhead	Samples	vs Fastest
💻 Local	🥇 Next.js (Turbopack)	2.472s (~)	3.066s (-4.3%)	0.594s	10	1.00x
💻 Local	Express	2.502s (-2.0%)	3.029s (+0.5%)	0.527s	10	1.01x
💻 Local	Nitro	2.510s (-2.1%)	3.026s (~)	0.515s	10	1.02x
🐘 Postgres	Express	7.934s (-20.5% 🟢)	8.305s (-20.5% 🟢)	0.371s	4	3.21x
🐘 Postgres	Nitro	8.839s (+18.5% 🔺)	9.274s (+14.9% 🔺)	0.435s	4	3.58x
🐘 Postgres	Next.js (Turbopack)	11.559s (-0.8%)	12.037s (-0.7%)	0.478s	3	4.68x

▲ Production (Vercel)

World	Framework	Workflow Time	Wall Time	Overhead	Samples	vs Fastest
▲ Vercel	🥇 Next.js (Turbopack)	3.235s (-6.5% 🟢)	4.052s (-0.7%)	0.817s	8	1.00x
▲ Vercel	Express	3.374s (+2.4%)	4.168s (+2.8%)	0.795s	8	1.04x
▲ Vercel	Nitro	3.535s (+15.7% 🔺)	4.228s (+10.6% 🔺)	0.694s	8	1.09x

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

Promise.race with 10 concurrent steps

💻 Local Development

World	Framework	Workflow Time	Wall Time	Overhead	Samples	vs Fastest
💻 Local	🥇 Nitro	1.409s (-2.7%)	2.007s (~)	0.598s	15	1.00x
💻 Local	Next.js (Turbopack)	1.427s (+1.0%)	2.013s (~)	0.586s	15	1.01x
💻 Local	Express	1.434s (~)	2.006s (~)	0.572s	15	1.02x
🐘 Postgres	Nitro	1.967s (-8.0% 🟢)	2.477s (-4.7%)	0.511s	13	1.40x
🐘 Postgres	Express	2.061s (+14.5% 🔺)	2.528s (+13.3% 🔺)	0.467s	12	1.46x
🐘 Postgres	Next.js (Turbopack)	2.299s (-2.5%)	2.746s (-9.2% 🟢)	0.447s	11	1.63x

▲ Production (Vercel)

World	Framework	Workflow Time	Wall Time	Overhead	Samples	vs Fastest
▲ Vercel	🥇 Nitro	2.838s (+1.0%)	3.792s (+3.6%)	0.953s	8	1.00x
▲ Vercel	Express	2.853s (+0.9%)	3.886s (+5.3% 🔺)	1.033s	8	1.01x
▲ Vercel	Next.js (Turbopack)	3.017s (+5.7% 🔺)	4.024s (+9.6% 🔺)	1.007s	8	1.06x

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

Promise.race with 25 concurrent steps

💻 Local Development

World	Framework	Workflow Time	Wall Time	Overhead	Samples	vs Fastest
💻 Local	🥇 Next.js (Turbopack)	2.536s (~)	3.102s (+1.6%)	0.566s	10	1.00x
💻 Local	Express	2.568s (-2.8%)	3.022s (~)	0.454s	10	1.01x
💻 Local	Nitro	2.596s (-0.5%)	3.022s (~)	0.427s	10	1.02x
🐘 Postgres	Nitro	11.622s (-3.4%)	12.050s (-2.8%)	0.428s	3	4.58x
🐘 Postgres	Express	12.974s (+6.7% 🔺)	13.022s (+2.5%)	0.048s	3	5.12x
🐘 Postgres	Next.js (Turbopack)	13.121s (-5.6% 🟢)	13.705s (-4.6%)	0.584s	3	5.17x

▲ Production (Vercel)

World	Framework	Workflow Time	Wall Time	Overhead	Samples	vs Fastest
▲ Vercel	🥇 Nitro	3.089s (-21.8% 🟢)	3.948s (-18.8% 🟢)	0.859s	8	1.00x
▲ Vercel	Next.js (Turbopack)	3.263s (+4.6%)	4.032s (+6.9% 🔺)	0.769s	8	1.06x
▲ Vercel	Express	3.657s (+2.4%)	4.312s (-0.8%)	0.655s	7	1.18x

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

Stream Benchmarks(includes TTFB metrics)

workflow with stream

💻 Local Development

World	Framework	Workflow Time	TTFB	Slurp	Wall Time	Overhead	Samples	vs Fastest
💻 Local	🥇 Next.js (Turbopack)	0.144s (+1.6%)	1.004s (~)	0.016s (-12.2% 🟢)	1.027s (~)	0.884s	10	1.00x
💻 Local	Express	0.184s (-0.7%)	0.992s (~)	0.018s (+19.9% 🔺)	1.024s (~)	0.841s	10	1.28x
💻 Local	Nitro	0.188s (-0.6%)	0.993s (~)	0.015s (-2.6%)	1.022s (~)	0.834s	10	1.31x
🐘 Postgres	Next.js (Turbopack)	1.304s (+107.0% 🔺)	2.040s (+109.8% 🔺)	0.000s (NaN%)	2.120s (+108.6% 🔺)	0.816s	10	9.07x
🐘 Postgres	Nitro	1.451s (-41.4% 🟢)	2.266s (-11.6% 🟢)	0.000s (-100.0% 🟢)	2.314s (-23.2% 🟢)	0.863s	10	10.10x
🐘 Postgres	Express	2.104s (+65.2% 🔺)	2.936s (+66.6% 🔺)	0.000s (NaN%)	3.016s (+49.7% 🔺)	0.911s	10	14.64x

▲ Production (Vercel)

World	Framework	Workflow Time	TTFB	Slurp	Wall Time	Overhead	Samples	vs Fastest
▲ Vercel	🥇 Next.js (Turbopack)	2.932s (-4.8%)	3.245s (+2.3%)	0.537s (-33.6% 🟢)	4.267s (-5.6% 🟢)	1.335s	10	1.00x
▲ Vercel	Nitro	3.058s (-0.7%)	3.228s (+1.8%)	0.672s (-35.1% 🟢)	4.459s (-7.0% 🟢)	1.401s	10	1.04x
▲ Vercel	Express	3.100s (+2.6%)	3.330s (+2.9%)	0.518s (-13.5% 🟢)	4.388s (+1.7%)	1.288s	10	1.06x

🔍 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)	7/8
🐘 Postgres	Next.js (Turbopack)	3/8
▲ Vercel	Nitro	4/8

Fastest World by Framework

Winner determined by most benchmark wins

Framework	🥇 Fastest World	Wins
Express	💻 Local	8/8
Next.js (Turbopack)	💻 Local	8/8
Nitro	💻 Local	8/8

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

[vercel]

🔧 Build Fix:

The OpenAI class is not constructable in the imported module. This is a type error where the code is trying to instantiate the OpenAI class, but the module export doesn't provide a constructor signature.

[TooTallNate]

Enable class serialization in client mode to support passing class instances to workflow functions.

What changed?

• Added support for class serialization transformations in "client" mode
• The plugin now generates necessary imports and registration calls for classes that need serialization in client mode
• When classes are detected that need serialization, the plugin:
  • Imports registerSerializationClass from "workflow/internal/class-serialization"
  • Adds registration calls for each class with a unique class ID
• Updated test outputs to reflect these changes

How to test?

1. Create a class with serialization methods (using WORKFLOW_SERIALIZE and WORKFLOW_DESERIALIZE symbols)
2. Use the class in a client-side context where it's passed to a workflow function
3. Verify that the class is properly serialized and deserialized when passed between client and workflow

Why make this change?

Previously, class serialization was only enabled in workflow mode, which meant that classes couldn't be properly serialized when passed from client code to workflow functions. This change ensures that classes with custom serialization methods work correctly when used as arguments to start(workflow) calls from client code.

[changeset-bot]

🦋 Changeset detected

Latest commit: 1a72c70

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

This PR includes changesets to release 15 packages

Name	Type
@workflow/swc-plugin	Patch
@workflow/astro	Patch
@workflow/builders	Patch
@workflow/cli	Patch
@workflow/nest	Patch
@workflow/next	Patch
@workflow/nitro	Patch
@workflow/rollup	Patch
@workflow/sveltekit	Patch
workflow	Patch
@workflow/world-testing	Patch
@workflow/example-nest	Patch
@workflow/docs-typecheck	Patch
@workflow/nuxt	Patch
@workflow/ai	Patch

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

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

[github-actions]

🧪 E2E Test Results

❌ Some tests failed

Summary

	Passed	Failed	Skipped	Total
✅ ▲ Vercel Production	457	0	38	495
❌ 💻 Local Development	416	2	32	450
✅ 📦 Local Production	418	0	32	450
✅ 🐘 Local Postgres	418	0	32	450
✅ 🪟 Windows	45	0	0	45
❌ 🌍 Community Worlds	31	161	0	192
✅ 📋 Other	123	0	12	135
Total	1908	163	146	2217

❌ Failed Tests

💻 Local Development (2 failed)

astro-stable (2 failed):

• 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

🌍 Community Worlds (161 failed)

mongodb (40 failed):

• addTenWorkflow
• addTenWorkflow
• should work with react rendering in step
• promiseAllWorkflow
• promiseRaceWorkflow
• promiseAnyWorkflow
• readableStreamWorkflow
• hookWorkflow
• webhookWorkflow
• sleepingWorkflow
• nullByteWorkflow
• workflowAndStepMetadataWorkflow
• outputStreamWorkflow
• outputStreamInsideStepWorkflow - getWritable() called inside step functions
• 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
• 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
• pages router addTenWorkflow via pages router
• pages router promiseAllWorkflow via pages router
• pages router sleepingWorkflow via pages router

redis (40 failed):

• addTenWorkflow
• addTenWorkflow
• should work with react rendering in step
• promiseAllWorkflow
• promiseRaceWorkflow
• promiseAnyWorkflow
• readableStreamWorkflow
• hookWorkflow
• webhookWorkflow
• sleepingWorkflow
• nullByteWorkflow
• workflowAndStepMetadataWorkflow
• outputStreamWorkflow
• outputStreamInsideStepWorkflow - getWritable() called inside step functions
• 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
• 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
• pages router addTenWorkflow via pages router
• pages router promiseAllWorkflow via pages router
• pages router sleepingWorkflow via pages router

starter (41 failed):

• addTenWorkflow
• addTenWorkflow
• should work with react rendering in step
• promiseAllWorkflow
• promiseRaceWorkflow
• promiseAnyWorkflow
• readableStreamWorkflow
• hookWorkflow
• webhookWorkflow
• sleepingWorkflow
• nullByteWorkflow
• workflowAndStepMetadataWorkflow
• outputStreamWorkflow
• outputStreamInsideStepWorkflow - getWritable() called inside step functions
• 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 (CLI) - workflow health command reports healthy endpoints
• 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
• pages router addTenWorkflow via pages router
• pages router promiseAllWorkflow via pages router
• pages router sleepingWorkflow via pages router

turso (40 failed):

• addTenWorkflow
• addTenWorkflow
• should work with react rendering in step
• promiseAllWorkflow
• promiseRaceWorkflow
• promiseAnyWorkflow
• readableStreamWorkflow
• hookWorkflow
• webhookWorkflow
• sleepingWorkflow
• nullByteWorkflow
• workflowAndStepMetadataWorkflow
• outputStreamWorkflow
• outputStreamInsideStepWorkflow - getWritable() called inside step functions
• 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
• 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
• 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	41	0	4
✅ example	41	0	4
✅ express	41	0	4
✅ fastify	41	0	4
✅ hono	41	0	4
✅ nextjs-turbopack	44	0	1
✅ nextjs-webpack	44	0	1
✅ nitro	41	0	4
✅ nuxt	41	0	4
✅ sveltekit	41	0	4
✅ vite	41	0	4

❌ 💻 Local Development

App	Passed	Failed	Skipped
❌ astro-stable	39	2	4
✅ express-stable	41	0	4
✅ fastify-stable	41	0	4
✅ hono-stable	41	0	4
✅ nextjs-turbopack-stable	45	0	0
✅ nextjs-webpack-stable	45	0	0
✅ nitro-stable	41	0	4
✅ nuxt-stable	41	0	4
✅ sveltekit-stable	41	0	4
✅ vite-stable	41	0	4

✅ 📦 Local Production

App	Passed	Failed	Skipped
✅ astro-stable	41	0	4
✅ express-stable	41	0	4
✅ fastify-stable	41	0	4
✅ hono-stable	41	0	4
✅ nextjs-turbopack-stable	45	0	0
✅ nextjs-webpack-stable	45	0	0
✅ nitro-stable	41	0	4
✅ nuxt-stable	41	0	4
✅ sveltekit-stable	41	0	4
✅ vite-stable	41	0	4

✅ 🐘 Local Postgres

App	Passed	Failed	Skipped
✅ astro-stable	41	0	4
✅ express-stable	41	0	4
✅ fastify-stable	41	0	4
✅ hono-stable	41	0	4
✅ nextjs-turbopack-stable	45	0	0
✅ nextjs-webpack-stable	45	0	0
✅ nitro-stable	41	0	4
✅ nuxt-stable	41	0	4
✅ sveltekit-stable	41	0	4
✅ vite-stable	41	0	4

✅ 🪟 Windows

App	Passed	Failed	Skipped
✅ nextjs-turbopack	45	0	0

❌ 🌍 Community Worlds

App	Passed	Failed	Skipped
✅ mongodb-dev	3	0	0
❌ mongodb	5	40	0
✅ redis-dev	3	0	0
❌ redis	5	40	0
✅ starter-dev	3	0	0
❌ starter	4	41	0
✅ turso-dev	3	0	0
❌ turso	5	40	0

✅ 📋 Other

App	Passed	Failed	Skipped
✅ e2e-local-dev-nest-stable	41	0	4
✅ e2e-local-postgres-nest-stable	41	0	4
✅ e2e-local-prod-nest-stable	41	0	4

---

📋 View full workflow run

---

❌ Some E2E test jobs failed:

• Vercel Prod: success
• Local Dev: failure
• Local Prod: success
• Local Postgres: success
• Windows: success

Check the workflow run for details.

[vercel]

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

Project	Deployment	Review	Updated (UTC)
example-nextjs-workflow-turbopack	Ready	Preview, Comment	Jan 27, 2026 7:00am
example-nextjs-workflow-webpack	Ready	Preview, Comment	Jan 27, 2026 7:00am
example-workflow	Ready	Preview, Comment	Jan 27, 2026 7:00am
workbench-astro-workflow	Ready	Preview, Comment	Jan 27, 2026 7:00am
workbench-express-workflow	Ready	Preview, Comment	Jan 27, 2026 7:00am
workbench-fastify-workflow	Ready	Preview, Comment	Jan 27, 2026 7:00am
workbench-hono-workflow	Ready	Preview, Comment	Jan 27, 2026 7:00am
workbench-nitro-workflow	Ready	Preview, Comment	Jan 27, 2026 7:00am
workbench-nuxt-workflow	Ready	Preview, Comment	Jan 27, 2026 7:00am
workbench-sveltekit-workflow	Ready	Preview, Comment	Jan 27, 2026 7:00am
workbench-vite-workflow	Ready	Preview, Comment	Jan 27, 2026 7:00am
workflow-docs	Ready	Preview, Comment	Jan 27, 2026 7:00am
workflow-nest	Error		Jan 27, 2026 7:00am

[TooTallNate]

• Enable custom class serialization transformations for "client" mode #860 👈 (View in Graphite)
• main

This stack of pull requests is managed by Graphite. Learn more about stacking.

[Copilot]

Pull request overview

This PR enables custom class serialization transformations for "client" mode in the SWC plugin. Previously, class serialization was only handled in workflow and step modes. This change ensures that classes with custom serialization methods can be properly serialized when passed from client code to workflow functions via start(workflow) calls.

Changes:

• Added import generation for registerSerializationClass in client mode when classes need serialization
• Added registration call generation for classes in client mode (both Module and Script cases)
• Updated test fixtures to reflect the new client mode behavior with serialization imports and registration calls

Reviewed changes

Copilot reviewed 7 out of 7 changed files in this pull request and generated 3 comments.

Show a summary per file

File	Description
packages/swc-plugin-workflow/transform/src/lib.rs	Added logic to generate serialization imports and registration calls for client mode in both Module and Script cases
packages/swc-plugin-workflow/transform/tests/fixture/static-method-step/output-client.js	Added expected import and registration call for MyService class
packages/swc-plugin-workflow/transform/tests/fixture/custom-serialization/output-client.js	Added expected import and registration call for Point class
packages/swc-plugin-workflow/transform/tests/fixture/custom-serialization-local-const/output-client.js	Added expected import and registration calls for Circle, Rectangle, and Triangle classes
packages/swc-plugin-workflow/transform/tests/fixture/custom-serialization-imported/output-client.js	Added expected import and registration calls for Color and Vector classes
packages/swc-plugin-workflow/transform/tests/errors/instance-methods/output-client.js	Added expected import and registration call for TestClass
.changeset/modern-clubs-own.md	Added changeset documenting this patch change

---

💡 Add Copilot custom instructions for smarter, more guided reviews. Learn how to get started.

[ijjk]

Seems good but the deduplication callout from copilot does seem good as well

[github-actions]

📊 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	🥇 Next.js (Turbopack)	0.041s (-16.4% 🟢)	1.019s (~)	0.978s	10	1.00x
💻 Local	Express	0.043s (-1.6%)	1.008s (-1.3%)	0.965s	10	1.04x
💻 Local	Nitro	0.043s (-11.1% 🟢)	1.007s (~)	0.964s	10	1.06x
🐘 Postgres	Express	0.127s (-48.6% 🟢)	1.015s (~)	0.888s	10	3.10x
🐘 Postgres	Nitro	0.162s (-60.9% 🟢)	1.026s (+1.2%)	0.864s	10	3.96x
🐘 Postgres	Next.js (Turbopack)	0.242s (+100.4% 🔺)	1.021s (~)	0.778s	10	5.93x

▲ Production (Vercel)

World	Framework	Workflow Time	Wall Time	Overhead	Samples	vs Fastest
▲ Vercel	🥇 Nitro	0.596s (-11.7% 🟢)	1.698s (+12.3% 🔺)	1.101s	10	1.00x
▲ Vercel	Express	0.629s (-18.0% 🟢)	1.601s (-5.4% 🟢)	0.972s	10	1.05x
▲ Vercel	Next.js (Turbopack)	0.695s (-17.4% 🟢)	1.553s (-9.9% 🟢)	0.858s	10	1.17x

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

workflow with 1 step

💻 Local Development

World	Framework	Workflow Time	Wall Time	Overhead	Samples	vs Fastest
💻 Local	🥇 Next.js (Turbopack)	1.103s (~)	2.012s (~)	0.909s	10	1.00x
💻 Local	Express	1.116s (~)	2.008s (~)	0.892s	10	1.01x
💻 Local	Nitro	1.118s (~)	2.007s (~)	0.889s	10	1.01x
🐘 Postgres	Next.js (Turbopack)	2.254s (+17.5% 🔺)	3.019s (+49.8% 🔺)	0.765s	10	2.04x
🐘 Postgres	Express	2.472s (+17.8% 🔺)	3.013s (~)	0.541s	10	2.24x
🐘 Postgres	Nitro	2.473s (+9.2% 🔺)	3.014s (~)	0.542s	10	2.24x

▲ Production (Vercel)

World	Framework	Workflow Time	Wall Time	Overhead	Samples	vs Fastest
▲ Vercel	🥇 Express	2.730s (-1.8%)	3.744s (+3.0%)	1.013s	10	1.00x
▲ Vercel	Nitro	2.874s (~)	3.779s (+4.6%)	0.905s	10	1.05x
▲ Vercel	Next.js (Turbopack)	2.952s (+1.5%)	3.663s (-0.7%)	0.711s	10	1.08x

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

workflow with 10 sequential steps

💻 Local Development

World	Framework	Workflow Time	Wall Time	Overhead	Samples	vs Fastest
💻 Local	🥇 Next.js (Turbopack)	10.716s (~)	11.018s (~)	0.302s	5	1.00x
💻 Local	Nitro	10.841s (~)	11.014s (~)	0.173s	5	1.01x
💻 Local	Express	10.852s (~)	11.013s (~)	0.161s	5	1.01x
🐘 Postgres	Nitro	20.292s (+0.6%)	21.041s (~)	0.750s	5	1.89x
🐘 Postgres	Express	20.310s (+30.5% 🔺)	21.037s (+31.2% 🔺)	0.726s	5	1.90x
🐘 Postgres	Next.js (Turbopack)	20.354s (+40.4% 🔺)	21.043s (+39.9% 🔺)	0.689s	5	1.90x

▲ Production (Vercel)

World	Framework	Workflow Time	Wall Time	Overhead	Samples	vs Fastest
▲ Vercel	🥇 Nitro	22.236s (-6.6% 🟢)	23.066s (-5.8% 🟢)	0.830s	5	1.00x
▲ Vercel	Express	22.515s (-6.9% 🟢)	23.414s (-6.1% 🟢)	0.898s	5	1.01x
▲ Vercel	Next.js (Turbopack)	22.838s (~)	23.452s (-1.4%)	0.614s	5	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
💻 Local	🥇 Next.js (Turbopack)	1.389s (~)	2.012s (~)	0.622s	15	1.00x
💻 Local	Nitro	1.413s (~)	2.007s (~)	0.594s	15	1.02x
💻 Local	Express	1.414s (-0.8%)	2.007s (~)	0.593s	15	1.02x
🐘 Postgres	Next.js (Turbopack)	2.200s (+3.3%)	2.853s (+5.3% 🔺)	0.653s	11	1.58x
🐘 Postgres	Nitro	2.305s (-4.9%)	2.678s (-11.0% 🟢)	0.373s	12	1.66x
🐘 Postgres	Express	2.515s (+21.3% 🔺)	3.014s (+16.0% 🔺)	0.499s	10	1.81x

▲ Production (Vercel)

World	Framework	Workflow Time	Wall Time	Overhead	Samples	vs Fastest
▲ Vercel	🥇 Next.js (Turbopack)	3.000s (-3.5%)	3.773s (-5.5% 🟢)	0.773s	8	1.00x
▲ Vercel	Nitro	3.406s (+7.1% 🔺)	4.360s (+11.9% 🔺)	0.954s	7	1.14x
▲ Vercel	Express	3.551s (+21.7% 🔺)	4.414s (+16.5% 🔺)	0.863s	7	1.18x

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

Promise.all with 25 concurrent steps

💻 Local Development

World	Framework	Workflow Time	Wall Time	Overhead	Samples	vs Fastest
💻 Local	🥇 Next.js (Turbopack)	2.472s (~)	3.066s (-4.3%)	0.594s	10	1.00x
💻 Local	Express	2.502s (-2.0%)	3.029s (+0.5%)	0.527s	10	1.01x
💻 Local	Nitro	2.510s (-2.1%)	3.026s (~)	0.515s	10	1.02x
🐘 Postgres	Express	7.934s (-20.5% 🟢)	8.305s (-20.5% 🟢)	0.371s	4	3.21x
🐘 Postgres	Nitro	8.839s (+18.5% 🔺)	9.274s (+14.9% 🔺)	0.435s	4	3.58x
🐘 Postgres	Next.js (Turbopack)	11.559s (-0.8%)	12.037s (-0.7%)	0.478s	3	4.68x

▲ Production (Vercel)

World	Framework	Workflow Time	Wall Time	Overhead	Samples	vs Fastest
▲ Vercel	🥇 Next.js (Turbopack)	3.235s (-6.5% 🟢)	4.052s (-0.7%)	0.817s	8	1.00x
▲ Vercel	Express	3.374s (+2.4%)	4.168s (+2.8%)	0.795s	8	1.04x
▲ Vercel	Nitro	3.535s (+15.7% 🔺)	4.228s (+10.6% 🔺)	0.694s	8	1.09x

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

Promise.race with 10 concurrent steps

💻 Local Development

World	Framework	Workflow Time	Wall Time	Overhead	Samples	vs Fastest
💻 Local	🥇 Nitro	1.409s (-2.7%)	2.007s (~)	0.598s	15	1.00x
💻 Local	Next.js (Turbopack)	1.427s (+1.0%)	2.013s (~)	0.586s	15	1.01x
💻 Local	Express	1.434s (~)	2.006s (~)	0.572s	15	1.02x
🐘 Postgres	Nitro	1.967s (-8.0% 🟢)	2.477s (-4.7%)	0.511s	13	1.40x
🐘 Postgres	Express	2.061s (+14.5% 🔺)	2.528s (+13.3% 🔺)	0.467s	12	1.46x
🐘 Postgres	Next.js (Turbopack)	2.299s (-2.5%)	2.746s (-9.2% 🟢)	0.447s	11	1.63x

▲ Production (Vercel)

World	Framework	Workflow Time	Wall Time	Overhead	Samples	vs Fastest
▲ Vercel	🥇 Nitro	2.838s (+1.0%)	3.792s (+3.6%)	0.953s	8	1.00x
▲ Vercel	Express	2.853s (+0.9%)	3.886s (+5.3% 🔺)	1.033s	8	1.01x
▲ Vercel	Next.js (Turbopack)	3.017s (+5.7% 🔺)	4.024s (+9.6% 🔺)	1.007s	8	1.06x

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

Promise.race with 25 concurrent steps

💻 Local Development

World	Framework	Workflow Time	Wall Time	Overhead	Samples	vs Fastest
💻 Local	🥇 Next.js (Turbopack)	2.536s (~)	3.102s (+1.6%)	0.566s	10	1.00x
💻 Local	Express	2.568s (-2.8%)	3.022s (~)	0.454s	10	1.01x
💻 Local	Nitro	2.596s (-0.5%)	3.022s (~)	0.427s	10	1.02x
🐘 Postgres	Nitro	11.622s (-3.4%)	12.050s (-2.8%)	0.428s	3	4.58x
🐘 Postgres	Express	12.974s (+6.7% 🔺)	13.022s (+2.5%)	0.048s	3	5.12x
🐘 Postgres	Next.js (Turbopack)	13.121s (-5.6% 🟢)	13.705s (-4.6%)	0.584s	3	5.17x

▲ Production (Vercel)

World	Framework	Workflow Time	Wall Time	Overhead	Samples	vs Fastest
▲ Vercel	🥇 Nitro	3.089s (-21.8% 🟢)	3.948s (-18.8% 🟢)	0.859s	8	1.00x
▲ Vercel	Next.js (Turbopack)	3.263s (+4.6%)	4.032s (+6.9% 🔺)	0.769s	8	1.06x
▲ Vercel	Express	3.657s (+2.4%)	4.312s (-0.8%)	0.655s	7	1.18x

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

Stream Benchmarks(includes TTFB metrics)

workflow with stream

💻 Local Development

World	Framework	Workflow Time	TTFB	Slurp	Wall Time	Overhead	Samples	vs Fastest
💻 Local	🥇 Next.js (Turbopack)	0.144s (+1.6%)	1.004s (~)	0.016s (-12.2% 🟢)	1.027s (~)	0.884s	10	1.00x
💻 Local	Express	0.184s (-0.7%)	0.992s (~)	0.018s (+19.9% 🔺)	1.024s (~)	0.841s	10	1.28x
💻 Local	Nitro	0.188s (-0.6%)	0.993s (~)	0.015s (-2.6%)	1.022s (~)	0.834s	10	1.31x
🐘 Postgres	Next.js (Turbopack)	1.304s (+107.0% 🔺)	2.040s (+109.8% 🔺)	0.000s (NaN%)	2.120s (+108.6% 🔺)	0.816s	10	9.07x
🐘 Postgres	Nitro	1.451s (-41.4% 🟢)	2.266s (-11.6% 🟢)	0.000s (-100.0% 🟢)	2.314s (-23.2% 🟢)	0.863s	10	10.10x
🐘 Postgres	Express	2.104s (+65.2% 🔺)	2.936s (+66.6% 🔺)	0.000s (NaN%)	3.016s (+49.7% 🔺)	0.911s	10	14.64x

▲ Production (Vercel)

World	Framework	Workflow Time	TTFB	Slurp	Wall Time	Overhead	Samples	vs Fastest
▲ Vercel	🥇 Next.js (Turbopack)	2.932s (-4.8%)	3.245s (+2.3%)	0.537s (-33.6% 🟢)	4.267s (-5.6% 🟢)	1.335s	10	1.00x
▲ Vercel	Nitro	3.058s (-0.7%)	3.228s (+1.8%)	0.672s (-35.1% 🟢)	4.459s (-7.0% 🟢)	1.401s	10	1.04x
▲ Vercel	Express	3.100s (+2.6%)	3.330s (+2.9%)	0.518s (-13.5% 🟢)	4.388s (+1.7%)	1.288s	10	1.06x

🔍 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)	7/8
🐘 Postgres	Next.js (Turbopack)	3/8
▲ Vercel	Nitro	4/8

Fastest World by Framework

Winner determined by most benchmark wins

Framework	🥇 Fastest World	Wins
Express	💻 Local	8/8
Next.js (Turbopack)	💻 Local	8/8
Nitro	💻 Local	8/8

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

[vercel]

🔧 Build Fix:

The OpenAI class is not constructable in the imported module. This is a type error where the code is trying to instantiate the OpenAI class, but the module export doesn't provide a constructor signature.

[TooTallNate]

Enable class serialization in client mode to support passing class instances to workflow functions.

What changed?

• Added support for class serialization transformations in "client" mode
• The plugin now generates necessary imports and registration calls for classes that need serialization in client mode
• When classes are detected that need serialization, the plugin:
  • Imports registerSerializationClass from "workflow/internal/class-serialization"
  • Adds registration calls for each class with a unique class ID
• Updated test outputs to reflect these changes

How to test?

1. Create a class with serialization methods (using WORKFLOW_SERIALIZE and WORKFLOW_DESERIALIZE symbols)
2. Use the class in a client-side context where it's passed to a workflow function
3. Verify that the class is properly serialized and deserialized when passed between client and workflow

Why make this change?

Previously, class serialization was only enabled in workflow mode, which meant that classes couldn't be properly serialized when passed from client code to workflow functions. This change ensures that classes with custom serialization methods work correctly when used as arguments to start(workflow) calls from client code.

[changeset-bot]

🦋 Changeset detected

Latest commit: 1a72c70

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

This PR includes changesets to release 15 packages

Name	Type
@workflow/swc-plugin	Patch
@workflow/astro	Patch
@workflow/builders	Patch
@workflow/cli	Patch
@workflow/nest	Patch
@workflow/next	Patch
@workflow/nitro	Patch
@workflow/rollup	Patch
@workflow/sveltekit	Patch
workflow	Patch
@workflow/world-testing	Patch
@workflow/example-nest	Patch
@workflow/docs-typecheck	Patch
@workflow/nuxt	Patch
@workflow/ai	Patch

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

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

[github-actions]

🧪 E2E Test Results

❌ Some tests failed

Summary

	Passed	Failed	Skipped	Total
✅ ▲ Vercel Production	457	0	38	495
❌ 💻 Local Development	416	2	32	450
✅ 📦 Local Production	418	0	32	450
✅ 🐘 Local Postgres	418	0	32	450
✅ 🪟 Windows	45	0	0	45
❌ 🌍 Community Worlds	31	161	0	192
✅ 📋 Other	123	0	12	135
Total	1908	163	146	2217

❌ Failed Tests

💻 Local Development (2 failed)

astro-stable (2 failed):

• 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

🌍 Community Worlds (161 failed)

mongodb (40 failed):

• addTenWorkflow
• addTenWorkflow
• should work with react rendering in step
• promiseAllWorkflow
• promiseRaceWorkflow
• promiseAnyWorkflow
• readableStreamWorkflow
• hookWorkflow
• webhookWorkflow
• sleepingWorkflow
• nullByteWorkflow
• workflowAndStepMetadataWorkflow
• outputStreamWorkflow
• outputStreamInsideStepWorkflow - getWritable() called inside step functions
• 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
• 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
• pages router addTenWorkflow via pages router
• pages router promiseAllWorkflow via pages router
• pages router sleepingWorkflow via pages router

redis (40 failed):

• addTenWorkflow
• addTenWorkflow
• should work with react rendering in step
• promiseAllWorkflow
• promiseRaceWorkflow
• promiseAnyWorkflow
• readableStreamWorkflow
• hookWorkflow
• webhookWorkflow
• sleepingWorkflow
• nullByteWorkflow
• workflowAndStepMetadataWorkflow
• outputStreamWorkflow
• outputStreamInsideStepWorkflow - getWritable() called inside step functions
• 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
• 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
• pages router addTenWorkflow via pages router
• pages router promiseAllWorkflow via pages router
• pages router sleepingWorkflow via pages router

starter (41 failed):

• addTenWorkflow
• addTenWorkflow
• should work with react rendering in step
• promiseAllWorkflow
• promiseRaceWorkflow
• promiseAnyWorkflow
• readableStreamWorkflow
• hookWorkflow
• webhookWorkflow
• sleepingWorkflow
• nullByteWorkflow
• workflowAndStepMetadataWorkflow
• outputStreamWorkflow
• outputStreamInsideStepWorkflow - getWritable() called inside step functions
• 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 (CLI) - workflow health command reports healthy endpoints
• 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
• pages router addTenWorkflow via pages router
• pages router promiseAllWorkflow via pages router
• pages router sleepingWorkflow via pages router

turso (40 failed):

• addTenWorkflow
• addTenWorkflow
• should work with react rendering in step
• promiseAllWorkflow
• promiseRaceWorkflow
• promiseAnyWorkflow
• readableStreamWorkflow
• hookWorkflow
• webhookWorkflow
• sleepingWorkflow
• nullByteWorkflow
• workflowAndStepMetadataWorkflow
• outputStreamWorkflow
• outputStreamInsideStepWorkflow - getWritable() called inside step functions
• 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
• 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
• 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	41	0	4
✅ example	41	0	4
✅ express	41	0	4
✅ fastify	41	0	4
✅ hono	41	0	4
✅ nextjs-turbopack	44	0	1
✅ nextjs-webpack	44	0	1
✅ nitro	41	0	4
✅ nuxt	41	0	4
✅ sveltekit	41	0	4
✅ vite	41	0	4

❌ 💻 Local Development

App	Passed	Failed	Skipped
❌ astro-stable	39	2	4
✅ express-stable	41	0	4
✅ fastify-stable	41	0	4
✅ hono-stable	41	0	4
✅ nextjs-turbopack-stable	45	0	0
✅ nextjs-webpack-stable	45	0	0
✅ nitro-stable	41	0	4
✅ nuxt-stable	41	0	4
✅ sveltekit-stable	41	0	4
✅ vite-stable	41	0	4

✅ 📦 Local Production

App	Passed	Failed	Skipped
✅ astro-stable	41	0	4
✅ express-stable	41	0	4
✅ fastify-stable	41	0	4
✅ hono-stable	41	0	4
✅ nextjs-turbopack-stable	45	0	0
✅ nextjs-webpack-stable	45	0	0
✅ nitro-stable	41	0	4
✅ nuxt-stable	41	0	4
✅ sveltekit-stable	41	0	4
✅ vite-stable	41	0	4

✅ 🐘 Local Postgres

App	Passed	Failed	Skipped
✅ astro-stable	41	0	4
✅ express-stable	41	0	4
✅ fastify-stable	41	0	4
✅ hono-stable	41	0	4
✅ nextjs-turbopack-stable	45	0	0
✅ nextjs-webpack-stable	45	0	0
✅ nitro-stable	41	0	4
✅ nuxt-stable	41	0	4
✅ sveltekit-stable	41	0	4
✅ vite-stable	41	0	4

✅ 🪟 Windows

App	Passed	Failed	Skipped
✅ nextjs-turbopack	45	0	0

❌ 🌍 Community Worlds

App	Passed	Failed	Skipped
✅ mongodb-dev	3	0	0
❌ mongodb	5	40	0
✅ redis-dev	3	0	0
❌ redis	5	40	0
✅ starter-dev	3	0	0
❌ starter	4	41	0
✅ turso-dev	3	0	0
❌ turso	5	40	0

✅ 📋 Other

App	Passed	Failed	Skipped
✅ e2e-local-dev-nest-stable	41	0	4
✅ e2e-local-postgres-nest-stable	41	0	4
✅ e2e-local-prod-nest-stable	41	0	4

---

📋 View full workflow run

---

❌ Some E2E test jobs failed:

• Vercel Prod: success
• Local Dev: failure
• Local Prod: success
• Local Postgres: success
• Windows: success

Check the workflow run for details.

[vercel]

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

Project	Deployment	Review	Updated (UTC)
example-nextjs-workflow-turbopack	Ready	Preview, Comment	Jan 27, 2026 7:00am
example-nextjs-workflow-webpack	Ready	Preview, Comment	Jan 27, 2026 7:00am
example-workflow	Ready	Preview, Comment	Jan 27, 2026 7:00am
workbench-astro-workflow	Ready	Preview, Comment	Jan 27, 2026 7:00am
workbench-express-workflow	Ready	Preview, Comment	Jan 27, 2026 7:00am
workbench-fastify-workflow	Ready	Preview, Comment	Jan 27, 2026 7:00am
workbench-hono-workflow	Ready	Preview, Comment	Jan 27, 2026 7:00am
workbench-nitro-workflow	Ready	Preview, Comment	Jan 27, 2026 7:00am
workbench-nuxt-workflow	Ready	Preview, Comment	Jan 27, 2026 7:00am
workbench-sveltekit-workflow	Ready	Preview, Comment	Jan 27, 2026 7:00am
workbench-vite-workflow	Ready	Preview, Comment	Jan 27, 2026 7:00am
workflow-docs	Ready	Preview, Comment	Jan 27, 2026 7:00am
workflow-nest	Error		Jan 27, 2026 7:00am

[TooTallNate]

• Enable custom class serialization transformations for "client" mode #860 👈 (View in Graphite)
• main

This stack of pull requests is managed by Graphite. Learn more about stacking.

[Copilot]

Pull request overview

This PR enables custom class serialization transformations for "client" mode in the SWC plugin. Previously, class serialization was only handled in workflow and step modes. This change ensures that classes with custom serialization methods can be properly serialized when passed from client code to workflow functions via start(workflow) calls.

Changes:

• Added import generation for registerSerializationClass in client mode when classes need serialization
• Added registration call generation for classes in client mode (both Module and Script cases)
• Updated test fixtures to reflect the new client mode behavior with serialization imports and registration calls

Reviewed changes

Copilot reviewed 7 out of 7 changed files in this pull request and generated 3 comments.

Show a summary per file

File	Description
packages/swc-plugin-workflow/transform/src/lib.rs	Added logic to generate serialization imports and registration calls for client mode in both Module and Script cases
packages/swc-plugin-workflow/transform/tests/fixture/static-method-step/output-client.js	Added expected import and registration call for MyService class
packages/swc-plugin-workflow/transform/tests/fixture/custom-serialization/output-client.js	Added expected import and registration call for Point class
packages/swc-plugin-workflow/transform/tests/fixture/custom-serialization-local-const/output-client.js	Added expected import and registration calls for Circle, Rectangle, and Triangle classes
packages/swc-plugin-workflow/transform/tests/fixture/custom-serialization-imported/output-client.js	Added expected import and registration calls for Color and Vector classes
packages/swc-plugin-workflow/transform/tests/errors/instance-methods/output-client.js	Added expected import and registration call for TestClass
.changeset/modern-clubs-own.md	Added changeset documenting this patch change

---

💡 Add Copilot custom instructions for smarter, more guided reviews. Learn how to get started.

[ijjk]

Seems good but the deduplication callout from copilot does seem good as well

[github-actions]

📊 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	🥇 Next.js (Turbopack)	0.041s (-16.4% 🟢)	1.019s (~)	0.978s	10	1.00x
💻 Local	Express	0.043s (-1.6%)	1.008s (-1.3%)	0.965s	10	1.04x
💻 Local	Nitro	0.043s (-11.1% 🟢)	1.007s (~)	0.964s	10	1.06x
🐘 Postgres	Express	0.127s (-48.6% 🟢)	1.015s (~)	0.888s	10	3.10x
🐘 Postgres	Nitro	0.162s (-60.9% 🟢)	1.026s (+1.2%)	0.864s	10	3.96x
🐘 Postgres	Next.js (Turbopack)	0.242s (+100.4% 🔺)	1.021s (~)	0.778s	10	5.93x

▲ Production (Vercel)

World	Framework	Workflow Time	Wall Time	Overhead	Samples	vs Fastest
▲ Vercel	🥇 Nitro	0.596s (-11.7% 🟢)	1.698s (+12.3% 🔺)	1.101s	10	1.00x
▲ Vercel	Express	0.629s (-18.0% 🟢)	1.601s (-5.4% 🟢)	0.972s	10	1.05x
▲ Vercel	Next.js (Turbopack)	0.695s (-17.4% 🟢)	1.553s (-9.9% 🟢)	0.858s	10	1.17x

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

workflow with 1 step

💻 Local Development

World	Framework	Workflow Time	Wall Time	Overhead	Samples	vs Fastest
💻 Local	🥇 Next.js (Turbopack)	1.103s (~)	2.012s (~)	0.909s	10	1.00x
💻 Local	Express	1.116s (~)	2.008s (~)	0.892s	10	1.01x
💻 Local	Nitro	1.118s (~)	2.007s (~)	0.889s	10	1.01x
🐘 Postgres	Next.js (Turbopack)	2.254s (+17.5% 🔺)	3.019s (+49.8% 🔺)	0.765s	10	2.04x
🐘 Postgres	Express	2.472s (+17.8% 🔺)	3.013s (~)	0.541s	10	2.24x
🐘 Postgres	Nitro	2.473s (+9.2% 🔺)	3.014s (~)	0.542s	10	2.24x

▲ Production (Vercel)

World	Framework	Workflow Time	Wall Time	Overhead	Samples	vs Fastest
▲ Vercel	🥇 Express	2.730s (-1.8%)	3.744s (+3.0%)	1.013s	10	1.00x
▲ Vercel	Nitro	2.874s (~)	3.779s (+4.6%)	0.905s	10	1.05x
▲ Vercel	Next.js (Turbopack)	2.952s (+1.5%)	3.663s (-0.7%)	0.711s	10	1.08x

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

workflow with 10 sequential steps

💻 Local Development

World	Framework	Workflow Time	Wall Time	Overhead	Samples	vs Fastest
💻 Local	🥇 Next.js (Turbopack)	10.716s (~)	11.018s (~)	0.302s	5	1.00x
💻 Local	Nitro	10.841s (~)	11.014s (~)	0.173s	5	1.01x
💻 Local	Express	10.852s (~)	11.013s (~)	0.161s	5	1.01x
🐘 Postgres	Nitro	20.292s (+0.6%)	21.041s (~)	0.750s	5	1.89x
🐘 Postgres	Express	20.310s (+30.5% 🔺)	21.037s (+31.2% 🔺)	0.726s	5	1.90x
🐘 Postgres	Next.js (Turbopack)	20.354s (+40.4% 🔺)	21.043s (+39.9% 🔺)	0.689s	5	1.90x

▲ Production (Vercel)

World	Framework	Workflow Time	Wall Time	Overhead	Samples	vs Fastest
▲ Vercel	🥇 Nitro	22.236s (-6.6% 🟢)	23.066s (-5.8% 🟢)	0.830s	5	1.00x
▲ Vercel	Express	22.515s (-6.9% 🟢)	23.414s (-6.1% 🟢)	0.898s	5	1.01x
▲ Vercel	Next.js (Turbopack)	22.838s (~)	23.452s (-1.4%)	0.614s	5	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
💻 Local	🥇 Next.js (Turbopack)	1.389s (~)	2.012s (~)	0.622s	15	1.00x
💻 Local	Nitro	1.413s (~)	2.007s (~)	0.594s	15	1.02x
💻 Local	Express	1.414s (-0.8%)	2.007s (~)	0.593s	15	1.02x
🐘 Postgres	Next.js (Turbopack)	2.200s (+3.3%)	2.853s (+5.3% 🔺)	0.653s	11	1.58x
🐘 Postgres	Nitro	2.305s (-4.9%)	2.678s (-11.0% 🟢)	0.373s	12	1.66x
🐘 Postgres	Express	2.515s (+21.3% 🔺)	3.014s (+16.0% 🔺)	0.499s	10	1.81x

▲ Production (Vercel)

World	Framework	Workflow Time	Wall Time	Overhead	Samples	vs Fastest
▲ Vercel	🥇 Next.js (Turbopack)	3.000s (-3.5%)	3.773s (-5.5% 🟢)	0.773s	8	1.00x
▲ Vercel	Nitro	3.406s (+7.1% 🔺)	4.360s (+11.9% 🔺)	0.954s	7	1.14x
▲ Vercel	Express	3.551s (+21.7% 🔺)	4.414s (+16.5% 🔺)	0.863s	7	1.18x

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

Promise.all with 25 concurrent steps

💻 Local Development

World	Framework	Workflow Time	Wall Time	Overhead	Samples	vs Fastest
💻 Local	🥇 Next.js (Turbopack)	2.472s (~)	3.066s (-4.3%)	0.594s	10	1.00x
💻 Local	Express	2.502s (-2.0%)	3.029s (+0.5%)	0.527s	10	1.01x
💻 Local	Nitro	2.510s (-2.1%)	3.026s (~)	0.515s	10	1.02x
🐘 Postgres	Express	7.934s (-20.5% 🟢)	8.305s (-20.5% 🟢)	0.371s	4	3.21x
🐘 Postgres	Nitro	8.839s (+18.5% 🔺)	9.274s (+14.9% 🔺)	0.435s	4	3.58x
🐘 Postgres	Next.js (Turbopack)	11.559s (-0.8%)	12.037s (-0.7%)	0.478s	3	4.68x

▲ Production (Vercel)

World	Framework	Workflow Time	Wall Time	Overhead	Samples	vs Fastest
▲ Vercel	🥇 Next.js (Turbopack)	3.235s (-6.5% 🟢)	4.052s (-0.7%)	0.817s	8	1.00x
▲ Vercel	Express	3.374s (+2.4%)	4.168s (+2.8%)	0.795s	8	1.04x
▲ Vercel	Nitro	3.535s (+15.7% 🔺)	4.228s (+10.6% 🔺)	0.694s	8	1.09x

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

Promise.race with 10 concurrent steps

💻 Local Development

World	Framework	Workflow Time	Wall Time	Overhead	Samples	vs Fastest
💻 Local	🥇 Nitro	1.409s (-2.7%)	2.007s (~)	0.598s	15	1.00x
💻 Local	Next.js (Turbopack)	1.427s (+1.0%)	2.013s (~)	0.586s	15	1.01x
💻 Local	Express	1.434s (~)	2.006s (~)	0.572s	15	1.02x
🐘 Postgres	Nitro	1.967s (-8.0% 🟢)	2.477s (-4.7%)	0.511s	13	1.40x
🐘 Postgres	Express	2.061s (+14.5% 🔺)	2.528s (+13.3% 🔺)	0.467s	12	1.46x
🐘 Postgres	Next.js (Turbopack)	2.299s (-2.5%)	2.746s (-9.2% 🟢)	0.447s	11	1.63x

▲ Production (Vercel)

World	Framework	Workflow Time	Wall Time	Overhead	Samples	vs Fastest
▲ Vercel	🥇 Nitro	2.838s (+1.0%)	3.792s (+3.6%)	0.953s	8	1.00x
▲ Vercel	Express	2.853s (+0.9%)	3.886s (+5.3% 🔺)	1.033s	8	1.01x
▲ Vercel	Next.js (Turbopack)	3.017s (+5.7% 🔺)	4.024s (+9.6% 🔺)	1.007s	8	1.06x

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

Promise.race with 25 concurrent steps

💻 Local Development

World	Framework	Workflow Time	Wall Time	Overhead	Samples	vs Fastest
💻 Local	🥇 Next.js (Turbopack)	2.536s (~)	3.102s (+1.6%)	0.566s	10	1.00x
💻 Local	Express	2.568s (-2.8%)	3.022s (~)	0.454s	10	1.01x
💻 Local	Nitro	2.596s (-0.5%)	3.022s (~)	0.427s	10	1.02x
🐘 Postgres	Nitro	11.622s (-3.4%)	12.050s (-2.8%)	0.428s	3	4.58x
🐘 Postgres	Express	12.974s (+6.7% 🔺)	13.022s (+2.5%)	0.048s	3	5.12x
🐘 Postgres	Next.js (Turbopack)	13.121s (-5.6% 🟢)	13.705s (-4.6%)	0.584s	3	5.17x

▲ Production (Vercel)

World	Framework	Workflow Time	Wall Time	Overhead	Samples	vs Fastest
▲ Vercel	🥇 Nitro	3.089s (-21.8% 🟢)	3.948s (-18.8% 🟢)	0.859s	8	1.00x
▲ Vercel	Next.js (Turbopack)	3.263s (+4.6%)	4.032s (+6.9% 🔺)	0.769s	8	1.06x
▲ Vercel	Express	3.657s (+2.4%)	4.312s (-0.8%)	0.655s	7	1.18x

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

Stream Benchmarks(includes TTFB metrics)

workflow with stream

💻 Local Development

World	Framework	Workflow Time	TTFB	Slurp	Wall Time	Overhead	Samples	vs Fastest
💻 Local	🥇 Next.js (Turbopack)	0.144s (+1.6%)	1.004s (~)	0.016s (-12.2% 🟢)	1.027s (~)	0.884s	10	1.00x
💻 Local	Express	0.184s (-0.7%)	0.992s (~)	0.018s (+19.9% 🔺)	1.024s (~)	0.841s	10	1.28x
💻 Local	Nitro	0.188s (-0.6%)	0.993s (~)	0.015s (-2.6%)	1.022s (~)	0.834s	10	1.31x
🐘 Postgres	Next.js (Turbopack)	1.304s (+107.0% 🔺)	2.040s (+109.8% 🔺)	0.000s (NaN%)	2.120s (+108.6% 🔺)	0.816s	10	9.07x
🐘 Postgres	Nitro	1.451s (-41.4% 🟢)	2.266s (-11.6% 🟢)	0.000s (-100.0% 🟢)	2.314s (-23.2% 🟢)	0.863s	10	10.10x
🐘 Postgres	Express	2.104s (+65.2% 🔺)	2.936s (+66.6% 🔺)	0.000s (NaN%)	3.016s (+49.7% 🔺)	0.911s	10	14.64x

▲ Production (Vercel)

World	Framework	Workflow Time	TTFB	Slurp	Wall Time	Overhead	Samples	vs Fastest
▲ Vercel	🥇 Next.js (Turbopack)	2.932s (-4.8%)	3.245s (+2.3%)	0.537s (-33.6% 🟢)	4.267s (-5.6% 🟢)	1.335s	10	1.00x
▲ Vercel	Nitro	3.058s (-0.7%)	3.228s (+1.8%)	0.672s (-35.1% 🟢)	4.459s (-7.0% 🟢)	1.401s	10	1.04x
▲ Vercel	Express	3.100s (+2.6%)	3.330s (+2.9%)	0.518s (-13.5% 🟢)	4.388s (+1.7%)	1.288s	10	1.06x

🔍 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)	7/8
🐘 Postgres	Next.js (Turbopack)	3/8
▲ Vercel	Nitro	4/8

Fastest World by Framework

Winner determined by most benchmark wins

Framework	🥇 Fastest World	Wins
Express	💻 Local	8/8
Next.js (Turbopack)	💻 Local	8/8
Nitro	💻 Local	8/8

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

[vercel]

🔧 Build Fix:

The OpenAI class is not constructable in the imported module. This is a type error where the code is trying to instantiate the OpenAI class, but the module export doesn't provide a constructor signature.

[TooTallNate]

Enable class serialization in client mode to support passing class instances to workflow functions.

What changed?

• Added support for class serialization transformations in "client" mode
• The plugin now generates necessary imports and registration calls for classes that need serialization in client mode
• When classes are detected that need serialization, the plugin:
  • Imports registerSerializationClass from "workflow/internal/class-serialization"
  • Adds registration calls for each class with a unique class ID
• Updated test outputs to reflect these changes

How to test?

1. Create a class with serialization methods (using WORKFLOW_SERIALIZE and WORKFLOW_DESERIALIZE symbols)
2. Use the class in a client-side context where it's passed to a workflow function
3. Verify that the class is properly serialized and deserialized when passed between client and workflow

Why make this change?

Previously, class serialization was only enabled in workflow mode, which meant that classes couldn't be properly serialized when passed from client code to workflow functions. This change ensures that classes with custom serialization methods work correctly when used as arguments to start(workflow) calls from client code.

[changeset-bot]

🦋 Changeset detected

Latest commit: 1a72c70

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

This PR includes changesets to release 15 packages

Name	Type
@workflow/swc-plugin	Patch
@workflow/astro	Patch
@workflow/builders	Patch
@workflow/cli	Patch
@workflow/nest	Patch
@workflow/next	Patch
@workflow/nitro	Patch
@workflow/rollup	Patch
@workflow/sveltekit	Patch
workflow	Patch
@workflow/world-testing	Patch
@workflow/example-nest	Patch
@workflow/docs-typecheck	Patch
@workflow/nuxt	Patch
@workflow/ai	Patch

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

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

[github-actions]

🧪 E2E Test Results

❌ Some tests failed

Summary

	Passed	Failed	Skipped	Total
✅ ▲ Vercel Production	457	0	38	495
❌ 💻 Local Development	416	2	32	450
✅ 📦 Local Production	418	0	32	450
✅ 🐘 Local Postgres	418	0	32	450
✅ 🪟 Windows	45	0	0	45
❌ 🌍 Community Worlds	31	161	0	192
✅ 📋 Other	123	0	12	135
Total	1908	163	146	2217

❌ Failed Tests

💻 Local Development (2 failed)

astro-stable (2 failed):

• 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

🌍 Community Worlds (161 failed)

mongodb (40 failed):

• addTenWorkflow
• addTenWorkflow
• should work with react rendering in step
• promiseAllWorkflow
• promiseRaceWorkflow
• promiseAnyWorkflow
• readableStreamWorkflow
• hookWorkflow
• webhookWorkflow
• sleepingWorkflow
• nullByteWorkflow
• workflowAndStepMetadataWorkflow
• outputStreamWorkflow
• outputStreamInsideStepWorkflow - getWritable() called inside step functions
• 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
• 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
• pages router addTenWorkflow via pages router
• pages router promiseAllWorkflow via pages router
• pages router sleepingWorkflow via pages router

redis (40 failed):

• addTenWorkflow
• addTenWorkflow
• should work with react rendering in step
• promiseAllWorkflow
• promiseRaceWorkflow
• promiseAnyWorkflow
• readableStreamWorkflow
• hookWorkflow
• webhookWorkflow
• sleepingWorkflow
• nullByteWorkflow
• workflowAndStepMetadataWorkflow
• outputStreamWorkflow
• outputStreamInsideStepWorkflow - getWritable() called inside step functions
• 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
• 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
• pages router addTenWorkflow via pages router
• pages router promiseAllWorkflow via pages router
• pages router sleepingWorkflow via pages router

starter (41 failed):

• addTenWorkflow
• addTenWorkflow
• should work with react rendering in step
• promiseAllWorkflow
• promiseRaceWorkflow
• promiseAnyWorkflow
• readableStreamWorkflow
• hookWorkflow
• webhookWorkflow
• sleepingWorkflow
• nullByteWorkflow
• workflowAndStepMetadataWorkflow
• outputStreamWorkflow
• outputStreamInsideStepWorkflow - getWritable() called inside step functions
• 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 (CLI) - workflow health command reports healthy endpoints
• 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
• pages router addTenWorkflow via pages router
• pages router promiseAllWorkflow via pages router
• pages router sleepingWorkflow via pages router

turso (40 failed):

• addTenWorkflow
• addTenWorkflow
• should work with react rendering in step
• promiseAllWorkflow
• promiseRaceWorkflow
• promiseAnyWorkflow
• readableStreamWorkflow
• hookWorkflow
• webhookWorkflow
• sleepingWorkflow
• nullByteWorkflow
• workflowAndStepMetadataWorkflow
• outputStreamWorkflow
• outputStreamInsideStepWorkflow - getWritable() called inside step functions
• 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
• 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
• 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	41	0	4
✅ example	41	0	4
✅ express	41	0	4
✅ fastify	41	0	4
✅ hono	41	0	4
✅ nextjs-turbopack	44	0	1
✅ nextjs-webpack	44	0	1
✅ nitro	41	0	4
✅ nuxt	41	0	4
✅ sveltekit	41	0	4
✅ vite	41	0	4

❌ 💻 Local Development

App	Passed	Failed	Skipped
❌ astro-stable	39	2	4
✅ express-stable	41	0	4
✅ fastify-stable	41	0	4
✅ hono-stable	41	0	4
✅ nextjs-turbopack-stable	45	0	0
✅ nextjs-webpack-stable	45	0	0
✅ nitro-stable	41	0	4
✅ nuxt-stable	41	0	4
✅ sveltekit-stable	41	0	4
✅ vite-stable	41	0	4

✅ 📦 Local Production

App	Passed	Failed	Skipped
✅ astro-stable	41	0	4
✅ express-stable	41	0	4
✅ fastify-stable	41	0	4
✅ hono-stable	41	0	4
✅ nextjs-turbopack-stable	45	0	0
✅ nextjs-webpack-stable	45	0	0
✅ nitro-stable	41	0	4
✅ nuxt-stable	41	0	4
✅ sveltekit-stable	41	0	4
✅ vite-stable	41	0	4

✅ 🐘 Local Postgres

App	Passed	Failed	Skipped
✅ astro-stable	41	0	4
✅ express-stable	41	0	4
✅ fastify-stable	41	0	4
✅ hono-stable	41	0	4
✅ nextjs-turbopack-stable	45	0	0
✅ nextjs-webpack-stable	45	0	0
✅ nitro-stable	41	0	4
✅ nuxt-stable	41	0	4
✅ sveltekit-stable	41	0	4
✅ vite-stable	41	0	4

✅ 🪟 Windows

App	Passed	Failed	Skipped
✅ nextjs-turbopack	45	0	0

❌ 🌍 Community Worlds

App	Passed	Failed	Skipped
✅ mongodb-dev	3	0	0
❌ mongodb	5	40	0
✅ redis-dev	3	0	0
❌ redis	5	40	0
✅ starter-dev	3	0	0
❌ starter	4	41	0
✅ turso-dev	3	0	0
❌ turso	5	40	0

✅ 📋 Other

App	Passed	Failed	Skipped
✅ e2e-local-dev-nest-stable	41	0	4
✅ e2e-local-postgres-nest-stable	41	0	4
✅ e2e-local-prod-nest-stable	41	0	4

---

📋 View full workflow run

---

❌ Some E2E test jobs failed:

• Vercel Prod: success
• Local Dev: failure
• Local Prod: success
• Local Postgres: success
• Windows: success

Check the workflow run for details.

[vercel]

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

Project	Deployment	Review	Updated (UTC)
example-nextjs-workflow-turbopack	Ready	Preview, Comment	Jan 27, 2026 7:00am
example-nextjs-workflow-webpack	Ready	Preview, Comment	Jan 27, 2026 7:00am
example-workflow	Ready	Preview, Comment	Jan 27, 2026 7:00am
workbench-astro-workflow	Ready	Preview, Comment	Jan 27, 2026 7:00am
workbench-express-workflow	Ready	Preview, Comment	Jan 27, 2026 7:00am
workbench-fastify-workflow	Ready	Preview, Comment	Jan 27, 2026 7:00am
workbench-hono-workflow	Ready	Preview, Comment	Jan 27, 2026 7:00am
workbench-nitro-workflow	Ready	Preview, Comment	Jan 27, 2026 7:00am
workbench-nuxt-workflow	Ready	Preview, Comment	Jan 27, 2026 7:00am
workbench-sveltekit-workflow	Ready	Preview, Comment	Jan 27, 2026 7:00am
workbench-vite-workflow	Ready	Preview, Comment	Jan 27, 2026 7:00am
workflow-docs	Ready	Preview, Comment	Jan 27, 2026 7:00am
workflow-nest	Error		Jan 27, 2026 7:00am

[TooTallNate]

• Enable custom class serialization transformations for "client" mode #860 👈 (View in Graphite)
• main

This stack of pull requests is managed by Graphite. Learn more about stacking.

[Copilot]

Pull request overview

This PR enables custom class serialization transformations for "client" mode in the SWC plugin. Previously, class serialization was only handled in workflow and step modes. This change ensures that classes with custom serialization methods can be properly serialized when passed from client code to workflow functions via start(workflow) calls.

Changes:

• Added import generation for registerSerializationClass in client mode when classes need serialization
• Added registration call generation for classes in client mode (both Module and Script cases)
• Updated test fixtures to reflect the new client mode behavior with serialization imports and registration calls

Reviewed changes

Copilot reviewed 7 out of 7 changed files in this pull request and generated 3 comments.

Show a summary per file

File	Description
packages/swc-plugin-workflow/transform/src/lib.rs	Added logic to generate serialization imports and registration calls for client mode in both Module and Script cases
packages/swc-plugin-workflow/transform/tests/fixture/static-method-step/output-client.js	Added expected import and registration call for MyService class
packages/swc-plugin-workflow/transform/tests/fixture/custom-serialization/output-client.js	Added expected import and registration call for Point class
packages/swc-plugin-workflow/transform/tests/fixture/custom-serialization-local-const/output-client.js	Added expected import and registration calls for Circle, Rectangle, and Triangle classes
packages/swc-plugin-workflow/transform/tests/fixture/custom-serialization-imported/output-client.js	Added expected import and registration calls for Color and Vector classes
packages/swc-plugin-workflow/transform/tests/errors/instance-methods/output-client.js	Added expected import and registration call for TestClass
.changeset/modern-clubs-own.md	Added changeset documenting this patch change

---

💡 Add Copilot custom instructions for smarter, more guided reviews. Learn how to get started.

[ijjk]

Seems good but the deduplication callout from copilot does seem good as well

[github-actions]

📊 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	🥇 Next.js (Turbopack)	0.041s (-16.4% 🟢)	1.019s (~)	0.978s	10	1.00x
💻 Local	Express	0.043s (-1.6%)	1.008s (-1.3%)	0.965s	10	1.04x
💻 Local	Nitro	0.043s (-11.1% 🟢)	1.007s (~)	0.964s	10	1.06x
🐘 Postgres	Express	0.127s (-48.6% 🟢)	1.015s (~)	0.888s	10	3.10x
🐘 Postgres	Nitro	0.162s (-60.9% 🟢)	1.026s (+1.2%)	0.864s	10	3.96x
🐘 Postgres	Next.js (Turbopack)	0.242s (+100.4% 🔺)	1.021s (~)	0.778s	10	5.93x

▲ Production (Vercel)

World	Framework	Workflow Time	Wall Time	Overhead	Samples	vs Fastest
▲ Vercel	🥇 Nitro	0.596s (-11.7% 🟢)	1.698s (+12.3% 🔺)	1.101s	10	1.00x
▲ Vercel	Express	0.629s (-18.0% 🟢)	1.601s (-5.4% 🟢)	0.972s	10	1.05x
▲ Vercel	Next.js (Turbopack)	0.695s (-17.4% 🟢)	1.553s (-9.9% 🟢)	0.858s	10	1.17x

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

workflow with 1 step

💻 Local Development

World	Framework	Workflow Time	Wall Time	Overhead	Samples	vs Fastest
💻 Local	🥇 Next.js (Turbopack)	1.103s (~)	2.012s (~)	0.909s	10	1.00x
💻 Local	Express	1.116s (~)	2.008s (~)	0.892s	10	1.01x
💻 Local	Nitro	1.118s (~)	2.007s (~)	0.889s	10	1.01x
🐘 Postgres	Next.js (Turbopack)	2.254s (+17.5% 🔺)	3.019s (+49.8% 🔺)	0.765s	10	2.04x
🐘 Postgres	Express	2.472s (+17.8% 🔺)	3.013s (~)	0.541s	10	2.24x
🐘 Postgres	Nitro	2.473s (+9.2% 🔺)	3.014s (~)	0.542s	10	2.24x

▲ Production (Vercel)

World	Framework	Workflow Time	Wall Time	Overhead	Samples	vs Fastest
▲ Vercel	🥇 Express	2.730s (-1.8%)	3.744s (+3.0%)	1.013s	10	1.00x
▲ Vercel	Nitro	2.874s (~)	3.779s (+4.6%)	0.905s	10	1.05x
▲ Vercel	Next.js (Turbopack)	2.952s (+1.5%)	3.663s (-0.7%)	0.711s	10	1.08x

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

workflow with 10 sequential steps

💻 Local Development

World	Framework	Workflow Time	Wall Time	Overhead	Samples	vs Fastest
💻 Local	🥇 Next.js (Turbopack)	10.716s (~)	11.018s (~)	0.302s	5	1.00x
💻 Local	Nitro	10.841s (~)	11.014s (~)	0.173s	5	1.01x
💻 Local	Express	10.852s (~)	11.013s (~)	0.161s	5	1.01x
🐘 Postgres	Nitro	20.292s (+0.6%)	21.041s (~)	0.750s	5	1.89x
🐘 Postgres	Express	20.310s (+30.5% 🔺)	21.037s (+31.2% 🔺)	0.726s	5	1.90x
🐘 Postgres	Next.js (Turbopack)	20.354s (+40.4% 🔺)	21.043s (+39.9% 🔺)	0.689s	5	1.90x

▲ Production (Vercel)

World	Framework	Workflow Time	Wall Time	Overhead	Samples	vs Fastest
▲ Vercel	🥇 Nitro	22.236s (-6.6% 🟢)	23.066s (-5.8% 🟢)	0.830s	5	1.00x
▲ Vercel	Express	22.515s (-6.9% 🟢)	23.414s (-6.1% 🟢)	0.898s	5	1.01x
▲ Vercel	Next.js (Turbopack)	22.838s (~)	23.452s (-1.4%)	0.614s	5	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
💻 Local	🥇 Next.js (Turbopack)	1.389s (~)	2.012s (~)	0.622s	15	1.00x
💻 Local	Nitro	1.413s (~)	2.007s (~)	0.594s	15	1.02x
💻 Local	Express	1.414s (-0.8%)	2.007s (~)	0.593s	15	1.02x
🐘 Postgres	Next.js (Turbopack)	2.200s (+3.3%)	2.853s (+5.3% 🔺)	0.653s	11	1.58x
🐘 Postgres	Nitro	2.305s (-4.9%)	2.678s (-11.0% 🟢)	0.373s	12	1.66x
🐘 Postgres	Express	2.515s (+21.3% 🔺)	3.014s (+16.0% 🔺)	0.499s	10	1.81x

▲ Production (Vercel)

World	Framework	Workflow Time	Wall Time	Overhead	Samples	vs Fastest
▲ Vercel	🥇 Next.js (Turbopack)	3.000s (-3.5%)	3.773s (-5.5% 🟢)	0.773s	8	1.00x
▲ Vercel	Nitro	3.406s (+7.1% 🔺)	4.360s (+11.9% 🔺)	0.954s	7	1.14x
▲ Vercel	Express	3.551s (+21.7% 🔺)	4.414s (+16.5% 🔺)	0.863s	7	1.18x

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

Promise.all with 25 concurrent steps

💻 Local Development

World	Framework	Workflow Time	Wall Time	Overhead	Samples	vs Fastest
💻 Local	🥇 Next.js (Turbopack)	2.472s (~)	3.066s (-4.3%)	0.594s	10	1.00x
💻 Local	Express	2.502s (-2.0%)	3.029s (+0.5%)	0.527s	10	1.01x
💻 Local	Nitro	2.510s (-2.1%)	3.026s (~)	0.515s	10	1.02x
🐘 Postgres	Express	7.934s (-20.5% 🟢)	8.305s (-20.5% 🟢)	0.371s	4	3.21x
🐘 Postgres	Nitro	8.839s (+18.5% 🔺)	9.274s (+14.9% 🔺)	0.435s	4	3.58x
🐘 Postgres	Next.js (Turbopack)	11.559s (-0.8%)	12.037s (-0.7%)	0.478s	3	4.68x

▲ Production (Vercel)

World	Framework	Workflow Time	Wall Time	Overhead	Samples	vs Fastest
▲ Vercel	🥇 Next.js (Turbopack)	3.235s (-6.5% 🟢)	4.052s (-0.7%)	0.817s	8	1.00x
▲ Vercel	Express	3.374s (+2.4%)	4.168s (+2.8%)	0.795s	8	1.04x
▲ Vercel	Nitro	3.535s (+15.7% 🔺)	4.228s (+10.6% 🔺)	0.694s	8	1.09x

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

Promise.race with 10 concurrent steps

💻 Local Development

World	Framework	Workflow Time	Wall Time	Overhead	Samples	vs Fastest
💻 Local	🥇 Nitro	1.409s (-2.7%)	2.007s (~)	0.598s	15	1.00x
💻 Local	Next.js (Turbopack)	1.427s (+1.0%)	2.013s (~)	0.586s	15	1.01x
💻 Local	Express	1.434s (~)	2.006s (~)	0.572s	15	1.02x
🐘 Postgres	Nitro	1.967s (-8.0% 🟢)	2.477s (-4.7%)	0.511s	13	1.40x
🐘 Postgres	Express	2.061s (+14.5% 🔺)	2.528s (+13.3% 🔺)	0.467s	12	1.46x
🐘 Postgres	Next.js (Turbopack)	2.299s (-2.5%)	2.746s (-9.2% 🟢)	0.447s	11	1.63x

▲ Production (Vercel)

World	Framework	Workflow Time	Wall Time	Overhead	Samples	vs Fastest
▲ Vercel	🥇 Nitro	2.838s (+1.0%)	3.792s (+3.6%)	0.953s	8	1.00x
▲ Vercel	Express	2.853s (+0.9%)	3.886s (+5.3% 🔺)	1.033s	8	1.01x
▲ Vercel	Next.js (Turbopack)	3.017s (+5.7% 🔺)	4.024s (+9.6% 🔺)	1.007s	8	1.06x

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

Promise.race with 25 concurrent steps

💻 Local Development

World	Framework	Workflow Time	Wall Time	Overhead	Samples	vs Fastest
💻 Local	🥇 Next.js (Turbopack)	2.536s (~)	3.102s (+1.6%)	0.566s	10	1.00x
💻 Local	Express	2.568s (-2.8%)	3.022s (~)	0.454s	10	1.01x
💻 Local	Nitro	2.596s (-0.5%)	3.022s (~)	0.427s	10	1.02x
🐘 Postgres	Nitro	11.622s (-3.4%)	12.050s (-2.8%)	0.428s	3	4.58x
🐘 Postgres	Express	12.974s (+6.7% 🔺)	13.022s (+2.5%)	0.048s	3	5.12x
🐘 Postgres	Next.js (Turbopack)	13.121s (-5.6% 🟢)	13.705s (-4.6%)	0.584s	3	5.17x

▲ Production (Vercel)

World	Framework	Workflow Time	Wall Time	Overhead	Samples	vs Fastest
▲ Vercel	🥇 Nitro	3.089s (-21.8% 🟢)	3.948s (-18.8% 🟢)	0.859s	8	1.00x
▲ Vercel	Next.js (Turbopack)	3.263s (+4.6%)	4.032s (+6.9% 🔺)	0.769s	8	1.06x
▲ Vercel	Express	3.657s (+2.4%)	4.312s (-0.8%)	0.655s	7	1.18x

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

Stream Benchmarks(includes TTFB metrics)

workflow with stream

💻 Local Development

World	Framework	Workflow Time	TTFB	Slurp	Wall Time	Overhead	Samples	vs Fastest
💻 Local	🥇 Next.js (Turbopack)	0.144s (+1.6%)	1.004s (~)	0.016s (-12.2% 🟢)	1.027s (~)	0.884s	10	1.00x
💻 Local	Express	0.184s (-0.7%)	0.992s (~)	0.018s (+19.9% 🔺)	1.024s (~)	0.841s	10	1.28x
💻 Local	Nitro	0.188s (-0.6%)	0.993s (~)	0.015s (-2.6%)	1.022s (~)	0.834s	10	1.31x
🐘 Postgres	Next.js (Turbopack)	1.304s (+107.0% 🔺)	2.040s (+109.8% 🔺)	0.000s (NaN%)	2.120s (+108.6% 🔺)	0.816s	10	9.07x
🐘 Postgres	Nitro	1.451s (-41.4% 🟢)	2.266s (-11.6% 🟢)	0.000s (-100.0% 🟢)	2.314s (-23.2% 🟢)	0.863s	10	10.10x
🐘 Postgres	Express	2.104s (+65.2% 🔺)	2.936s (+66.6% 🔺)	0.000s (NaN%)	3.016s (+49.7% 🔺)	0.911s	10	14.64x

▲ Production (Vercel)

World	Framework	Workflow Time	TTFB	Slurp	Wall Time	Overhead	Samples	vs Fastest
▲ Vercel	🥇 Next.js (Turbopack)	2.932s (-4.8%)	3.245s (+2.3%)	0.537s (-33.6% 🟢)	4.267s (-5.6% 🟢)	1.335s	10	1.00x
▲ Vercel	Nitro	3.058s (-0.7%)	3.228s (+1.8%)	0.672s (-35.1% 🟢)	4.459s (-7.0% 🟢)	1.401s	10	1.04x
▲ Vercel	Express	3.100s (+2.6%)	3.330s (+2.9%)	0.518s (-13.5% 🟢)	4.388s (+1.7%)	1.288s	10	1.06x

🔍 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)	7/8
🐘 Postgres	Next.js (Turbopack)	3/8
▲ Vercel	Nitro	4/8

Fastest World by Framework

Winner determined by most benchmark wins

Framework	🥇 Fastest World	Wins
Express	💻 Local	8/8
Next.js (Turbopack)	💻 Local	8/8
Nitro	💻 Local	8/8

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

[vercel]

🔧 Build Fix:

The OpenAI class is not constructable in the imported module. This is a type error where the code is trying to instantiate the OpenAI class, but the module export doesn't provide a constructor signature.

[TooTallNate]

Enable class serialization in client mode to support passing class instances to workflow functions.

What changed?

• Added support for class serialization transformations in "client" mode
• The plugin now generates necessary imports and registration calls for classes that need serialization in client mode
• When classes are detected that need serialization, the plugin:
  • Imports registerSerializationClass from "workflow/internal/class-serialization"
  • Adds registration calls for each class with a unique class ID
• Updated test outputs to reflect these changes

How to test?

1. Create a class with serialization methods (using WORKFLOW_SERIALIZE and WORKFLOW_DESERIALIZE symbols)
2. Use the class in a client-side context where it's passed to a workflow function
3. Verify that the class is properly serialized and deserialized when passed between client and workflow

Why make this change?

Previously, class serialization was only enabled in workflow mode, which meant that classes couldn't be properly serialized when passed from client code to workflow functions. This change ensures that classes with custom serialization methods work correctly when used as arguments to start(workflow) calls from client code.

[changeset-bot]

🦋 Changeset detected

Latest commit: 1a72c70

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

This PR includes changesets to release 15 packages

Name	Type
@workflow/swc-plugin	Patch
@workflow/astro	Patch
@workflow/builders	Patch
@workflow/cli	Patch
@workflow/nest	Patch
@workflow/next	Patch
@workflow/nitro	Patch
@workflow/rollup	Patch
@workflow/sveltekit	Patch
workflow	Patch
@workflow/world-testing	Patch
@workflow/example-nest	Patch
@workflow/docs-typecheck	Patch
@workflow/nuxt	Patch
@workflow/ai	Patch

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

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

[github-actions]

🧪 E2E Test Results

❌ Some tests failed

Summary

	Passed	Failed	Skipped	Total
✅ ▲ Vercel Production	457	0	38	495
❌ 💻 Local Development	416	2	32	450
✅ 📦 Local Production	418	0	32	450
✅ 🐘 Local Postgres	418	0	32	450
✅ 🪟 Windows	45	0	0	45
❌ 🌍 Community Worlds	31	161	0	192
✅ 📋 Other	123	0	12	135
Total	1908	163	146	2217

❌ Failed Tests

💻 Local Development (2 failed)

astro-stable (2 failed):

• 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

🌍 Community Worlds (161 failed)

mongodb (40 failed):

• addTenWorkflow
• addTenWorkflow
• should work with react rendering in step
• promiseAllWorkflow
• promiseRaceWorkflow
• promiseAnyWorkflow
• readableStreamWorkflow
• hookWorkflow
• webhookWorkflow
• sleepingWorkflow
• nullByteWorkflow
• workflowAndStepMetadataWorkflow
• outputStreamWorkflow
• outputStreamInsideStepWorkflow - getWritable() called inside step functions
• 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
• 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
• pages router addTenWorkflow via pages router
• pages router promiseAllWorkflow via pages router
• pages router sleepingWorkflow via pages router

redis (40 failed):

• addTenWorkflow
• addTenWorkflow
• should work with react rendering in step
• promiseAllWorkflow
• promiseRaceWorkflow
• promiseAnyWorkflow
• readableStreamWorkflow
• hookWorkflow
• webhookWorkflow
• sleepingWorkflow
• nullByteWorkflow
• workflowAndStepMetadataWorkflow
• outputStreamWorkflow
• outputStreamInsideStepWorkflow - getWritable() called inside step functions
• 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
• 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
• pages router addTenWorkflow via pages router
• pages router promiseAllWorkflow via pages router
• pages router sleepingWorkflow via pages router

starter (41 failed):

• addTenWorkflow
• addTenWorkflow
• should work with react rendering in step
• promiseAllWorkflow
• promiseRaceWorkflow
• promiseAnyWorkflow
• readableStreamWorkflow
• hookWorkflow
• webhookWorkflow
• sleepingWorkflow
• nullByteWorkflow
• workflowAndStepMetadataWorkflow
• outputStreamWorkflow
• outputStreamInsideStepWorkflow - getWritable() called inside step functions
• 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 (CLI) - workflow health command reports healthy endpoints
• 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
• pages router addTenWorkflow via pages router
• pages router promiseAllWorkflow via pages router
• pages router sleepingWorkflow via pages router

turso (40 failed):

• addTenWorkflow
• addTenWorkflow
• should work with react rendering in step
• promiseAllWorkflow
• promiseRaceWorkflow
• promiseAnyWorkflow
• readableStreamWorkflow
• hookWorkflow
• webhookWorkflow
• sleepingWorkflow
• nullByteWorkflow
• workflowAndStepMetadataWorkflow
• outputStreamWorkflow
• outputStreamInsideStepWorkflow - getWritable() called inside step functions
• 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
• 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
• 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	41	0	4
✅ example	41	0	4
✅ express	41	0	4
✅ fastify	41	0	4
✅ hono	41	0	4
✅ nextjs-turbopack	44	0	1
✅ nextjs-webpack	44	0	1
✅ nitro	41	0	4
✅ nuxt	41	0	4
✅ sveltekit	41	0	4
✅ vite	41	0	4

❌ 💻 Local Development

App	Passed	Failed	Skipped
❌ astro-stable	39	2	4
✅ express-stable	41	0	4
✅ fastify-stable	41	0	4
✅ hono-stable	41	0	4
✅ nextjs-turbopack-stable	45	0	0
✅ nextjs-webpack-stable	45	0	0
✅ nitro-stable	41	0	4
✅ nuxt-stable	41	0	4
✅ sveltekit-stable	41	0	4
✅ vite-stable	41	0	4

✅ 📦 Local Production

App	Passed	Failed	Skipped
✅ astro-stable	41	0	4
✅ express-stable	41	0	4
✅ fastify-stable	41	0	4
✅ hono-stable	41	0	4
✅ nextjs-turbopack-stable	45	0	0
✅ nextjs-webpack-stable	45	0	0
✅ nitro-stable	41	0	4
✅ nuxt-stable	41	0	4
✅ sveltekit-stable	41	0	4
✅ vite-stable	41	0	4

✅ 🐘 Local Postgres

App	Passed	Failed	Skipped
✅ astro-stable	41	0	4
✅ express-stable	41	0	4
✅ fastify-stable	41	0	4
✅ hono-stable	41	0	4
✅ nextjs-turbopack-stable	45	0	0
✅ nextjs-webpack-stable	45	0	0
✅ nitro-stable	41	0	4
✅ nuxt-stable	41	0	4
✅ sveltekit-stable	41	0	4
✅ vite-stable	41	0	4

✅ 🪟 Windows

App	Passed	Failed	Skipped
✅ nextjs-turbopack	45	0	0

❌ 🌍 Community Worlds

App	Passed	Failed	Skipped
✅ mongodb-dev	3	0	0
❌ mongodb	5	40	0
✅ redis-dev	3	0	0
❌ redis	5	40	0
✅ starter-dev	3	0	0
❌ starter	4	41	0
✅ turso-dev	3	0	0
❌ turso	5	40	0

✅ 📋 Other

App	Passed	Failed	Skipped
✅ e2e-local-dev-nest-stable	41	0	4
✅ e2e-local-postgres-nest-stable	41	0	4
✅ e2e-local-prod-nest-stable	41	0	4

---

📋 View full workflow run

---

❌ Some E2E test jobs failed:

• Vercel Prod: success
• Local Dev: failure
• Local Prod: success
• Local Postgres: success
• Windows: success

Check the workflow run for details.

[vercel]

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

Project	Deployment	Review	Updated (UTC)
example-nextjs-workflow-turbopack	Ready	Preview, Comment	Jan 27, 2026 7:00am
example-nextjs-workflow-webpack	Ready	Preview, Comment	Jan 27, 2026 7:00am
example-workflow	Ready	Preview, Comment	Jan 27, 2026 7:00am
workbench-astro-workflow	Ready	Preview, Comment	Jan 27, 2026 7:00am
workbench-express-workflow	Ready	Preview, Comment	Jan 27, 2026 7:00am
workbench-fastify-workflow	Ready	Preview, Comment	Jan 27, 2026 7:00am
workbench-hono-workflow	Ready	Preview, Comment	Jan 27, 2026 7:00am
workbench-nitro-workflow	Ready	Preview, Comment	Jan 27, 2026 7:00am
workbench-nuxt-workflow	Ready	Preview, Comment	Jan 27, 2026 7:00am
workbench-sveltekit-workflow	Ready	Preview, Comment	Jan 27, 2026 7:00am
workbench-vite-workflow	Ready	Preview, Comment	Jan 27, 2026 7:00am
workflow-docs	Ready	Preview, Comment	Jan 27, 2026 7:00am
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[TooTallNate]

• Enable custom class serialization transformations for "client" mode #860 👈 (View in Graphite)
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[Copilot]

Pull request overview

This PR enables custom class serialization transformations for "client" mode in the SWC plugin. Previously, class serialization was only handled in workflow and step modes. This change ensures that classes with custom serialization methods can be properly serialized when passed from client code to workflow functions via start(workflow) calls.

Changes:

• Added import generation for registerSerializationClass in client mode when classes need serialization
• Added registration call generation for classes in client mode (both Module and Script cases)
• Updated test fixtures to reflect the new client mode behavior with serialization imports and registration calls

Reviewed changes

Copilot reviewed 7 out of 7 changed files in this pull request and generated 3 comments.

Show a summary per file

File	Description
packages/swc-plugin-workflow/transform/src/lib.rs	Added logic to generate serialization imports and registration calls for client mode in both Module and Script cases
packages/swc-plugin-workflow/transform/tests/fixture/static-method-step/output-client.js	Added expected import and registration call for MyService class
packages/swc-plugin-workflow/transform/tests/fixture/custom-serialization/output-client.js	Added expected import and registration call for Point class
packages/swc-plugin-workflow/transform/tests/fixture/custom-serialization-local-const/output-client.js	Added expected import and registration calls for Circle, Rectangle, and Triangle classes
packages/swc-plugin-workflow/transform/tests/fixture/custom-serialization-imported/output-client.js	Added expected import and registration calls for Color and Vector classes
packages/swc-plugin-workflow/transform/tests/errors/instance-methods/output-client.js	Added expected import and registration call for TestClass
.changeset/modern-clubs-own.md	Added changeset documenting this patch change

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[ijjk]

Seems good but the deduplication callout from copilot does seem good as well

[github-actions]

📊 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	🥇 Next.js (Turbopack)	0.041s (-16.4% 🟢)	1.019s (~)	0.978s	10	1.00x
💻 Local	Express	0.043s (-1.6%)	1.008s (-1.3%)	0.965s	10	1.04x
💻 Local	Nitro	0.043s (-11.1% 🟢)	1.007s (~)	0.964s	10	1.06x
🐘 Postgres	Express	0.127s (-48.6% 🟢)	1.015s (~)	0.888s	10	3.10x
🐘 Postgres	Nitro	0.162s (-60.9% 🟢)	1.026s (+1.2%)	0.864s	10	3.96x
🐘 Postgres	Next.js (Turbopack)	0.242s (+100.4% 🔺)	1.021s (~)	0.778s	10	5.93x

▲ Production (Vercel)

World	Framework	Workflow Time	Wall Time	Overhead	Samples	vs Fastest
▲ Vercel	🥇 Nitro	0.596s (-11.7% 🟢)	1.698s (+12.3% 🔺)	1.101s	10	1.00x
▲ Vercel	Express	0.629s (-18.0% 🟢)	1.601s (-5.4% 🟢)	0.972s	10	1.05x
▲ Vercel	Next.js (Turbopack)	0.695s (-17.4% 🟢)	1.553s (-9.9% 🟢)	0.858s	10	1.17x

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

workflow with 1 step

💻 Local Development

World	Framework	Workflow Time	Wall Time	Overhead	Samples	vs Fastest
💻 Local	🥇 Next.js (Turbopack)	1.103s (~)	2.012s (~)	0.909s	10	1.00x
💻 Local	Express	1.116s (~)	2.008s (~)	0.892s	10	1.01x
💻 Local	Nitro	1.118s (~)	2.007s (~)	0.889s	10	1.01x
🐘 Postgres	Next.js (Turbopack)	2.254s (+17.5% 🔺)	3.019s (+49.8% 🔺)	0.765s	10	2.04x
🐘 Postgres	Express	2.472s (+17.8% 🔺)	3.013s (~)	0.541s	10	2.24x
🐘 Postgres	Nitro	2.473s (+9.2% 🔺)	3.014s (~)	0.542s	10	2.24x

▲ Production (Vercel)

World	Framework	Workflow Time	Wall Time	Overhead	Samples	vs Fastest
▲ Vercel	🥇 Express	2.730s (-1.8%)	3.744s (+3.0%)	1.013s	10	1.00x
▲ Vercel	Nitro	2.874s (~)	3.779s (+4.6%)	0.905s	10	1.05x
▲ Vercel	Next.js (Turbopack)	2.952s (+1.5%)	3.663s (-0.7%)	0.711s	10	1.08x

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

workflow with 10 sequential steps

💻 Local Development

World	Framework	Workflow Time	Wall Time	Overhead	Samples	vs Fastest
💻 Local	🥇 Next.js (Turbopack)	10.716s (~)	11.018s (~)	0.302s	5	1.00x
💻 Local	Nitro	10.841s (~)	11.014s (~)	0.173s	5	1.01x
💻 Local	Express	10.852s (~)	11.013s (~)	0.161s	5	1.01x
🐘 Postgres	Nitro	20.292s (+0.6%)	21.041s (~)	0.750s	5	1.89x
🐘 Postgres	Express	20.310s (+30.5% 🔺)	21.037s (+31.2% 🔺)	0.726s	5	1.90x
🐘 Postgres	Next.js (Turbopack)	20.354s (+40.4% 🔺)	21.043s (+39.9% 🔺)	0.689s	5	1.90x

▲ Production (Vercel)

World	Framework	Workflow Time	Wall Time	Overhead	Samples	vs Fastest
▲ Vercel	🥇 Nitro	22.236s (-6.6% 🟢)	23.066s (-5.8% 🟢)	0.830s	5	1.00x
▲ Vercel	Express	22.515s (-6.9% 🟢)	23.414s (-6.1% 🟢)	0.898s	5	1.01x
▲ Vercel	Next.js (Turbopack)	22.838s (~)	23.452s (-1.4%)	0.614s	5	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
💻 Local	🥇 Next.js (Turbopack)	1.389s (~)	2.012s (~)	0.622s	15	1.00x
💻 Local	Nitro	1.413s (~)	2.007s (~)	0.594s	15	1.02x
💻 Local	Express	1.414s (-0.8%)	2.007s (~)	0.593s	15	1.02x
🐘 Postgres	Next.js (Turbopack)	2.200s (+3.3%)	2.853s (+5.3% 🔺)	0.653s	11	1.58x
🐘 Postgres	Nitro	2.305s (-4.9%)	2.678s (-11.0% 🟢)	0.373s	12	1.66x
🐘 Postgres	Express	2.515s (+21.3% 🔺)	3.014s (+16.0% 🔺)	0.499s	10	1.81x

▲ Production (Vercel)

World	Framework	Workflow Time	Wall Time	Overhead	Samples	vs Fastest
▲ Vercel	🥇 Next.js (Turbopack)	3.000s (-3.5%)	3.773s (-5.5% 🟢)	0.773s	8	1.00x
▲ Vercel	Nitro	3.406s (+7.1% 🔺)	4.360s (+11.9% 🔺)	0.954s	7	1.14x
▲ Vercel	Express	3.551s (+21.7% 🔺)	4.414s (+16.5% 🔺)	0.863s	7	1.18x

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

Promise.all with 25 concurrent steps

💻 Local Development

World	Framework	Workflow Time	Wall Time	Overhead	Samples	vs Fastest
💻 Local	🥇 Next.js (Turbopack)	2.472s (~)	3.066s (-4.3%)	0.594s	10	1.00x
💻 Local	Express	2.502s (-2.0%)	3.029s (+0.5%)	0.527s	10	1.01x
💻 Local	Nitro	2.510s (-2.1%)	3.026s (~)	0.515s	10	1.02x
🐘 Postgres	Express	7.934s (-20.5% 🟢)	8.305s (-20.5% 🟢)	0.371s	4	3.21x
🐘 Postgres	Nitro	8.839s (+18.5% 🔺)	9.274s (+14.9% 🔺)	0.435s	4	3.58x
🐘 Postgres	Next.js (Turbopack)	11.559s (-0.8%)	12.037s (-0.7%)	0.478s	3	4.68x

▲ Production (Vercel)

World	Framework	Workflow Time	Wall Time	Overhead	Samples	vs Fastest
▲ Vercel	🥇 Next.js (Turbopack)	3.235s (-6.5% 🟢)	4.052s (-0.7%)	0.817s	8	1.00x
▲ Vercel	Express	3.374s (+2.4%)	4.168s (+2.8%)	0.795s	8	1.04x
▲ Vercel	Nitro	3.535s (+15.7% 🔺)	4.228s (+10.6% 🔺)	0.694s	8	1.09x

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

Promise.race with 10 concurrent steps

💻 Local Development

World	Framework	Workflow Time	Wall Time	Overhead	Samples	vs Fastest
💻 Local	🥇 Nitro	1.409s (-2.7%)	2.007s (~)	0.598s	15	1.00x
💻 Local	Next.js (Turbopack)	1.427s (+1.0%)	2.013s (~)	0.586s	15	1.01x
💻 Local	Express	1.434s (~)	2.006s (~)	0.572s	15	1.02x
🐘 Postgres	Nitro	1.967s (-8.0% 🟢)	2.477s (-4.7%)	0.511s	13	1.40x
🐘 Postgres	Express	2.061s (+14.5% 🔺)	2.528s (+13.3% 🔺)	0.467s	12	1.46x
🐘 Postgres	Next.js (Turbopack)	2.299s (-2.5%)	2.746s (-9.2% 🟢)	0.447s	11	1.63x

▲ Production (Vercel)

World	Framework	Workflow Time	Wall Time	Overhead	Samples	vs Fastest
▲ Vercel	🥇 Nitro	2.838s (+1.0%)	3.792s (+3.6%)	0.953s	8	1.00x
▲ Vercel	Express	2.853s (+0.9%)	3.886s (+5.3% 🔺)	1.033s	8	1.01x
▲ Vercel	Next.js (Turbopack)	3.017s (+5.7% 🔺)	4.024s (+9.6% 🔺)	1.007s	8	1.06x

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

Promise.race with 25 concurrent steps

💻 Local Development

World	Framework	Workflow Time	Wall Time	Overhead	Samples	vs Fastest
💻 Local	🥇 Next.js (Turbopack)	2.536s (~)	3.102s (+1.6%)	0.566s	10	1.00x
💻 Local	Express	2.568s (-2.8%)	3.022s (~)	0.454s	10	1.01x
💻 Local	Nitro	2.596s (-0.5%)	3.022s (~)	0.427s	10	1.02x
🐘 Postgres	Nitro	11.622s (-3.4%)	12.050s (-2.8%)	0.428s	3	4.58x
🐘 Postgres	Express	12.974s (+6.7% 🔺)	13.022s (+2.5%)	0.048s	3	5.12x
🐘 Postgres	Next.js (Turbopack)	13.121s (-5.6% 🟢)	13.705s (-4.6%)	0.584s	3	5.17x

▲ Production (Vercel)

World	Framework	Workflow Time	Wall Time	Overhead	Samples	vs Fastest
▲ Vercel	🥇 Nitro	3.089s (-21.8% 🟢)	3.948s (-18.8% 🟢)	0.859s	8	1.00x
▲ Vercel	Next.js (Turbopack)	3.263s (+4.6%)	4.032s (+6.9% 🔺)	0.769s	8	1.06x
▲ Vercel	Express	3.657s (+2.4%)	4.312s (-0.8%)	0.655s	7	1.18x

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

Stream Benchmarks(includes TTFB metrics)

workflow with stream

💻 Local Development

World	Framework	Workflow Time	TTFB	Slurp	Wall Time	Overhead	Samples	vs Fastest
💻 Local	🥇 Next.js (Turbopack)	0.144s (+1.6%)	1.004s (~)	0.016s (-12.2% 🟢)	1.027s (~)	0.884s	10	1.00x
💻 Local	Express	0.184s (-0.7%)	0.992s (~)	0.018s (+19.9% 🔺)	1.024s (~)	0.841s	10	1.28x
💻 Local	Nitro	0.188s (-0.6%)	0.993s (~)	0.015s (-2.6%)	1.022s (~)	0.834s	10	1.31x
🐘 Postgres	Next.js (Turbopack)	1.304s (+107.0% 🔺)	2.040s (+109.8% 🔺)	0.000s (NaN%)	2.120s (+108.6% 🔺)	0.816s	10	9.07x
🐘 Postgres	Nitro	1.451s (-41.4% 🟢)	2.266s (-11.6% 🟢)	0.000s (-100.0% 🟢)	2.314s (-23.2% 🟢)	0.863s	10	10.10x
🐘 Postgres	Express	2.104s (+65.2% 🔺)	2.936s (+66.6% 🔺)	0.000s (NaN%)	3.016s (+49.7% 🔺)	0.911s	10	14.64x

▲ Production (Vercel)

World	Framework	Workflow Time	TTFB	Slurp	Wall Time	Overhead	Samples	vs Fastest
▲ Vercel	🥇 Next.js (Turbopack)	2.932s (-4.8%)	3.245s (+2.3%)	0.537s (-33.6% 🟢)	4.267s (-5.6% 🟢)	1.335s	10	1.00x
▲ Vercel	Nitro	3.058s (-0.7%)	3.228s (+1.8%)	0.672s (-35.1% 🟢)	4.459s (-7.0% 🟢)	1.401s	10	1.04x
▲ Vercel	Express	3.100s (+2.6%)	3.330s (+2.9%)	0.518s (-13.5% 🟢)	4.388s (+1.7%)	1.288s	10	1.06x

🔍 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)	7/8
🐘 Postgres	Next.js (Turbopack)	3/8
▲ Vercel	Nitro	4/8

Fastest World by Framework

Winner determined by most benchmark wins

Framework	🥇 Fastest World	Wins
Express	💻 Local	8/8
Next.js (Turbopack)	💻 Local	8/8
Nitro	💻 Local	8/8

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)

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📋 View full workflow run

[vercel]

🔧 Build Fix:

The OpenAI class is not constructable in the imported module. This is a type error where the code is trying to instantiate the OpenAI class, but the module export doesn't provide a constructor signature.