fix(world-local): prevent path traversal via request-supplied IDs

[TooTallNate]

Summary

• Request-supplied identifiers (runId, eventId, stepId, hookId, correlationId, stream names, and tags) flowed straight into path.join() inside @workflow/world-local, so a client could send a payload like {"runId":"../../../package"} to /.well-known/workflow/v1/flow and read or write files outside the workflow data directory.
• Added a centralized assertSafeEntityId helper in packages/world-local/src/fs.ts that rejects IDs which are empty, start with ., or contain /, \, or NUL bytes. This is permissive enough to accept every existing valid ID shape (ULIDs, composite keys like wrun_X-step_Y, base64url stream namespaces, tags like vitest-0) while blocking real traversal vectors.
• Applied the check at each storage-layer entry point that composes IDs into filesystem paths: fs.taggedPath / readJSONWithFallback / paginatedFileSystemQuery, the runs / steps / events / hooks storage methods, and the streamer.

Test plan

• pnpm --filter @workflow/world-local test — 266 → 328 passing (62 new unit + integration tests covering the exact payloads from the report: ../../../package, ../runs/wrun_…, backslash variants, NUL bytes, .locks, etc.)
• pnpm --filter @workflow/core test — 591 passing

[changeset-bot]

🦋 Changeset detected

Latest commit: 8d3898a

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

This PR includes changesets to release 19 packages

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

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Project	Deployment	Actions	Updated (UTC)
example-nextjs-workflow-turbopack	Ready	Preview, Comment	Apr 30, 2026 8:43am
example-nextjs-workflow-webpack	Ready	Preview, Comment	Apr 30, 2026 8:43am
example-workflow	Ready	Preview, Comment	Apr 30, 2026 8:43am
workbench-astro-workflow	Ready	Preview, Comment	Apr 30, 2026 8:43am
workbench-express-workflow	Ready	Preview, Comment	Apr 30, 2026 8:43am
workbench-fastify-workflow	Ready	Preview, Comment	Apr 30, 2026 8:43am
workbench-hono-workflow	Ready	Preview, Comment	Apr 30, 2026 8:43am
workbench-nitro-workflow	Ready	Preview, Comment	Apr 30, 2026 8:43am
workbench-nuxt-workflow	Ready	Preview, Comment	Apr 30, 2026 8:43am
workbench-sveltekit-workflow	Ready	Preview, Comment	Apr 30, 2026 8:43am
workbench-vite-workflow	Ready	Preview, Comment	Apr 30, 2026 8:43am
workflow-docs	Ready	Preview, Comment, Open in v0	Apr 30, 2026 8:43am
workflow-swc-playground	Ready	Preview, Comment	Apr 30, 2026 8:43am
workflow-web	Ready	Preview, Comment	Apr 30, 2026 8:43am

[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	🥇 Nitro	0.044s (+2.1%)	1.005s (~)	0.961s	10	1.00x
💻 Local	Express	0.044s (~)	1.005s (~)	0.961s	10	1.00x
🐘 Postgres	Express	0.049s (-15.0% 🟢)	1.009s (~)	0.960s	10	1.12x
🐘 Postgres	Nitro	0.057s (-40.5% 🟢)	1.010s (-3.2%)	0.953s	10	1.29x

workflow with 1 step

💻 Local Development

World	Framework	Workflow Time	Wall Time	Overhead	Samples	vs Fastest
🐘 Postgres	🥇 Express	1.120s (-2.3%)	2.009s (~)	0.889s	10	1.00x
💻 Local	Express	1.126s (~)	2.005s (~)	0.880s	10	1.01x
💻 Local	Nitro	1.129s (~)	2.006s (~)	0.876s	10	1.01x
🐘 Postgres	Nitro	1.135s (~)	2.009s (~)	0.874s	10	1.01x

workflow with 10 sequential steps

💻 Local Development

World	Framework	Workflow Time	Wall Time	Overhead	Samples	vs Fastest
🐘 Postgres	🥇 Express	10.691s (-2.5%)	11.018s (~)	0.327s	3	1.00x
🐘 Postgres	Nitro	10.886s (~)	11.018s (~)	0.132s	3	1.02x
💻 Local	Express	10.937s (~)	11.023s (~)	0.086s	3	1.02x
💻 Local	Nitro	10.947s (~)	11.023s (~)	0.076s	3	1.02x

workflow with 25 sequential steps

💻 Local Development

World	Framework	Workflow Time	Wall Time	Overhead	Samples	vs Fastest
🐘 Postgres	🥇 Express	13.971s (-4.2%)	14.021s (-6.7% 🟢)	0.050s	5	1.00x
🐘 Postgres	Nitro	14.494s (-0.7%)	15.019s (~)	0.525s	4	1.04x
💻 Local	Nitro	14.982s (-0.5%)	15.280s (-4.7%)	0.298s	4	1.07x
💻 Local	Express	14.995s (~)	15.029s (~)	0.034s	4	1.07x

workflow with 50 sequential steps

💻 Local Development

World	Framework	Workflow Time	Wall Time	Overhead	Samples	vs Fastest
🐘 Postgres	🥇 Express	12.932s (-7.7% 🟢)	13.021s (-10.8% 🟢)	0.089s	7	1.00x
🐘 Postgres	Nitro	13.814s (-1.1%)	14.020s (-2.0%)	0.206s	7	1.07x
💻 Local	Nitro	16.416s (-2.2%)	17.031s (~)	0.614s	6	1.27x
💻 Local	Express	16.689s (+0.5%)	17.030s (~)	0.341s	6	1.29x

Promise.all with 10 concurrent steps

💻 Local Development

World	Framework	Workflow Time	Wall Time	Overhead	Samples	vs Fastest
🐘 Postgres	🥇 Express	1.196s (-5.1% 🟢)	2.009s (~)	0.812s	15	1.00x
🐘 Postgres	Nitro	1.253s (-1.7%)	2.009s (~)	0.756s	15	1.05x
💻 Local	Nitro	1.504s (-7.8% 🟢)	2.006s (-3.3%)	0.502s	15	1.26x
💻 Local	Express	1.512s (+1.6%)	2.006s (~)	0.494s	15	1.26x

Promise.all with 25 concurrent steps

💻 Local Development

World	Framework	Workflow Time	Wall Time	Overhead	Samples	vs Fastest
🐘 Postgres	🥇 Express	2.278s (-3.5%)	3.009s (~)	0.731s	10	1.00x
🐘 Postgres	Nitro	2.338s (-0.6%)	3.010s (~)	0.673s	10	1.03x
💻 Local	Nitro	2.828s (-10.0% 🟢)	3.008s (-22.6% 🟢)	0.180s	10	1.24x
💻 Local	Express	2.958s (~)	3.208s (-7.1% 🟢)	0.250s	10	1.30x

Promise.all with 50 concurrent steps

💻 Local Development

World	Framework	Workflow Time	Wall Time	Overhead	Samples	vs Fastest
🐘 Postgres	🥇 Express	3.371s (-3.3%)	4.009s (~)	0.638s	8	1.00x
🐘 Postgres	Nitro	3.455s (-0.7%)	4.010s (~)	0.554s	8	1.03x
💻 Local	Nitro	7.405s (-11.3% 🟢)	8.020s (-11.1% 🟢)	0.614s	4	2.20x
💻 Local	Express	8.209s (-1.6%)	9.022s (~)	0.814s	4	2.44x

Promise.race with 10 concurrent steps

💻 Local Development

World	Framework	Workflow Time	Wall Time	Overhead	Samples	vs Fastest
🐘 Postgres	🥇 Express	1.199s (-4.6%)	2.007s (~)	0.808s	15	1.00x
🐘 Postgres	Nitro	1.260s (~)	2.008s (~)	0.749s	15	1.05x
💻 Local	Express	1.516s (-19.9% 🟢)	2.006s (-15.2% 🟢)	0.489s	15	1.26x
💻 Local	Nitro	1.585s (-15.1% 🟢)	2.006s (-14.3% 🟢)	0.421s	15	1.32x

Promise.race with 25 concurrent steps

💻 Local Development

World	Framework	Workflow Time	Wall Time	Overhead	Samples	vs Fastest
🐘 Postgres	🥇 Express	2.269s (-3.1%)	3.009s (~)	0.740s	10	1.00x
🐘 Postgres	Nitro	2.315s (-1.0%)	3.009s (~)	0.694s	10	1.02x
💻 Local	Nitro	2.903s (-5.3% 🟢)	3.454s (-11.1% 🟢)	0.550s	9	1.28x
💻 Local	Express	3.170s (+1.2%)	4.010s (+6.6% 🔺)	0.840s	8	1.40x

Promise.race with 50 concurrent steps

💻 Local Development

World	Framework	Workflow Time	Wall Time	Overhead	Samples	vs Fastest
🐘 Postgres	🥇 Express	3.388s (-3.2%)	4.008s (~)	0.620s	8	1.00x
🐘 Postgres	Nitro	3.476s (~)	4.009s (~)	0.533s	8	1.03x
💻 Local	Nitro	8.071s (-11.7% 🟢)	9.021s (-10.0% 🟢)	0.950s	4	2.38x
💻 Local	Express	8.942s (+1.6%)	9.276s (~)	0.335s	4	2.64x

workflow with 10 sequential data payload steps (10KB)

💻 Local Development

World	Framework	Workflow Time	Wall Time	Overhead	Samples	vs Fastest
🐘 Postgres	🥇 Express	0.587s (-30.0% 🟢)	1.006s (-1.7%)	0.419s	60	1.00x
🐘 Postgres	Nitro	0.789s (-3.8%)	1.006s (~)	0.216s	60	1.34x
💻 Local	Express	0.987s (~)	1.158s (+7.7% 🔺)	0.171s	52	1.68x
💻 Local	Nitro	1.011s (+3.1%)	1.627s (+48.7% 🔺)	0.616s	37	1.72x

workflow with 25 sequential data payload steps (10KB)

💻 Local Development

World	Framework	Workflow Time	Wall Time	Overhead	Samples	vs Fastest
🐘 Postgres	🥇 Express	1.406s (-28.9% 🟢)	2.007s (-11.1% 🟢)	0.601s	45	1.00x
🐘 Postgres	Nitro	1.886s (-2.2%)	2.030s (-3.4%)	0.144s	45	1.34x
💻 Local	Express	3.040s (+0.8%)	3.609s (+0.7%)	0.569s	25	2.16x
💻 Local	Nitro	3.048s (~)	3.729s (-0.8%)	0.681s	25	2.17x

workflow with 50 sequential data payload steps (10KB)

💻 Local Development

World	Framework	Workflow Time	Wall Time	Overhead	Samples	vs Fastest
🐘 Postgres	🥇 Express	2.926s (-26.7% 🟢)	3.137s (-28.2% 🟢)	0.210s	39	1.00x
🐘 Postgres	Nitro	3.860s (-5.9% 🟢)	4.077s (-11.4% 🟢)	0.218s	30	1.32x
💻 Local	Nitro	8.969s (-3.5%)	9.479s (-5.4% 🟢)	0.510s	13	3.06x
💻 Local	Express	9.232s (~)	9.942s (-0.8%)	0.710s	13	3.15x

workflow with 10 concurrent data payload steps (10KB)

💻 Local Development

World	Framework	Workflow Time	Wall Time	Overhead	Samples	vs Fastest
🐘 Postgres	🥇 Express	0.226s (-20.0% 🟢)	1.007s (~)	0.781s	60	1.00x
🐘 Postgres	Nitro	0.272s (-4.1%)	1.007s (~)	0.735s	60	1.20x
💻 Local	Nitro	0.551s (-8.9% 🟢)	1.004s (-1.7%)	0.454s	60	2.44x
💻 Local	Express	0.578s (+3.2%)	1.004s (~)	0.426s	60	2.56x

workflow with 25 concurrent data payload steps (10KB)

💻 Local Development

World	Framework	Workflow Time	Wall Time	Overhead	Samples	vs Fastest
🐘 Postgres	🥇 Express	0.354s (-30.5% 🟢)	1.006s (~)	0.651s	90	1.00x
🐘 Postgres	Nitro	0.484s (-2.5%)	1.007s (~)	0.523s	90	1.37x
💻 Local	Nitro	2.402s (-5.4% 🟢)	3.009s (~)	0.607s	30	6.78x
💻 Local	Express	2.564s (+2.0%)	3.009s (~)	0.445s	30	7.24x

workflow with 50 concurrent data payload steps (10KB)

💻 Local Development

World	Framework	Workflow Time	Wall Time	Overhead	Samples	vs Fastest
🐘 Postgres	🥇 Express	0.564s (-31.2% 🟢)	1.006s (-1.1%)	0.443s	120	1.00x
🐘 Postgres	Nitro	0.769s (-2.6%)	1.007s (~)	0.238s	120	1.37x
💻 Local	Nitro	10.339s (-7.6% 🟢)	11.028s (-5.5% 🟢)	0.689s	11	18.34x
💻 Local	Express	11.094s (-0.9%)	11.756s (-1.5%)	0.662s	11	19.68x

Stream Benchmarks(includes TTFB metrics)

workflow with stream

💻 Local Development

World	Framework	Workflow Time	TTFB	Slurp	Wall Time	Overhead	Samples	vs Fastest
🐘 Postgres	🥇 Express	0.153s (-25.5% 🟢)	1.000s (~)	0.001s (-31.3% 🟢)	1.009s (~)	0.856s	10	1.00x
💻 Local	Express	0.201s (+0.7%)	1.004s (~)	0.012s (+2.5%)	1.019s (~)	0.818s	10	1.31x
💻 Local	Nitro	0.205s (-3.9%)	1.004s (~)	0.010s (-20.0% 🟢)	1.016s (~)	0.810s	10	1.34x
🐘 Postgres	Nitro	0.208s (+1.6%)	0.995s (~)	0.001s (-6.7% 🟢)	1.009s (~)	0.801s	10	1.36x

stream pipeline with 5 transform steps (1MB)

💻 Local Development

World	Framework	Workflow Time	TTFB	Slurp	Wall Time	Overhead	Samples	vs Fastest
🐘 Postgres	🥇 Express	0.496s (-21.2% 🟢)	1.006s (~)	0.003s (-9.7% 🟢)	1.020s (~)	0.524s	59	1.00x
🐘 Postgres	Nitro	0.597s (-4.4%)	1.007s (~)	0.004s (-5.7% 🟢)	1.021s (~)	0.424s	59	1.20x
💻 Local	Express	0.752s (-0.6%)	1.012s (-1.6%)	0.010s (+1.5%)	1.024s (-1.6%)	0.271s	59	1.52x
💻 Local	Nitro	0.857s (+2.2%)	1.011s (~)	0.009s (-1.4%)	1.115s (~)	0.258s	54	1.73x

10 parallel streams (1MB each)

💻 Local Development

World	Framework	Workflow Time	TTFB	Slurp	Wall Time	Overhead	Samples	vs Fastest
🐘 Postgres	🥇 Express	0.903s (-6.0% 🟢)	1.109s (-13.2% 🟢)	0.000s (+25.5% 🔺)	1.118s (-14.4% 🟢)	0.215s	55	1.00x
🐘 Postgres	Nitro	0.946s (-2.3%)	1.148s (-7.9% 🟢)	0.000s (-53.8% 🟢)	1.161s (-7.7% 🟢)	0.215s	52	1.05x
💻 Local	Nitro	1.208s (-1.2%)	2.020s (~)	0.000s (+233.3% 🔺)	2.022s (~)	0.814s	30	1.34x
💻 Local	Express	1.245s (+1.6%)	2.023s (~)	0.000s (-10.0% 🟢)	2.024s (~)	0.780s	30	1.38x

fan-out fan-in 10 streams (1MB each)

💻 Local Development

World	Framework	Workflow Time	TTFB	Slurp	Wall Time	Overhead	Samples	vs Fastest
🐘 Postgres	🥇 Express	1.629s (-8.1% 🟢)	2.103s (-3.4%)	0.000s (+Infinity% 🔺)	2.112s (-3.9%)	0.483s	29	1.00x
🐘 Postgres	Nitro	1.778s (-0.7%)	2.102s (-1.8%)	0.000s (-100.0% 🟢)	2.113s (-2.8%)	0.335s	29	1.09x
💻 Local	Nitro	3.472s (+2.5%)	4.102s (+1.7%)	0.000s (-25.0% 🟢)	4.104s (+1.7%)	0.632s	15	2.13x
💻 Local	Express	3.573s (+3.1%)	4.099s (+1.6%)	0.001s (-16.7% 🟢)	4.101s (+1.6%)	0.528s	15	2.19x

Summary

Fastest Framework by World

Winner determined by most benchmark wins

World	🥇 Fastest Framework	Wins
💻 Local	Nitro	14/21
🐘 Postgres	Express	21/21

Fastest World by Framework

Winner determined by most benchmark wins

Framework	🥇 Fastest World	Wins
Express	🐘 Postgres	20/21
Nitro	🐘 Postgres	18/21

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
• 🌐 Turso: Community world (local development)
• 🌐 MongoDB: Community world (local development)
• 🌐 Redis: Community world (local development)
• 🌐 Jazz: Community world (local development)

---

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[github-actions]

🧪 E2E Test Results

✅ All tests passed

Summary

	Passed	Failed	Skipped	Total
✅ ▲ Vercel Production	989	0	67	1056
✅ 💻 Local Development	1066	0	86	1152
✅ 📦 Local Production	1066	0	86	1152
✅ 🐘 Local Postgres	1066	0	86	1152
✅ 🪟 Windows	96	0	0	96
✅ 📋 Other	270	0	18	288
Total	4553	0	343	4896

Details by Category

✅ ▲ Vercel Production

App	Passed	Failed	Skipped
✅ astro	89	0	7
✅ example	89	0	7
✅ express	89	0	7
✅ fastify	89	0	7
✅ hono	89	0	7
✅ nextjs-turbopack	94	0	2
✅ nextjs-webpack	94	0	2
✅ nitro	89	0	7
✅ nuxt	89	0	7
✅ sveltekit	89	0	7
✅ vite	89	0	7

✅ 💻 Local Development

App	Passed	Failed	Skipped
✅ astro-stable	90	0	6
✅ express-stable	90	0	6
✅ fastify-stable	90	0	6
✅ hono-stable	90	0	6
✅ nextjs-turbopack-canary	77	0	19
✅ nextjs-turbopack-stable	96	0	0
✅ nextjs-webpack-canary	77	0	19
✅ nextjs-webpack-stable	96	0	0
✅ nitro-stable	90	0	6
✅ nuxt-stable	90	0	6
✅ sveltekit-stable	90	0	6
✅ vite-stable	90	0	6

✅ 📦 Local Production

App	Passed	Failed	Skipped
✅ astro-stable	90	0	6
✅ express-stable	90	0	6
✅ fastify-stable	90	0	6
✅ hono-stable	90	0	6
✅ nextjs-turbopack-canary	77	0	19
✅ nextjs-turbopack-stable	96	0	0
✅ nextjs-webpack-canary	77	0	19
✅ nextjs-webpack-stable	96	0	0
✅ nitro-stable	90	0	6
✅ nuxt-stable	90	0	6
✅ sveltekit-stable	90	0	6
✅ vite-stable	90	0	6

✅ 🐘 Local Postgres

App	Passed	Failed	Skipped
✅ astro-stable	90	0	6
✅ express-stable	90	0	6
✅ fastify-stable	90	0	6
✅ hono-stable	90	0	6
✅ nextjs-turbopack-canary	77	0	19
✅ nextjs-turbopack-stable	96	0	0
✅ nextjs-webpack-canary	77	0	19
✅ nextjs-webpack-stable	96	0	0
✅ nitro-stable	90	0	6
✅ nuxt-stable	90	0	6
✅ sveltekit-stable	90	0	6
✅ vite-stable	90	0	6

✅ 🪟 Windows

App	Passed	Failed	Skipped
✅ nextjs-turbopack	96	0	0

✅ 📋 Other

App	Passed	Failed	Skipped
✅ e2e-local-dev-nest-stable	90	0	6
✅ e2e-local-postgres-nest-stable	90	0	6
✅ e2e-local-prod-nest-stable	90	0	6

---

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[Copilot]

Pull request overview

This PR hardens @workflow/world-local’s filesystem-backed storage against path traversal by validating request-supplied identifiers before they’re used in file paths, and adds regression tests to cover common traversal payloads.

Changes:

• Introduces assertSafeEntityId (and UnsafeEntityIdError) and applies it across filesystem path composition helpers.
• Adds ID validation at storage entry points (runs/steps/events/hooks) and streamer operations that use IDs in filenames.
• Expands unit + integration coverage to ensure traversal payloads are rejected; adds a changeset for the patch release.

Reviewed changes

Copilot reviewed 9 out of 9 changed files in this pull request and generated 5 comments.

Show a summary per file

File	Description
packages/world-local/src/fs.ts	Adds centralized ID validation + applies it in taggedPath, readJSONWithFallback, and paginatedFileSystemQuery.
packages/world-local/src/streamer.ts	Validates runId and streamName before using them as filename prefixes / keys.
packages/world-local/src/storage/runs-storage.ts	Validates runId before reading run JSON from disk.
packages/world-local/src/storage/steps-storage.ts	Validates runId/stepId before reading steps and before listing by run prefix.
packages/world-local/src/storage/events-storage.ts	Validates runId/eventId and request correlationId before composing composite keys and paths.
packages/world-local/src/storage/hooks-storage.ts	Validates hookId before reading hook JSON from disk.
packages/world-local/src/fs.test.ts	Adds focused tests for assertSafeEntityId and for validation in taggedPath/readJSONWithFallback.
packages/world-local/src/storage.test.ts	Adds regression tests ensuring traversal payloads are rejected across storage APIs.
.changeset/world-local-path-traversal.md	Declares a patch release for the security fix.

---

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[pranaygp]

Solid, well-scoped fix. Validation is applied at every entry point I could trace, tests cover the exact payloads from the Latacora report, and all 328 @workflow/world-local tests pass locally. A few non-blocking suggestions inline — mostly around defense-in-depth and error-type consistency. Copilot already flagged the docstring inaccuracies so I won't duplicate those.

One additional note not worth a line comment: legacy.ts's handleLegacyEvent uses runId in path.join directly (lines 47 and 73 — unchanged by this PR). It's safe today because the function is only called from events.create after assertSafeEntityId('runId', runId) has already run, but the function is exported and nothing in its signature documents that invariant. A one-line assertSafeEntityId('runId', runId) at the top of handleLegacyEvent would make the guarantee local to the file.

[pranaygp]

Two follow-ups not already covered in prior review rounds.

[TooTallNate]

Thanks for the review. Pushed b33b922 addressing every comment:

• UnsafeEntityIdError now extends WorkflowWorldError (with name + static is()) so it flows through the platform's normal error mapping instead of surfacing as a generic 500.
• Added resolveWithinBase(basedir, ...segments) as the belt-and-suspenders containment check, and routed every path.join-with-user-input through it (taggedPath, readJSONWithFallback, all four .locks/** sites in events-storage.ts, and the two sites in legacy.ts).
• handleLegacyEvent now re-asserts runId locally so the invariant is documented at the call site (per your top-level note) and both its path.join sites use resolveWithinBase.
• Error message values are truncated (48 chars + ellipsis) via truncateForError to limit attacker feedback.
• Removed the unused assertSafeEntityIds helper and the unreachable typeof branch.
• Fixed the docstring / example / filePrefix comment inaccuracies Copilot flagged.

Tests: 335 passing in @workflow/world-local (328 → 335, +7 for resolveWithinBase and the WorkflowWorldError hierarchy), 591 passing in @workflow/core.

[TooTallNate]

Summary

• Request-supplied identifiers (runId, eventId, stepId, hookId, correlationId, stream names, and tags) flowed straight into path.join() inside @workflow/world-local, so a client could send a payload like {"runId":"../../../package"} to /.well-known/workflow/v1/flow and read or write files outside the workflow data directory.
• Added a centralized assertSafeEntityId helper in packages/world-local/src/fs.ts that rejects IDs which are empty, start with ., or contain /, \, or NUL bytes. This is permissive enough to accept every existing valid ID shape (ULIDs, composite keys like wrun_X-step_Y, base64url stream namespaces, tags like vitest-0) while blocking real traversal vectors.
• Applied the check at each storage-layer entry point that composes IDs into filesystem paths: fs.taggedPath / readJSONWithFallback / paginatedFileSystemQuery, the runs / steps / events / hooks storage methods, and the streamer.

Test plan

• pnpm --filter @workflow/world-local test — 266 → 328 passing (62 new unit + integration tests covering the exact payloads from the report: ../../../package, ../runs/wrun_…, backslash variants, NUL bytes, .locks, etc.)
• pnpm --filter @workflow/core test — 591 passing

[changeset-bot]

🦋 Changeset detected

Latest commit: 8d3898a

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

This PR includes changesets to release 19 packages

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

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

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

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Project	Deployment	Actions	Updated (UTC)
example-nextjs-workflow-turbopack	Ready	Preview, Comment	Apr 30, 2026 8:43am
example-nextjs-workflow-webpack	Ready	Preview, Comment	Apr 30, 2026 8:43am
example-workflow	Ready	Preview, Comment	Apr 30, 2026 8:43am
workbench-astro-workflow	Ready	Preview, Comment	Apr 30, 2026 8:43am
workbench-express-workflow	Ready	Preview, Comment	Apr 30, 2026 8:43am
workbench-fastify-workflow	Ready	Preview, Comment	Apr 30, 2026 8:43am
workbench-hono-workflow	Ready	Preview, Comment	Apr 30, 2026 8:43am
workbench-nitro-workflow	Ready	Preview, Comment	Apr 30, 2026 8:43am
workbench-nuxt-workflow	Ready	Preview, Comment	Apr 30, 2026 8:43am
workbench-sveltekit-workflow	Ready	Preview, Comment	Apr 30, 2026 8:43am
workbench-vite-workflow	Ready	Preview, Comment	Apr 30, 2026 8:43am
workflow-docs	Ready	Preview, Comment, Open in v0	Apr 30, 2026 8:43am
workflow-swc-playground	Ready	Preview, Comment	Apr 30, 2026 8:43am
workflow-web	Ready	Preview, Comment	Apr 30, 2026 8:43am

[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	🥇 Nitro	0.044s (+2.1%)	1.005s (~)	0.961s	10	1.00x
💻 Local	Express	0.044s (~)	1.005s (~)	0.961s	10	1.00x
🐘 Postgres	Express	0.049s (-15.0% 🟢)	1.009s (~)	0.960s	10	1.12x
🐘 Postgres	Nitro	0.057s (-40.5% 🟢)	1.010s (-3.2%)	0.953s	10	1.29x

workflow with 1 step

💻 Local Development

World	Framework	Workflow Time	Wall Time	Overhead	Samples	vs Fastest
🐘 Postgres	🥇 Express	1.120s (-2.3%)	2.009s (~)	0.889s	10	1.00x
💻 Local	Express	1.126s (~)	2.005s (~)	0.880s	10	1.01x
💻 Local	Nitro	1.129s (~)	2.006s (~)	0.876s	10	1.01x
🐘 Postgres	Nitro	1.135s (~)	2.009s (~)	0.874s	10	1.01x

workflow with 10 sequential steps

💻 Local Development

World	Framework	Workflow Time	Wall Time	Overhead	Samples	vs Fastest
🐘 Postgres	🥇 Express	10.691s (-2.5%)	11.018s (~)	0.327s	3	1.00x
🐘 Postgres	Nitro	10.886s (~)	11.018s (~)	0.132s	3	1.02x
💻 Local	Express	10.937s (~)	11.023s (~)	0.086s	3	1.02x
💻 Local	Nitro	10.947s (~)	11.023s (~)	0.076s	3	1.02x

workflow with 25 sequential steps

💻 Local Development

World	Framework	Workflow Time	Wall Time	Overhead	Samples	vs Fastest
🐘 Postgres	🥇 Express	13.971s (-4.2%)	14.021s (-6.7% 🟢)	0.050s	5	1.00x
🐘 Postgres	Nitro	14.494s (-0.7%)	15.019s (~)	0.525s	4	1.04x
💻 Local	Nitro	14.982s (-0.5%)	15.280s (-4.7%)	0.298s	4	1.07x
💻 Local	Express	14.995s (~)	15.029s (~)	0.034s	4	1.07x

workflow with 50 sequential steps

💻 Local Development

World	Framework	Workflow Time	Wall Time	Overhead	Samples	vs Fastest
🐘 Postgres	🥇 Express	12.932s (-7.7% 🟢)	13.021s (-10.8% 🟢)	0.089s	7	1.00x
🐘 Postgres	Nitro	13.814s (-1.1%)	14.020s (-2.0%)	0.206s	7	1.07x
💻 Local	Nitro	16.416s (-2.2%)	17.031s (~)	0.614s	6	1.27x
💻 Local	Express	16.689s (+0.5%)	17.030s (~)	0.341s	6	1.29x

Promise.all with 10 concurrent steps

💻 Local Development

World	Framework	Workflow Time	Wall Time	Overhead	Samples	vs Fastest
🐘 Postgres	🥇 Express	1.196s (-5.1% 🟢)	2.009s (~)	0.812s	15	1.00x
🐘 Postgres	Nitro	1.253s (-1.7%)	2.009s (~)	0.756s	15	1.05x
💻 Local	Nitro	1.504s (-7.8% 🟢)	2.006s (-3.3%)	0.502s	15	1.26x
💻 Local	Express	1.512s (+1.6%)	2.006s (~)	0.494s	15	1.26x

Promise.all with 25 concurrent steps

💻 Local Development

World	Framework	Workflow Time	Wall Time	Overhead	Samples	vs Fastest
🐘 Postgres	🥇 Express	2.278s (-3.5%)	3.009s (~)	0.731s	10	1.00x
🐘 Postgres	Nitro	2.338s (-0.6%)	3.010s (~)	0.673s	10	1.03x
💻 Local	Nitro	2.828s (-10.0% 🟢)	3.008s (-22.6% 🟢)	0.180s	10	1.24x
💻 Local	Express	2.958s (~)	3.208s (-7.1% 🟢)	0.250s	10	1.30x

Promise.all with 50 concurrent steps

💻 Local Development

World	Framework	Workflow Time	Wall Time	Overhead	Samples	vs Fastest
🐘 Postgres	🥇 Express	3.371s (-3.3%)	4.009s (~)	0.638s	8	1.00x
🐘 Postgres	Nitro	3.455s (-0.7%)	4.010s (~)	0.554s	8	1.03x
💻 Local	Nitro	7.405s (-11.3% 🟢)	8.020s (-11.1% 🟢)	0.614s	4	2.20x
💻 Local	Express	8.209s (-1.6%)	9.022s (~)	0.814s	4	2.44x

Promise.race with 10 concurrent steps

💻 Local Development

World	Framework	Workflow Time	Wall Time	Overhead	Samples	vs Fastest
🐘 Postgres	🥇 Express	1.199s (-4.6%)	2.007s (~)	0.808s	15	1.00x
🐘 Postgres	Nitro	1.260s (~)	2.008s (~)	0.749s	15	1.05x
💻 Local	Express	1.516s (-19.9% 🟢)	2.006s (-15.2% 🟢)	0.489s	15	1.26x
💻 Local	Nitro	1.585s (-15.1% 🟢)	2.006s (-14.3% 🟢)	0.421s	15	1.32x

Promise.race with 25 concurrent steps

💻 Local Development

World	Framework	Workflow Time	Wall Time	Overhead	Samples	vs Fastest
🐘 Postgres	🥇 Express	2.269s (-3.1%)	3.009s (~)	0.740s	10	1.00x
🐘 Postgres	Nitro	2.315s (-1.0%)	3.009s (~)	0.694s	10	1.02x
💻 Local	Nitro	2.903s (-5.3% 🟢)	3.454s (-11.1% 🟢)	0.550s	9	1.28x
💻 Local	Express	3.170s (+1.2%)	4.010s (+6.6% 🔺)	0.840s	8	1.40x

Promise.race with 50 concurrent steps

💻 Local Development

World	Framework	Workflow Time	Wall Time	Overhead	Samples	vs Fastest
🐘 Postgres	🥇 Express	3.388s (-3.2%)	4.008s (~)	0.620s	8	1.00x
🐘 Postgres	Nitro	3.476s (~)	4.009s (~)	0.533s	8	1.03x
💻 Local	Nitro	8.071s (-11.7% 🟢)	9.021s (-10.0% 🟢)	0.950s	4	2.38x
💻 Local	Express	8.942s (+1.6%)	9.276s (~)	0.335s	4	2.64x

workflow with 10 sequential data payload steps (10KB)

💻 Local Development

World	Framework	Workflow Time	Wall Time	Overhead	Samples	vs Fastest
🐘 Postgres	🥇 Express	0.587s (-30.0% 🟢)	1.006s (-1.7%)	0.419s	60	1.00x
🐘 Postgres	Nitro	0.789s (-3.8%)	1.006s (~)	0.216s	60	1.34x
💻 Local	Express	0.987s (~)	1.158s (+7.7% 🔺)	0.171s	52	1.68x
💻 Local	Nitro	1.011s (+3.1%)	1.627s (+48.7% 🔺)	0.616s	37	1.72x

workflow with 25 sequential data payload steps (10KB)

💻 Local Development

World	Framework	Workflow Time	Wall Time	Overhead	Samples	vs Fastest
🐘 Postgres	🥇 Express	1.406s (-28.9% 🟢)	2.007s (-11.1% 🟢)	0.601s	45	1.00x
🐘 Postgres	Nitro	1.886s (-2.2%)	2.030s (-3.4%)	0.144s	45	1.34x
💻 Local	Express	3.040s (+0.8%)	3.609s (+0.7%)	0.569s	25	2.16x
💻 Local	Nitro	3.048s (~)	3.729s (-0.8%)	0.681s	25	2.17x

workflow with 50 sequential data payload steps (10KB)

💻 Local Development

World	Framework	Workflow Time	Wall Time	Overhead	Samples	vs Fastest
🐘 Postgres	🥇 Express	2.926s (-26.7% 🟢)	3.137s (-28.2% 🟢)	0.210s	39	1.00x
🐘 Postgres	Nitro	3.860s (-5.9% 🟢)	4.077s (-11.4% 🟢)	0.218s	30	1.32x
💻 Local	Nitro	8.969s (-3.5%)	9.479s (-5.4% 🟢)	0.510s	13	3.06x
💻 Local	Express	9.232s (~)	9.942s (-0.8%)	0.710s	13	3.15x

workflow with 10 concurrent data payload steps (10KB)

💻 Local Development

World	Framework	Workflow Time	Wall Time	Overhead	Samples	vs Fastest
🐘 Postgres	🥇 Express	0.226s (-20.0% 🟢)	1.007s (~)	0.781s	60	1.00x
🐘 Postgres	Nitro	0.272s (-4.1%)	1.007s (~)	0.735s	60	1.20x
💻 Local	Nitro	0.551s (-8.9% 🟢)	1.004s (-1.7%)	0.454s	60	2.44x
💻 Local	Express	0.578s (+3.2%)	1.004s (~)	0.426s	60	2.56x

workflow with 25 concurrent data payload steps (10KB)

💻 Local Development

World	Framework	Workflow Time	Wall Time	Overhead	Samples	vs Fastest
🐘 Postgres	🥇 Express	0.354s (-30.5% 🟢)	1.006s (~)	0.651s	90	1.00x
🐘 Postgres	Nitro	0.484s (-2.5%)	1.007s (~)	0.523s	90	1.37x
💻 Local	Nitro	2.402s (-5.4% 🟢)	3.009s (~)	0.607s	30	6.78x
💻 Local	Express	2.564s (+2.0%)	3.009s (~)	0.445s	30	7.24x

workflow with 50 concurrent data payload steps (10KB)

💻 Local Development

World	Framework	Workflow Time	Wall Time	Overhead	Samples	vs Fastest
🐘 Postgres	🥇 Express	0.564s (-31.2% 🟢)	1.006s (-1.1%)	0.443s	120	1.00x
🐘 Postgres	Nitro	0.769s (-2.6%)	1.007s (~)	0.238s	120	1.37x
💻 Local	Nitro	10.339s (-7.6% 🟢)	11.028s (-5.5% 🟢)	0.689s	11	18.34x
💻 Local	Express	11.094s (-0.9%)	11.756s (-1.5%)	0.662s	11	19.68x

Stream Benchmarks(includes TTFB metrics)

workflow with stream

💻 Local Development

World	Framework	Workflow Time	TTFB	Slurp	Wall Time	Overhead	Samples	vs Fastest
🐘 Postgres	🥇 Express	0.153s (-25.5% 🟢)	1.000s (~)	0.001s (-31.3% 🟢)	1.009s (~)	0.856s	10	1.00x
💻 Local	Express	0.201s (+0.7%)	1.004s (~)	0.012s (+2.5%)	1.019s (~)	0.818s	10	1.31x
💻 Local	Nitro	0.205s (-3.9%)	1.004s (~)	0.010s (-20.0% 🟢)	1.016s (~)	0.810s	10	1.34x
🐘 Postgres	Nitro	0.208s (+1.6%)	0.995s (~)	0.001s (-6.7% 🟢)	1.009s (~)	0.801s	10	1.36x

stream pipeline with 5 transform steps (1MB)

💻 Local Development

World	Framework	Workflow Time	TTFB	Slurp	Wall Time	Overhead	Samples	vs Fastest
🐘 Postgres	🥇 Express	0.496s (-21.2% 🟢)	1.006s (~)	0.003s (-9.7% 🟢)	1.020s (~)	0.524s	59	1.00x
🐘 Postgres	Nitro	0.597s (-4.4%)	1.007s (~)	0.004s (-5.7% 🟢)	1.021s (~)	0.424s	59	1.20x
💻 Local	Express	0.752s (-0.6%)	1.012s (-1.6%)	0.010s (+1.5%)	1.024s (-1.6%)	0.271s	59	1.52x
💻 Local	Nitro	0.857s (+2.2%)	1.011s (~)	0.009s (-1.4%)	1.115s (~)	0.258s	54	1.73x

10 parallel streams (1MB each)

💻 Local Development

World	Framework	Workflow Time	TTFB	Slurp	Wall Time	Overhead	Samples	vs Fastest
🐘 Postgres	🥇 Express	0.903s (-6.0% 🟢)	1.109s (-13.2% 🟢)	0.000s (+25.5% 🔺)	1.118s (-14.4% 🟢)	0.215s	55	1.00x
🐘 Postgres	Nitro	0.946s (-2.3%)	1.148s (-7.9% 🟢)	0.000s (-53.8% 🟢)	1.161s (-7.7% 🟢)	0.215s	52	1.05x
💻 Local	Nitro	1.208s (-1.2%)	2.020s (~)	0.000s (+233.3% 🔺)	2.022s (~)	0.814s	30	1.34x
💻 Local	Express	1.245s (+1.6%)	2.023s (~)	0.000s (-10.0% 🟢)	2.024s (~)	0.780s	30	1.38x

fan-out fan-in 10 streams (1MB each)

💻 Local Development

World	Framework	Workflow Time	TTFB	Slurp	Wall Time	Overhead	Samples	vs Fastest
🐘 Postgres	🥇 Express	1.629s (-8.1% 🟢)	2.103s (-3.4%)	0.000s (+Infinity% 🔺)	2.112s (-3.9%)	0.483s	29	1.00x
🐘 Postgres	Nitro	1.778s (-0.7%)	2.102s (-1.8%)	0.000s (-100.0% 🟢)	2.113s (-2.8%)	0.335s	29	1.09x
💻 Local	Nitro	3.472s (+2.5%)	4.102s (+1.7%)	0.000s (-25.0% 🟢)	4.104s (+1.7%)	0.632s	15	2.13x
💻 Local	Express	3.573s (+3.1%)	4.099s (+1.6%)	0.001s (-16.7% 🟢)	4.101s (+1.6%)	0.528s	15	2.19x

Summary

Fastest Framework by World

Winner determined by most benchmark wins

World	🥇 Fastest Framework	Wins
💻 Local	Nitro	14/21
🐘 Postgres	Express	21/21

Fastest World by Framework

Winner determined by most benchmark wins

Framework	🥇 Fastest World	Wins
Express	🐘 Postgres	20/21
Nitro	🐘 Postgres	18/21

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
• 🌐 Turso: Community world (local development)
• 🌐 MongoDB: Community world (local development)
• 🌐 Redis: Community world (local development)
• 🌐 Jazz: Community world (local development)

---

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[github-actions]

🧪 E2E Test Results

✅ All tests passed

Summary

	Passed	Failed	Skipped	Total
✅ ▲ Vercel Production	989	0	67	1056
✅ 💻 Local Development	1066	0	86	1152
✅ 📦 Local Production	1066	0	86	1152
✅ 🐘 Local Postgres	1066	0	86	1152
✅ 🪟 Windows	96	0	0	96
✅ 📋 Other	270	0	18	288
Total	4553	0	343	4896

Details by Category

✅ ▲ Vercel Production

App	Passed	Failed	Skipped
✅ astro	89	0	7
✅ example	89	0	7
✅ express	89	0	7
✅ fastify	89	0	7
✅ hono	89	0	7
✅ nextjs-turbopack	94	0	2
✅ nextjs-webpack	94	0	2
✅ nitro	89	0	7
✅ nuxt	89	0	7
✅ sveltekit	89	0	7
✅ vite	89	0	7

✅ 💻 Local Development

App	Passed	Failed	Skipped
✅ astro-stable	90	0	6
✅ express-stable	90	0	6
✅ fastify-stable	90	0	6
✅ hono-stable	90	0	6
✅ nextjs-turbopack-canary	77	0	19
✅ nextjs-turbopack-stable	96	0	0
✅ nextjs-webpack-canary	77	0	19
✅ nextjs-webpack-stable	96	0	0
✅ nitro-stable	90	0	6
✅ nuxt-stable	90	0	6
✅ sveltekit-stable	90	0	6
✅ vite-stable	90	0	6

✅ 📦 Local Production

App	Passed	Failed	Skipped
✅ astro-stable	90	0	6
✅ express-stable	90	0	6
✅ fastify-stable	90	0	6
✅ hono-stable	90	0	6
✅ nextjs-turbopack-canary	77	0	19
✅ nextjs-turbopack-stable	96	0	0
✅ nextjs-webpack-canary	77	0	19
✅ nextjs-webpack-stable	96	0	0
✅ nitro-stable	90	0	6
✅ nuxt-stable	90	0	6
✅ sveltekit-stable	90	0	6
✅ vite-stable	90	0	6

✅ 🐘 Local Postgres

App	Passed	Failed	Skipped
✅ astro-stable	90	0	6
✅ express-stable	90	0	6
✅ fastify-stable	90	0	6
✅ hono-stable	90	0	6
✅ nextjs-turbopack-canary	77	0	19
✅ nextjs-turbopack-stable	96	0	0
✅ nextjs-webpack-canary	77	0	19
✅ nextjs-webpack-stable	96	0	0
✅ nitro-stable	90	0	6
✅ nuxt-stable	90	0	6
✅ sveltekit-stable	90	0	6
✅ vite-stable	90	0	6

✅ 🪟 Windows

App	Passed	Failed	Skipped
✅ nextjs-turbopack	96	0	0

✅ 📋 Other

App	Passed	Failed	Skipped
✅ e2e-local-dev-nest-stable	90	0	6
✅ e2e-local-postgres-nest-stable	90	0	6
✅ e2e-local-prod-nest-stable	90	0	6

---

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[Copilot]

Pull request overview

This PR hardens @workflow/world-local’s filesystem-backed storage against path traversal by validating request-supplied identifiers before they’re used in file paths, and adds regression tests to cover common traversal payloads.

Changes:

• Introduces assertSafeEntityId (and UnsafeEntityIdError) and applies it across filesystem path composition helpers.
• Adds ID validation at storage entry points (runs/steps/events/hooks) and streamer operations that use IDs in filenames.
• Expands unit + integration coverage to ensure traversal payloads are rejected; adds a changeset for the patch release.

Reviewed changes

Copilot reviewed 9 out of 9 changed files in this pull request and generated 5 comments.

Show a summary per file

File	Description
packages/world-local/src/fs.ts	Adds centralized ID validation + applies it in taggedPath, readJSONWithFallback, and paginatedFileSystemQuery.
packages/world-local/src/streamer.ts	Validates runId and streamName before using them as filename prefixes / keys.
packages/world-local/src/storage/runs-storage.ts	Validates runId before reading run JSON from disk.
packages/world-local/src/storage/steps-storage.ts	Validates runId/stepId before reading steps and before listing by run prefix.
packages/world-local/src/storage/events-storage.ts	Validates runId/eventId and request correlationId before composing composite keys and paths.
packages/world-local/src/storage/hooks-storage.ts	Validates hookId before reading hook JSON from disk.
packages/world-local/src/fs.test.ts	Adds focused tests for assertSafeEntityId and for validation in taggedPath/readJSONWithFallback.
packages/world-local/src/storage.test.ts	Adds regression tests ensuring traversal payloads are rejected across storage APIs.
.changeset/world-local-path-traversal.md	Declares a patch release for the security fix.

---

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[pranaygp]

Solid, well-scoped fix. Validation is applied at every entry point I could trace, tests cover the exact payloads from the Latacora report, and all 328 @workflow/world-local tests pass locally. A few non-blocking suggestions inline — mostly around defense-in-depth and error-type consistency. Copilot already flagged the docstring inaccuracies so I won't duplicate those.

One additional note not worth a line comment: legacy.ts's handleLegacyEvent uses runId in path.join directly (lines 47 and 73 — unchanged by this PR). It's safe today because the function is only called from events.create after assertSafeEntityId('runId', runId) has already run, but the function is exported and nothing in its signature documents that invariant. A one-line assertSafeEntityId('runId', runId) at the top of handleLegacyEvent would make the guarantee local to the file.

[pranaygp]

Two follow-ups not already covered in prior review rounds.

[TooTallNate]

Thanks for the review. Pushed b33b922 addressing every comment:

• UnsafeEntityIdError now extends WorkflowWorldError (with name + static is()) so it flows through the platform's normal error mapping instead of surfacing as a generic 500.
• Added resolveWithinBase(basedir, ...segments) as the belt-and-suspenders containment check, and routed every path.join-with-user-input through it (taggedPath, readJSONWithFallback, all four .locks/** sites in events-storage.ts, and the two sites in legacy.ts).
• handleLegacyEvent now re-asserts runId locally so the invariant is documented at the call site (per your top-level note) and both its path.join sites use resolveWithinBase.
• Error message values are truncated (48 chars + ellipsis) via truncateForError to limit attacker feedback.
• Removed the unused assertSafeEntityIds helper and the unreachable typeof branch.
• Fixed the docstring / example / filePrefix comment inaccuracies Copilot flagged.

Tests: 335 passing in @workflow/world-local (328 → 335, +7 for resolveWithinBase and the WorkflowWorldError hierarchy), 591 passing in @workflow/core.

[TooTallNate]

Summary

• Request-supplied identifiers (runId, eventId, stepId, hookId, correlationId, stream names, and tags) flowed straight into path.join() inside @workflow/world-local, so a client could send a payload like {"runId":"../../../package"} to /.well-known/workflow/v1/flow and read or write files outside the workflow data directory.
• Added a centralized assertSafeEntityId helper in packages/world-local/src/fs.ts that rejects IDs which are empty, start with ., or contain /, \, or NUL bytes. This is permissive enough to accept every existing valid ID shape (ULIDs, composite keys like wrun_X-step_Y, base64url stream namespaces, tags like vitest-0) while blocking real traversal vectors.
• Applied the check at each storage-layer entry point that composes IDs into filesystem paths: fs.taggedPath / readJSONWithFallback / paginatedFileSystemQuery, the runs / steps / events / hooks storage methods, and the streamer.

Test plan

• pnpm --filter @workflow/world-local test — 266 → 328 passing (62 new unit + integration tests covering the exact payloads from the report: ../../../package, ../runs/wrun_…, backslash variants, NUL bytes, .locks, etc.)
• pnpm --filter @workflow/core test — 591 passing

[changeset-bot]

🦋 Changeset detected

Latest commit: 8d3898a

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

This PR includes changesets to release 19 packages

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

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

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

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Project	Deployment	Actions	Updated (UTC)
example-nextjs-workflow-turbopack	Ready	Preview, Comment	Apr 30, 2026 8:43am
example-nextjs-workflow-webpack	Ready	Preview, Comment	Apr 30, 2026 8:43am
example-workflow	Ready	Preview, Comment	Apr 30, 2026 8:43am
workbench-astro-workflow	Ready	Preview, Comment	Apr 30, 2026 8:43am
workbench-express-workflow	Ready	Preview, Comment	Apr 30, 2026 8:43am
workbench-fastify-workflow	Ready	Preview, Comment	Apr 30, 2026 8:43am
workbench-hono-workflow	Ready	Preview, Comment	Apr 30, 2026 8:43am
workbench-nitro-workflow	Ready	Preview, Comment	Apr 30, 2026 8:43am
workbench-nuxt-workflow	Ready	Preview, Comment	Apr 30, 2026 8:43am
workbench-sveltekit-workflow	Ready	Preview, Comment	Apr 30, 2026 8:43am
workbench-vite-workflow	Ready	Preview, Comment	Apr 30, 2026 8:43am
workflow-docs	Ready	Preview, Comment, Open in v0	Apr 30, 2026 8:43am
workflow-swc-playground	Ready	Preview, Comment	Apr 30, 2026 8:43am
workflow-web	Ready	Preview, Comment	Apr 30, 2026 8:43am

[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	🥇 Nitro	0.044s (+2.1%)	1.005s (~)	0.961s	10	1.00x
💻 Local	Express	0.044s (~)	1.005s (~)	0.961s	10	1.00x
🐘 Postgres	Express	0.049s (-15.0% 🟢)	1.009s (~)	0.960s	10	1.12x
🐘 Postgres	Nitro	0.057s (-40.5% 🟢)	1.010s (-3.2%)	0.953s	10	1.29x

workflow with 1 step

💻 Local Development

World	Framework	Workflow Time	Wall Time	Overhead	Samples	vs Fastest
🐘 Postgres	🥇 Express	1.120s (-2.3%)	2.009s (~)	0.889s	10	1.00x
💻 Local	Express	1.126s (~)	2.005s (~)	0.880s	10	1.01x
💻 Local	Nitro	1.129s (~)	2.006s (~)	0.876s	10	1.01x
🐘 Postgres	Nitro	1.135s (~)	2.009s (~)	0.874s	10	1.01x

workflow with 10 sequential steps

💻 Local Development

World	Framework	Workflow Time	Wall Time	Overhead	Samples	vs Fastest
🐘 Postgres	🥇 Express	10.691s (-2.5%)	11.018s (~)	0.327s	3	1.00x
🐘 Postgres	Nitro	10.886s (~)	11.018s (~)	0.132s	3	1.02x
💻 Local	Express	10.937s (~)	11.023s (~)	0.086s	3	1.02x
💻 Local	Nitro	10.947s (~)	11.023s (~)	0.076s	3	1.02x

workflow with 25 sequential steps

💻 Local Development

World	Framework	Workflow Time	Wall Time	Overhead	Samples	vs Fastest
🐘 Postgres	🥇 Express	13.971s (-4.2%)	14.021s (-6.7% 🟢)	0.050s	5	1.00x
🐘 Postgres	Nitro	14.494s (-0.7%)	15.019s (~)	0.525s	4	1.04x
💻 Local	Nitro	14.982s (-0.5%)	15.280s (-4.7%)	0.298s	4	1.07x
💻 Local	Express	14.995s (~)	15.029s (~)	0.034s	4	1.07x

workflow with 50 sequential steps

💻 Local Development

World	Framework	Workflow Time	Wall Time	Overhead	Samples	vs Fastest
🐘 Postgres	🥇 Express	12.932s (-7.7% 🟢)	13.021s (-10.8% 🟢)	0.089s	7	1.00x
🐘 Postgres	Nitro	13.814s (-1.1%)	14.020s (-2.0%)	0.206s	7	1.07x
💻 Local	Nitro	16.416s (-2.2%)	17.031s (~)	0.614s	6	1.27x
💻 Local	Express	16.689s (+0.5%)	17.030s (~)	0.341s	6	1.29x

Promise.all with 10 concurrent steps

💻 Local Development

World	Framework	Workflow Time	Wall Time	Overhead	Samples	vs Fastest
🐘 Postgres	🥇 Express	1.196s (-5.1% 🟢)	2.009s (~)	0.812s	15	1.00x
🐘 Postgres	Nitro	1.253s (-1.7%)	2.009s (~)	0.756s	15	1.05x
💻 Local	Nitro	1.504s (-7.8% 🟢)	2.006s (-3.3%)	0.502s	15	1.26x
💻 Local	Express	1.512s (+1.6%)	2.006s (~)	0.494s	15	1.26x

Promise.all with 25 concurrent steps

💻 Local Development

World	Framework	Workflow Time	Wall Time	Overhead	Samples	vs Fastest
🐘 Postgres	🥇 Express	2.278s (-3.5%)	3.009s (~)	0.731s	10	1.00x
🐘 Postgres	Nitro	2.338s (-0.6%)	3.010s (~)	0.673s	10	1.03x
💻 Local	Nitro	2.828s (-10.0% 🟢)	3.008s (-22.6% 🟢)	0.180s	10	1.24x
💻 Local	Express	2.958s (~)	3.208s (-7.1% 🟢)	0.250s	10	1.30x

Promise.all with 50 concurrent steps

💻 Local Development

World	Framework	Workflow Time	Wall Time	Overhead	Samples	vs Fastest
🐘 Postgres	🥇 Express	3.371s (-3.3%)	4.009s (~)	0.638s	8	1.00x
🐘 Postgres	Nitro	3.455s (-0.7%)	4.010s (~)	0.554s	8	1.03x
💻 Local	Nitro	7.405s (-11.3% 🟢)	8.020s (-11.1% 🟢)	0.614s	4	2.20x
💻 Local	Express	8.209s (-1.6%)	9.022s (~)	0.814s	4	2.44x

Promise.race with 10 concurrent steps

💻 Local Development

World	Framework	Workflow Time	Wall Time	Overhead	Samples	vs Fastest
🐘 Postgres	🥇 Express	1.199s (-4.6%)	2.007s (~)	0.808s	15	1.00x
🐘 Postgres	Nitro	1.260s (~)	2.008s (~)	0.749s	15	1.05x
💻 Local	Express	1.516s (-19.9% 🟢)	2.006s (-15.2% 🟢)	0.489s	15	1.26x
💻 Local	Nitro	1.585s (-15.1% 🟢)	2.006s (-14.3% 🟢)	0.421s	15	1.32x

Promise.race with 25 concurrent steps

💻 Local Development

World	Framework	Workflow Time	Wall Time	Overhead	Samples	vs Fastest
🐘 Postgres	🥇 Express	2.269s (-3.1%)	3.009s (~)	0.740s	10	1.00x
🐘 Postgres	Nitro	2.315s (-1.0%)	3.009s (~)	0.694s	10	1.02x
💻 Local	Nitro	2.903s (-5.3% 🟢)	3.454s (-11.1% 🟢)	0.550s	9	1.28x
💻 Local	Express	3.170s (+1.2%)	4.010s (+6.6% 🔺)	0.840s	8	1.40x

Promise.race with 50 concurrent steps

💻 Local Development

World	Framework	Workflow Time	Wall Time	Overhead	Samples	vs Fastest
🐘 Postgres	🥇 Express	3.388s (-3.2%)	4.008s (~)	0.620s	8	1.00x
🐘 Postgres	Nitro	3.476s (~)	4.009s (~)	0.533s	8	1.03x
💻 Local	Nitro	8.071s (-11.7% 🟢)	9.021s (-10.0% 🟢)	0.950s	4	2.38x
💻 Local	Express	8.942s (+1.6%)	9.276s (~)	0.335s	4	2.64x

workflow with 10 sequential data payload steps (10KB)

💻 Local Development

World	Framework	Workflow Time	Wall Time	Overhead	Samples	vs Fastest
🐘 Postgres	🥇 Express	0.587s (-30.0% 🟢)	1.006s (-1.7%)	0.419s	60	1.00x
🐘 Postgres	Nitro	0.789s (-3.8%)	1.006s (~)	0.216s	60	1.34x
💻 Local	Express	0.987s (~)	1.158s (+7.7% 🔺)	0.171s	52	1.68x
💻 Local	Nitro	1.011s (+3.1%)	1.627s (+48.7% 🔺)	0.616s	37	1.72x

workflow with 25 sequential data payload steps (10KB)

💻 Local Development

World	Framework	Workflow Time	Wall Time	Overhead	Samples	vs Fastest
🐘 Postgres	🥇 Express	1.406s (-28.9% 🟢)	2.007s (-11.1% 🟢)	0.601s	45	1.00x
🐘 Postgres	Nitro	1.886s (-2.2%)	2.030s (-3.4%)	0.144s	45	1.34x
💻 Local	Express	3.040s (+0.8%)	3.609s (+0.7%)	0.569s	25	2.16x
💻 Local	Nitro	3.048s (~)	3.729s (-0.8%)	0.681s	25	2.17x

workflow with 50 sequential data payload steps (10KB)

💻 Local Development

World	Framework	Workflow Time	Wall Time	Overhead	Samples	vs Fastest
🐘 Postgres	🥇 Express	2.926s (-26.7% 🟢)	3.137s (-28.2% 🟢)	0.210s	39	1.00x
🐘 Postgres	Nitro	3.860s (-5.9% 🟢)	4.077s (-11.4% 🟢)	0.218s	30	1.32x
💻 Local	Nitro	8.969s (-3.5%)	9.479s (-5.4% 🟢)	0.510s	13	3.06x
💻 Local	Express	9.232s (~)	9.942s (-0.8%)	0.710s	13	3.15x

workflow with 10 concurrent data payload steps (10KB)

💻 Local Development

World	Framework	Workflow Time	Wall Time	Overhead	Samples	vs Fastest
🐘 Postgres	🥇 Express	0.226s (-20.0% 🟢)	1.007s (~)	0.781s	60	1.00x
🐘 Postgres	Nitro	0.272s (-4.1%)	1.007s (~)	0.735s	60	1.20x
💻 Local	Nitro	0.551s (-8.9% 🟢)	1.004s (-1.7%)	0.454s	60	2.44x
💻 Local	Express	0.578s (+3.2%)	1.004s (~)	0.426s	60	2.56x

workflow with 25 concurrent data payload steps (10KB)

💻 Local Development

World	Framework	Workflow Time	Wall Time	Overhead	Samples	vs Fastest
🐘 Postgres	🥇 Express	0.354s (-30.5% 🟢)	1.006s (~)	0.651s	90	1.00x
🐘 Postgres	Nitro	0.484s (-2.5%)	1.007s (~)	0.523s	90	1.37x
💻 Local	Nitro	2.402s (-5.4% 🟢)	3.009s (~)	0.607s	30	6.78x
💻 Local	Express	2.564s (+2.0%)	3.009s (~)	0.445s	30	7.24x

workflow with 50 concurrent data payload steps (10KB)

💻 Local Development

World	Framework	Workflow Time	Wall Time	Overhead	Samples	vs Fastest
🐘 Postgres	🥇 Express	0.564s (-31.2% 🟢)	1.006s (-1.1%)	0.443s	120	1.00x
🐘 Postgres	Nitro	0.769s (-2.6%)	1.007s (~)	0.238s	120	1.37x
💻 Local	Nitro	10.339s (-7.6% 🟢)	11.028s (-5.5% 🟢)	0.689s	11	18.34x
💻 Local	Express	11.094s (-0.9%)	11.756s (-1.5%)	0.662s	11	19.68x

Stream Benchmarks(includes TTFB metrics)

workflow with stream

💻 Local Development

World	Framework	Workflow Time	TTFB	Slurp	Wall Time	Overhead	Samples	vs Fastest
🐘 Postgres	🥇 Express	0.153s (-25.5% 🟢)	1.000s (~)	0.001s (-31.3% 🟢)	1.009s (~)	0.856s	10	1.00x
💻 Local	Express	0.201s (+0.7%)	1.004s (~)	0.012s (+2.5%)	1.019s (~)	0.818s	10	1.31x
💻 Local	Nitro	0.205s (-3.9%)	1.004s (~)	0.010s (-20.0% 🟢)	1.016s (~)	0.810s	10	1.34x
🐘 Postgres	Nitro	0.208s (+1.6%)	0.995s (~)	0.001s (-6.7% 🟢)	1.009s (~)	0.801s	10	1.36x

stream pipeline with 5 transform steps (1MB)

💻 Local Development

World	Framework	Workflow Time	TTFB	Slurp	Wall Time	Overhead	Samples	vs Fastest
🐘 Postgres	🥇 Express	0.496s (-21.2% 🟢)	1.006s (~)	0.003s (-9.7% 🟢)	1.020s (~)	0.524s	59	1.00x
🐘 Postgres	Nitro	0.597s (-4.4%)	1.007s (~)	0.004s (-5.7% 🟢)	1.021s (~)	0.424s	59	1.20x
💻 Local	Express	0.752s (-0.6%)	1.012s (-1.6%)	0.010s (+1.5%)	1.024s (-1.6%)	0.271s	59	1.52x
💻 Local	Nitro	0.857s (+2.2%)	1.011s (~)	0.009s (-1.4%)	1.115s (~)	0.258s	54	1.73x

10 parallel streams (1MB each)

💻 Local Development

World	Framework	Workflow Time	TTFB	Slurp	Wall Time	Overhead	Samples	vs Fastest
🐘 Postgres	🥇 Express	0.903s (-6.0% 🟢)	1.109s (-13.2% 🟢)	0.000s (+25.5% 🔺)	1.118s (-14.4% 🟢)	0.215s	55	1.00x
🐘 Postgres	Nitro	0.946s (-2.3%)	1.148s (-7.9% 🟢)	0.000s (-53.8% 🟢)	1.161s (-7.7% 🟢)	0.215s	52	1.05x
💻 Local	Nitro	1.208s (-1.2%)	2.020s (~)	0.000s (+233.3% 🔺)	2.022s (~)	0.814s	30	1.34x
💻 Local	Express	1.245s (+1.6%)	2.023s (~)	0.000s (-10.0% 🟢)	2.024s (~)	0.780s	30	1.38x

fan-out fan-in 10 streams (1MB each)

💻 Local Development

World	Framework	Workflow Time	TTFB	Slurp	Wall Time	Overhead	Samples	vs Fastest
🐘 Postgres	🥇 Express	1.629s (-8.1% 🟢)	2.103s (-3.4%)	0.000s (+Infinity% 🔺)	2.112s (-3.9%)	0.483s	29	1.00x
🐘 Postgres	Nitro	1.778s (-0.7%)	2.102s (-1.8%)	0.000s (-100.0% 🟢)	2.113s (-2.8%)	0.335s	29	1.09x
💻 Local	Nitro	3.472s (+2.5%)	4.102s (+1.7%)	0.000s (-25.0% 🟢)	4.104s (+1.7%)	0.632s	15	2.13x
💻 Local	Express	3.573s (+3.1%)	4.099s (+1.6%)	0.001s (-16.7% 🟢)	4.101s (+1.6%)	0.528s	15	2.19x

Summary

Fastest Framework by World

Winner determined by most benchmark wins

World	🥇 Fastest Framework	Wins
💻 Local	Nitro	14/21
🐘 Postgres	Express	21/21

Fastest World by Framework

Winner determined by most benchmark wins

Framework	🥇 Fastest World	Wins
Express	🐘 Postgres	20/21
Nitro	🐘 Postgres	18/21

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
• 🌐 Turso: Community world (local development)
• 🌐 MongoDB: Community world (local development)
• 🌐 Redis: Community world (local development)
• 🌐 Jazz: Community world (local development)

---

📋 View full workflow run

[github-actions]

🧪 E2E Test Results

✅ All tests passed

Summary

	Passed	Failed	Skipped	Total
✅ ▲ Vercel Production	989	0	67	1056
✅ 💻 Local Development	1066	0	86	1152
✅ 📦 Local Production	1066	0	86	1152
✅ 🐘 Local Postgres	1066	0	86	1152
✅ 🪟 Windows	96	0	0	96
✅ 📋 Other	270	0	18	288
Total	4553	0	343	4896

Details by Category

✅ ▲ Vercel Production

App	Passed	Failed	Skipped
✅ astro	89	0	7
✅ example	89	0	7
✅ express	89	0	7
✅ fastify	89	0	7
✅ hono	89	0	7
✅ nextjs-turbopack	94	0	2
✅ nextjs-webpack	94	0	2
✅ nitro	89	0	7
✅ nuxt	89	0	7
✅ sveltekit	89	0	7
✅ vite	89	0	7

✅ 💻 Local Development

App	Passed	Failed	Skipped
✅ astro-stable	90	0	6
✅ express-stable	90	0	6
✅ fastify-stable	90	0	6
✅ hono-stable	90	0	6
✅ nextjs-turbopack-canary	77	0	19
✅ nextjs-turbopack-stable	96	0	0
✅ nextjs-webpack-canary	77	0	19
✅ nextjs-webpack-stable	96	0	0
✅ nitro-stable	90	0	6
✅ nuxt-stable	90	0	6
✅ sveltekit-stable	90	0	6
✅ vite-stable	90	0	6

✅ 📦 Local Production

App	Passed	Failed	Skipped
✅ astro-stable	90	0	6
✅ express-stable	90	0	6
✅ fastify-stable	90	0	6
✅ hono-stable	90	0	6
✅ nextjs-turbopack-canary	77	0	19
✅ nextjs-turbopack-stable	96	0	0
✅ nextjs-webpack-canary	77	0	19
✅ nextjs-webpack-stable	96	0	0
✅ nitro-stable	90	0	6
✅ nuxt-stable	90	0	6
✅ sveltekit-stable	90	0	6
✅ vite-stable	90	0	6

✅ 🐘 Local Postgres

App	Passed	Failed	Skipped
✅ astro-stable	90	0	6
✅ express-stable	90	0	6
✅ fastify-stable	90	0	6
✅ hono-stable	90	0	6
✅ nextjs-turbopack-canary	77	0	19
✅ nextjs-turbopack-stable	96	0	0
✅ nextjs-webpack-canary	77	0	19
✅ nextjs-webpack-stable	96	0	0
✅ nitro-stable	90	0	6
✅ nuxt-stable	90	0	6
✅ sveltekit-stable	90	0	6
✅ vite-stable	90	0	6

✅ 🪟 Windows

App	Passed	Failed	Skipped
✅ nextjs-turbopack	96	0	0

✅ 📋 Other

App	Passed	Failed	Skipped
✅ e2e-local-dev-nest-stable	90	0	6
✅ e2e-local-postgres-nest-stable	90	0	6
✅ e2e-local-prod-nest-stable	90	0	6

---

📋 View full workflow run

[Copilot]

Pull request overview

This PR hardens @workflow/world-local’s filesystem-backed storage against path traversal by validating request-supplied identifiers before they’re used in file paths, and adds regression tests to cover common traversal payloads.

Changes:

• Introduces assertSafeEntityId (and UnsafeEntityIdError) and applies it across filesystem path composition helpers.
• Adds ID validation at storage entry points (runs/steps/events/hooks) and streamer operations that use IDs in filenames.
• Expands unit + integration coverage to ensure traversal payloads are rejected; adds a changeset for the patch release.

Reviewed changes

Copilot reviewed 9 out of 9 changed files in this pull request and generated 5 comments.

Show a summary per file

File	Description
packages/world-local/src/fs.ts	Adds centralized ID validation + applies it in taggedPath, readJSONWithFallback, and paginatedFileSystemQuery.
packages/world-local/src/streamer.ts	Validates runId and streamName before using them as filename prefixes / keys.
packages/world-local/src/storage/runs-storage.ts	Validates runId before reading run JSON from disk.
packages/world-local/src/storage/steps-storage.ts	Validates runId/stepId before reading steps and before listing by run prefix.
packages/world-local/src/storage/events-storage.ts	Validates runId/eventId and request correlationId before composing composite keys and paths.
packages/world-local/src/storage/hooks-storage.ts	Validates hookId before reading hook JSON from disk.
packages/world-local/src/fs.test.ts	Adds focused tests for assertSafeEntityId and for validation in taggedPath/readJSONWithFallback.
packages/world-local/src/storage.test.ts	Adds regression tests ensuring traversal payloads are rejected across storage APIs.
.changeset/world-local-path-traversal.md	Declares a patch release for the security fix.

---

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[pranaygp]

Solid, well-scoped fix. Validation is applied at every entry point I could trace, tests cover the exact payloads from the Latacora report, and all 328 @workflow/world-local tests pass locally. A few non-blocking suggestions inline — mostly around defense-in-depth and error-type consistency. Copilot already flagged the docstring inaccuracies so I won't duplicate those.

One additional note not worth a line comment: legacy.ts's handleLegacyEvent uses runId in path.join directly (lines 47 and 73 — unchanged by this PR). It's safe today because the function is only called from events.create after assertSafeEntityId('runId', runId) has already run, but the function is exported and nothing in its signature documents that invariant. A one-line assertSafeEntityId('runId', runId) at the top of handleLegacyEvent would make the guarantee local to the file.

[pranaygp]

Two follow-ups not already covered in prior review rounds.

[TooTallNate]

Thanks for the review. Pushed b33b922 addressing every comment:

• UnsafeEntityIdError now extends WorkflowWorldError (with name + static is()) so it flows through the platform's normal error mapping instead of surfacing as a generic 500.
• Added resolveWithinBase(basedir, ...segments) as the belt-and-suspenders containment check, and routed every path.join-with-user-input through it (taggedPath, readJSONWithFallback, all four .locks/** sites in events-storage.ts, and the two sites in legacy.ts).
• handleLegacyEvent now re-asserts runId locally so the invariant is documented at the call site (per your top-level note) and both its path.join sites use resolveWithinBase.
• Error message values are truncated (48 chars + ellipsis) via truncateForError to limit attacker feedback.
• Removed the unused assertSafeEntityIds helper and the unreachable typeof branch.
• Fixed the docstring / example / filePrefix comment inaccuracies Copilot flagged.

Tests: 335 passing in @workflow/world-local (328 → 335, +7 for resolveWithinBase and the WorkflowWorldError hierarchy), 591 passing in @workflow/core.

[TooTallNate]

Summary

• Request-supplied identifiers (runId, eventId, stepId, hookId, correlationId, stream names, and tags) flowed straight into path.join() inside @workflow/world-local, so a client could send a payload like {"runId":"../../../package"} to /.well-known/workflow/v1/flow and read or write files outside the workflow data directory.
• Added a centralized assertSafeEntityId helper in packages/world-local/src/fs.ts that rejects IDs which are empty, start with ., or contain /, \, or NUL bytes. This is permissive enough to accept every existing valid ID shape (ULIDs, composite keys like wrun_X-step_Y, base64url stream namespaces, tags like vitest-0) while blocking real traversal vectors.
• Applied the check at each storage-layer entry point that composes IDs into filesystem paths: fs.taggedPath / readJSONWithFallback / paginatedFileSystemQuery, the runs / steps / events / hooks storage methods, and the streamer.

Test plan

• pnpm --filter @workflow/world-local test — 266 → 328 passing (62 new unit + integration tests covering the exact payloads from the report: ../../../package, ../runs/wrun_…, backslash variants, NUL bytes, .locks, etc.)
• pnpm --filter @workflow/core test — 591 passing

[changeset-bot]

🦋 Changeset detected

Latest commit: 8d3898a

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

This PR includes changesets to release 19 packages

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

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

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

[vercel]

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Project	Deployment	Actions	Updated (UTC)
example-nextjs-workflow-turbopack	Ready	Preview, Comment	Apr 30, 2026 8:43am
example-nextjs-workflow-webpack	Ready	Preview, Comment	Apr 30, 2026 8:43am
example-workflow	Ready	Preview, Comment	Apr 30, 2026 8:43am
workbench-astro-workflow	Ready	Preview, Comment	Apr 30, 2026 8:43am
workbench-express-workflow	Ready	Preview, Comment	Apr 30, 2026 8:43am
workbench-fastify-workflow	Ready	Preview, Comment	Apr 30, 2026 8:43am
workbench-hono-workflow	Ready	Preview, Comment	Apr 30, 2026 8:43am
workbench-nitro-workflow	Ready	Preview, Comment	Apr 30, 2026 8:43am
workbench-nuxt-workflow	Ready	Preview, Comment	Apr 30, 2026 8:43am
workbench-sveltekit-workflow	Ready	Preview, Comment	Apr 30, 2026 8:43am
workbench-vite-workflow	Ready	Preview, Comment	Apr 30, 2026 8:43am
workflow-docs	Ready	Preview, Comment, Open in v0	Apr 30, 2026 8:43am
workflow-swc-playground	Ready	Preview, Comment	Apr 30, 2026 8:43am
workflow-web	Ready	Preview, Comment	Apr 30, 2026 8:43am

[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	🥇 Nitro	0.044s (+2.1%)	1.005s (~)	0.961s	10	1.00x
💻 Local	Express	0.044s (~)	1.005s (~)	0.961s	10	1.00x
🐘 Postgres	Express	0.049s (-15.0% 🟢)	1.009s (~)	0.960s	10	1.12x
🐘 Postgres	Nitro	0.057s (-40.5% 🟢)	1.010s (-3.2%)	0.953s	10	1.29x

workflow with 1 step

💻 Local Development

World	Framework	Workflow Time	Wall Time	Overhead	Samples	vs Fastest
🐘 Postgres	🥇 Express	1.120s (-2.3%)	2.009s (~)	0.889s	10	1.00x
💻 Local	Express	1.126s (~)	2.005s (~)	0.880s	10	1.01x
💻 Local	Nitro	1.129s (~)	2.006s (~)	0.876s	10	1.01x
🐘 Postgres	Nitro	1.135s (~)	2.009s (~)	0.874s	10	1.01x

workflow with 10 sequential steps

💻 Local Development

World	Framework	Workflow Time	Wall Time	Overhead	Samples	vs Fastest
🐘 Postgres	🥇 Express	10.691s (-2.5%)	11.018s (~)	0.327s	3	1.00x
🐘 Postgres	Nitro	10.886s (~)	11.018s (~)	0.132s	3	1.02x
💻 Local	Express	10.937s (~)	11.023s (~)	0.086s	3	1.02x
💻 Local	Nitro	10.947s (~)	11.023s (~)	0.076s	3	1.02x

workflow with 25 sequential steps

💻 Local Development

World	Framework	Workflow Time	Wall Time	Overhead	Samples	vs Fastest
🐘 Postgres	🥇 Express	13.971s (-4.2%)	14.021s (-6.7% 🟢)	0.050s	5	1.00x
🐘 Postgres	Nitro	14.494s (-0.7%)	15.019s (~)	0.525s	4	1.04x
💻 Local	Nitro	14.982s (-0.5%)	15.280s (-4.7%)	0.298s	4	1.07x
💻 Local	Express	14.995s (~)	15.029s (~)	0.034s	4	1.07x

workflow with 50 sequential steps

💻 Local Development

World	Framework	Workflow Time	Wall Time	Overhead	Samples	vs Fastest
🐘 Postgres	🥇 Express	12.932s (-7.7% 🟢)	13.021s (-10.8% 🟢)	0.089s	7	1.00x
🐘 Postgres	Nitro	13.814s (-1.1%)	14.020s (-2.0%)	0.206s	7	1.07x
💻 Local	Nitro	16.416s (-2.2%)	17.031s (~)	0.614s	6	1.27x
💻 Local	Express	16.689s (+0.5%)	17.030s (~)	0.341s	6	1.29x

Promise.all with 10 concurrent steps

💻 Local Development

World	Framework	Workflow Time	Wall Time	Overhead	Samples	vs Fastest
🐘 Postgres	🥇 Express	1.196s (-5.1% 🟢)	2.009s (~)	0.812s	15	1.00x
🐘 Postgres	Nitro	1.253s (-1.7%)	2.009s (~)	0.756s	15	1.05x
💻 Local	Nitro	1.504s (-7.8% 🟢)	2.006s (-3.3%)	0.502s	15	1.26x
💻 Local	Express	1.512s (+1.6%)	2.006s (~)	0.494s	15	1.26x

Promise.all with 25 concurrent steps

💻 Local Development

World	Framework	Workflow Time	Wall Time	Overhead	Samples	vs Fastest
🐘 Postgres	🥇 Express	2.278s (-3.5%)	3.009s (~)	0.731s	10	1.00x
🐘 Postgres	Nitro	2.338s (-0.6%)	3.010s (~)	0.673s	10	1.03x
💻 Local	Nitro	2.828s (-10.0% 🟢)	3.008s (-22.6% 🟢)	0.180s	10	1.24x
💻 Local	Express	2.958s (~)	3.208s (-7.1% 🟢)	0.250s	10	1.30x

Promise.all with 50 concurrent steps

💻 Local Development

World	Framework	Workflow Time	Wall Time	Overhead	Samples	vs Fastest
🐘 Postgres	🥇 Express	3.371s (-3.3%)	4.009s (~)	0.638s	8	1.00x
🐘 Postgres	Nitro	3.455s (-0.7%)	4.010s (~)	0.554s	8	1.03x
💻 Local	Nitro	7.405s (-11.3% 🟢)	8.020s (-11.1% 🟢)	0.614s	4	2.20x
💻 Local	Express	8.209s (-1.6%)	9.022s (~)	0.814s	4	2.44x

Promise.race with 10 concurrent steps

💻 Local Development

World	Framework	Workflow Time	Wall Time	Overhead	Samples	vs Fastest
🐘 Postgres	🥇 Express	1.199s (-4.6%)	2.007s (~)	0.808s	15	1.00x
🐘 Postgres	Nitro	1.260s (~)	2.008s (~)	0.749s	15	1.05x
💻 Local	Express	1.516s (-19.9% 🟢)	2.006s (-15.2% 🟢)	0.489s	15	1.26x
💻 Local	Nitro	1.585s (-15.1% 🟢)	2.006s (-14.3% 🟢)	0.421s	15	1.32x

Promise.race with 25 concurrent steps

💻 Local Development

World	Framework	Workflow Time	Wall Time	Overhead	Samples	vs Fastest
🐘 Postgres	🥇 Express	2.269s (-3.1%)	3.009s (~)	0.740s	10	1.00x
🐘 Postgres	Nitro	2.315s (-1.0%)	3.009s (~)	0.694s	10	1.02x
💻 Local	Nitro	2.903s (-5.3% 🟢)	3.454s (-11.1% 🟢)	0.550s	9	1.28x
💻 Local	Express	3.170s (+1.2%)	4.010s (+6.6% 🔺)	0.840s	8	1.40x

Promise.race with 50 concurrent steps

💻 Local Development

World	Framework	Workflow Time	Wall Time	Overhead	Samples	vs Fastest
🐘 Postgres	🥇 Express	3.388s (-3.2%)	4.008s (~)	0.620s	8	1.00x
🐘 Postgres	Nitro	3.476s (~)	4.009s (~)	0.533s	8	1.03x
💻 Local	Nitro	8.071s (-11.7% 🟢)	9.021s (-10.0% 🟢)	0.950s	4	2.38x
💻 Local	Express	8.942s (+1.6%)	9.276s (~)	0.335s	4	2.64x

workflow with 10 sequential data payload steps (10KB)

💻 Local Development

World	Framework	Workflow Time	Wall Time	Overhead	Samples	vs Fastest
🐘 Postgres	🥇 Express	0.587s (-30.0% 🟢)	1.006s (-1.7%)	0.419s	60	1.00x
🐘 Postgres	Nitro	0.789s (-3.8%)	1.006s (~)	0.216s	60	1.34x
💻 Local	Express	0.987s (~)	1.158s (+7.7% 🔺)	0.171s	52	1.68x
💻 Local	Nitro	1.011s (+3.1%)	1.627s (+48.7% 🔺)	0.616s	37	1.72x

workflow with 25 sequential data payload steps (10KB)

💻 Local Development

World	Framework	Workflow Time	Wall Time	Overhead	Samples	vs Fastest
🐘 Postgres	🥇 Express	1.406s (-28.9% 🟢)	2.007s (-11.1% 🟢)	0.601s	45	1.00x
🐘 Postgres	Nitro	1.886s (-2.2%)	2.030s (-3.4%)	0.144s	45	1.34x
💻 Local	Express	3.040s (+0.8%)	3.609s (+0.7%)	0.569s	25	2.16x
💻 Local	Nitro	3.048s (~)	3.729s (-0.8%)	0.681s	25	2.17x

workflow with 50 sequential data payload steps (10KB)

💻 Local Development

World	Framework	Workflow Time	Wall Time	Overhead	Samples	vs Fastest
🐘 Postgres	🥇 Express	2.926s (-26.7% 🟢)	3.137s (-28.2% 🟢)	0.210s	39	1.00x
🐘 Postgres	Nitro	3.860s (-5.9% 🟢)	4.077s (-11.4% 🟢)	0.218s	30	1.32x
💻 Local	Nitro	8.969s (-3.5%)	9.479s (-5.4% 🟢)	0.510s	13	3.06x
💻 Local	Express	9.232s (~)	9.942s (-0.8%)	0.710s	13	3.15x

workflow with 10 concurrent data payload steps (10KB)

💻 Local Development

World	Framework	Workflow Time	Wall Time	Overhead	Samples	vs Fastest
🐘 Postgres	🥇 Express	0.226s (-20.0% 🟢)	1.007s (~)	0.781s	60	1.00x
🐘 Postgres	Nitro	0.272s (-4.1%)	1.007s (~)	0.735s	60	1.20x
💻 Local	Nitro	0.551s (-8.9% 🟢)	1.004s (-1.7%)	0.454s	60	2.44x
💻 Local	Express	0.578s (+3.2%)	1.004s (~)	0.426s	60	2.56x

workflow with 25 concurrent data payload steps (10KB)

💻 Local Development

World	Framework	Workflow Time	Wall Time	Overhead	Samples	vs Fastest
🐘 Postgres	🥇 Express	0.354s (-30.5% 🟢)	1.006s (~)	0.651s	90	1.00x
🐘 Postgres	Nitro	0.484s (-2.5%)	1.007s (~)	0.523s	90	1.37x
💻 Local	Nitro	2.402s (-5.4% 🟢)	3.009s (~)	0.607s	30	6.78x
💻 Local	Express	2.564s (+2.0%)	3.009s (~)	0.445s	30	7.24x

workflow with 50 concurrent data payload steps (10KB)

💻 Local Development

World	Framework	Workflow Time	Wall Time	Overhead	Samples	vs Fastest
🐘 Postgres	🥇 Express	0.564s (-31.2% 🟢)	1.006s (-1.1%)	0.443s	120	1.00x
🐘 Postgres	Nitro	0.769s (-2.6%)	1.007s (~)	0.238s	120	1.37x
💻 Local	Nitro	10.339s (-7.6% 🟢)	11.028s (-5.5% 🟢)	0.689s	11	18.34x
💻 Local	Express	11.094s (-0.9%)	11.756s (-1.5%)	0.662s	11	19.68x

Stream Benchmarks(includes TTFB metrics)

workflow with stream

💻 Local Development

World	Framework	Workflow Time	TTFB	Slurp	Wall Time	Overhead	Samples	vs Fastest
🐘 Postgres	🥇 Express	0.153s (-25.5% 🟢)	1.000s (~)	0.001s (-31.3% 🟢)	1.009s (~)	0.856s	10	1.00x
💻 Local	Express	0.201s (+0.7%)	1.004s (~)	0.012s (+2.5%)	1.019s (~)	0.818s	10	1.31x
💻 Local	Nitro	0.205s (-3.9%)	1.004s (~)	0.010s (-20.0% 🟢)	1.016s (~)	0.810s	10	1.34x
🐘 Postgres	Nitro	0.208s (+1.6%)	0.995s (~)	0.001s (-6.7% 🟢)	1.009s (~)	0.801s	10	1.36x

stream pipeline with 5 transform steps (1MB)

💻 Local Development

World	Framework	Workflow Time	TTFB	Slurp	Wall Time	Overhead	Samples	vs Fastest
🐘 Postgres	🥇 Express	0.496s (-21.2% 🟢)	1.006s (~)	0.003s (-9.7% 🟢)	1.020s (~)	0.524s	59	1.00x
🐘 Postgres	Nitro	0.597s (-4.4%)	1.007s (~)	0.004s (-5.7% 🟢)	1.021s (~)	0.424s	59	1.20x
💻 Local	Express	0.752s (-0.6%)	1.012s (-1.6%)	0.010s (+1.5%)	1.024s (-1.6%)	0.271s	59	1.52x
💻 Local	Nitro	0.857s (+2.2%)	1.011s (~)	0.009s (-1.4%)	1.115s (~)	0.258s	54	1.73x

10 parallel streams (1MB each)

💻 Local Development

World	Framework	Workflow Time	TTFB	Slurp	Wall Time	Overhead	Samples	vs Fastest
🐘 Postgres	🥇 Express	0.903s (-6.0% 🟢)	1.109s (-13.2% 🟢)	0.000s (+25.5% 🔺)	1.118s (-14.4% 🟢)	0.215s	55	1.00x
🐘 Postgres	Nitro	0.946s (-2.3%)	1.148s (-7.9% 🟢)	0.000s (-53.8% 🟢)	1.161s (-7.7% 🟢)	0.215s	52	1.05x
💻 Local	Nitro	1.208s (-1.2%)	2.020s (~)	0.000s (+233.3% 🔺)	2.022s (~)	0.814s	30	1.34x
💻 Local	Express	1.245s (+1.6%)	2.023s (~)	0.000s (-10.0% 🟢)	2.024s (~)	0.780s	30	1.38x

fan-out fan-in 10 streams (1MB each)

💻 Local Development

World	Framework	Workflow Time	TTFB	Slurp	Wall Time	Overhead	Samples	vs Fastest
🐘 Postgres	🥇 Express	1.629s (-8.1% 🟢)	2.103s (-3.4%)	0.000s (+Infinity% 🔺)	2.112s (-3.9%)	0.483s	29	1.00x
🐘 Postgres	Nitro	1.778s (-0.7%)	2.102s (-1.8%)	0.000s (-100.0% 🟢)	2.113s (-2.8%)	0.335s	29	1.09x
💻 Local	Nitro	3.472s (+2.5%)	4.102s (+1.7%)	0.000s (-25.0% 🟢)	4.104s (+1.7%)	0.632s	15	2.13x
💻 Local	Express	3.573s (+3.1%)	4.099s (+1.6%)	0.001s (-16.7% 🟢)	4.101s (+1.6%)	0.528s	15	2.19x

Summary

Fastest Framework by World

Winner determined by most benchmark wins

World	🥇 Fastest Framework	Wins
💻 Local	Nitro	14/21
🐘 Postgres	Express	21/21

Fastest World by Framework

Winner determined by most benchmark wins

Framework	🥇 Fastest World	Wins
Express	🐘 Postgres	20/21
Nitro	🐘 Postgres	18/21

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
• 🌐 Turso: Community world (local development)
• 🌐 MongoDB: Community world (local development)
• 🌐 Redis: Community world (local development)
• 🌐 Jazz: Community world (local development)

---

📋 View full workflow run

[github-actions]

🧪 E2E Test Results

✅ All tests passed

Summary

	Passed	Failed	Skipped	Total
✅ ▲ Vercel Production	989	0	67	1056
✅ 💻 Local Development	1066	0	86	1152
✅ 📦 Local Production	1066	0	86	1152
✅ 🐘 Local Postgres	1066	0	86	1152
✅ 🪟 Windows	96	0	0	96
✅ 📋 Other	270	0	18	288
Total	4553	0	343	4896

Details by Category

✅ ▲ Vercel Production

App	Passed	Failed	Skipped
✅ astro	89	0	7
✅ example	89	0	7
✅ express	89	0	7
✅ fastify	89	0	7
✅ hono	89	0	7
✅ nextjs-turbopack	94	0	2
✅ nextjs-webpack	94	0	2
✅ nitro	89	0	7
✅ nuxt	89	0	7
✅ sveltekit	89	0	7
✅ vite	89	0	7

✅ 💻 Local Development

App	Passed	Failed	Skipped
✅ astro-stable	90	0	6
✅ express-stable	90	0	6
✅ fastify-stable	90	0	6
✅ hono-stable	90	0	6
✅ nextjs-turbopack-canary	77	0	19
✅ nextjs-turbopack-stable	96	0	0
✅ nextjs-webpack-canary	77	0	19
✅ nextjs-webpack-stable	96	0	0
✅ nitro-stable	90	0	6
✅ nuxt-stable	90	0	6
✅ sveltekit-stable	90	0	6
✅ vite-stable	90	0	6

✅ 📦 Local Production

App	Passed	Failed	Skipped
✅ astro-stable	90	0	6
✅ express-stable	90	0	6
✅ fastify-stable	90	0	6
✅ hono-stable	90	0	6
✅ nextjs-turbopack-canary	77	0	19
✅ nextjs-turbopack-stable	96	0	0
✅ nextjs-webpack-canary	77	0	19
✅ nextjs-webpack-stable	96	0	0
✅ nitro-stable	90	0	6
✅ nuxt-stable	90	0	6
✅ sveltekit-stable	90	0	6
✅ vite-stable	90	0	6

✅ 🐘 Local Postgres

App	Passed	Failed	Skipped
✅ astro-stable	90	0	6
✅ express-stable	90	0	6
✅ fastify-stable	90	0	6
✅ hono-stable	90	0	6
✅ nextjs-turbopack-canary	77	0	19
✅ nextjs-turbopack-stable	96	0	0
✅ nextjs-webpack-canary	77	0	19
✅ nextjs-webpack-stable	96	0	0
✅ nitro-stable	90	0	6
✅ nuxt-stable	90	0	6
✅ sveltekit-stable	90	0	6
✅ vite-stable	90	0	6

✅ 🪟 Windows

App	Passed	Failed	Skipped
✅ nextjs-turbopack	96	0	0

✅ 📋 Other

App	Passed	Failed	Skipped
✅ e2e-local-dev-nest-stable	90	0	6
✅ e2e-local-postgres-nest-stable	90	0	6
✅ e2e-local-prod-nest-stable	90	0	6

---

📋 View full workflow run

[Copilot]

Pull request overview

This PR hardens @workflow/world-local’s filesystem-backed storage against path traversal by validating request-supplied identifiers before they’re used in file paths, and adds regression tests to cover common traversal payloads.

Changes:

• Introduces assertSafeEntityId (and UnsafeEntityIdError) and applies it across filesystem path composition helpers.
• Adds ID validation at storage entry points (runs/steps/events/hooks) and streamer operations that use IDs in filenames.
• Expands unit + integration coverage to ensure traversal payloads are rejected; adds a changeset for the patch release.

Reviewed changes

Copilot reviewed 9 out of 9 changed files in this pull request and generated 5 comments.

Show a summary per file

File	Description
packages/world-local/src/fs.ts	Adds centralized ID validation + applies it in taggedPath, readJSONWithFallback, and paginatedFileSystemQuery.
packages/world-local/src/streamer.ts	Validates runId and streamName before using them as filename prefixes / keys.
packages/world-local/src/storage/runs-storage.ts	Validates runId before reading run JSON from disk.
packages/world-local/src/storage/steps-storage.ts	Validates runId/stepId before reading steps and before listing by run prefix.
packages/world-local/src/storage/events-storage.ts	Validates runId/eventId and request correlationId before composing composite keys and paths.
packages/world-local/src/storage/hooks-storage.ts	Validates hookId before reading hook JSON from disk.
packages/world-local/src/fs.test.ts	Adds focused tests for assertSafeEntityId and for validation in taggedPath/readJSONWithFallback.
packages/world-local/src/storage.test.ts	Adds regression tests ensuring traversal payloads are rejected across storage APIs.
.changeset/world-local-path-traversal.md	Declares a patch release for the security fix.

---

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[pranaygp]

Solid, well-scoped fix. Validation is applied at every entry point I could trace, tests cover the exact payloads from the Latacora report, and all 328 @workflow/world-local tests pass locally. A few non-blocking suggestions inline — mostly around defense-in-depth and error-type consistency. Copilot already flagged the docstring inaccuracies so I won't duplicate those.

One additional note not worth a line comment: legacy.ts's handleLegacyEvent uses runId in path.join directly (lines 47 and 73 — unchanged by this PR). It's safe today because the function is only called from events.create after assertSafeEntityId('runId', runId) has already run, but the function is exported and nothing in its signature documents that invariant. A one-line assertSafeEntityId('runId', runId) at the top of handleLegacyEvent would make the guarantee local to the file.

[pranaygp]

Two follow-ups not already covered in prior review rounds.

[TooTallNate]

Thanks for the review. Pushed b33b922 addressing every comment:

• UnsafeEntityIdError now extends WorkflowWorldError (with name + static is()) so it flows through the platform's normal error mapping instead of surfacing as a generic 500.
• Added resolveWithinBase(basedir, ...segments) as the belt-and-suspenders containment check, and routed every path.join-with-user-input through it (taggedPath, readJSONWithFallback, all four .locks/** sites in events-storage.ts, and the two sites in legacy.ts).
• handleLegacyEvent now re-asserts runId locally so the invariant is documented at the call site (per your top-level note) and both its path.join sites use resolveWithinBase.
• Error message values are truncated (48 chars + ellipsis) via truncateForError to limit attacker feedback.
• Removed the unused assertSafeEntityIds helper and the unreachable typeof branch.
• Fixed the docstring / example / filePrefix comment inaccuracies Copilot flagged.

Tests: 335 passing in @workflow/world-local (328 → 335, +7 for resolveWithinBase and the WorkflowWorldError hierarchy), 591 passing in @workflow/core.

[TooTallNate]

Summary

• Request-supplied identifiers (runId, eventId, stepId, hookId, correlationId, stream names, and tags) flowed straight into path.join() inside @workflow/world-local, so a client could send a payload like {"runId":"../../../package"} to /.well-known/workflow/v1/flow and read or write files outside the workflow data directory.
• Added a centralized assertSafeEntityId helper in packages/world-local/src/fs.ts that rejects IDs which are empty, start with ., or contain /, \, or NUL bytes. This is permissive enough to accept every existing valid ID shape (ULIDs, composite keys like wrun_X-step_Y, base64url stream namespaces, tags like vitest-0) while blocking real traversal vectors.
• Applied the check at each storage-layer entry point that composes IDs into filesystem paths: fs.taggedPath / readJSONWithFallback / paginatedFileSystemQuery, the runs / steps / events / hooks storage methods, and the streamer.

Test plan

• pnpm --filter @workflow/world-local test — 266 → 328 passing (62 new unit + integration tests covering the exact payloads from the report: ../../../package, ../runs/wrun_…, backslash variants, NUL bytes, .locks, etc.)
• pnpm --filter @workflow/core test — 591 passing

[changeset-bot]

🦋 Changeset detected

Latest commit: 8d3898a

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

This PR includes changesets to release 19 packages

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

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

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

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Project	Deployment	Actions	Updated (UTC)
example-nextjs-workflow-turbopack	Ready	Preview, Comment	Apr 30, 2026 8:43am
example-nextjs-workflow-webpack	Ready	Preview, Comment	Apr 30, 2026 8:43am
example-workflow	Ready	Preview, Comment	Apr 30, 2026 8:43am
workbench-astro-workflow	Ready	Preview, Comment	Apr 30, 2026 8:43am
workbench-express-workflow	Ready	Preview, Comment	Apr 30, 2026 8:43am
workbench-fastify-workflow	Ready	Preview, Comment	Apr 30, 2026 8:43am
workbench-hono-workflow	Ready	Preview, Comment	Apr 30, 2026 8:43am
workbench-nitro-workflow	Ready	Preview, Comment	Apr 30, 2026 8:43am
workbench-nuxt-workflow	Ready	Preview, Comment	Apr 30, 2026 8:43am
workbench-sveltekit-workflow	Ready	Preview, Comment	Apr 30, 2026 8:43am
workbench-vite-workflow	Ready	Preview, Comment	Apr 30, 2026 8:43am
workflow-docs	Ready	Preview, Comment, Open in v0	Apr 30, 2026 8:43am
workflow-swc-playground	Ready	Preview, Comment	Apr 30, 2026 8:43am
workflow-web	Ready	Preview, Comment	Apr 30, 2026 8:43am

[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	🥇 Nitro	0.044s (+2.1%)	1.005s (~)	0.961s	10	1.00x
💻 Local	Express	0.044s (~)	1.005s (~)	0.961s	10	1.00x
🐘 Postgres	Express	0.049s (-15.0% 🟢)	1.009s (~)	0.960s	10	1.12x
🐘 Postgres	Nitro	0.057s (-40.5% 🟢)	1.010s (-3.2%)	0.953s	10	1.29x

workflow with 1 step

💻 Local Development

World	Framework	Workflow Time	Wall Time	Overhead	Samples	vs Fastest
🐘 Postgres	🥇 Express	1.120s (-2.3%)	2.009s (~)	0.889s	10	1.00x
💻 Local	Express	1.126s (~)	2.005s (~)	0.880s	10	1.01x
💻 Local	Nitro	1.129s (~)	2.006s (~)	0.876s	10	1.01x
🐘 Postgres	Nitro	1.135s (~)	2.009s (~)	0.874s	10	1.01x

workflow with 10 sequential steps

💻 Local Development

World	Framework	Workflow Time	Wall Time	Overhead	Samples	vs Fastest
🐘 Postgres	🥇 Express	10.691s (-2.5%)	11.018s (~)	0.327s	3	1.00x
🐘 Postgres	Nitro	10.886s (~)	11.018s (~)	0.132s	3	1.02x
💻 Local	Express	10.937s (~)	11.023s (~)	0.086s	3	1.02x
💻 Local	Nitro	10.947s (~)	11.023s (~)	0.076s	3	1.02x

workflow with 25 sequential steps

💻 Local Development

World	Framework	Workflow Time	Wall Time	Overhead	Samples	vs Fastest
🐘 Postgres	🥇 Express	13.971s (-4.2%)	14.021s (-6.7% 🟢)	0.050s	5	1.00x
🐘 Postgres	Nitro	14.494s (-0.7%)	15.019s (~)	0.525s	4	1.04x
💻 Local	Nitro	14.982s (-0.5%)	15.280s (-4.7%)	0.298s	4	1.07x
💻 Local	Express	14.995s (~)	15.029s (~)	0.034s	4	1.07x

workflow with 50 sequential steps

💻 Local Development

World	Framework	Workflow Time	Wall Time	Overhead	Samples	vs Fastest
🐘 Postgres	🥇 Express	12.932s (-7.7% 🟢)	13.021s (-10.8% 🟢)	0.089s	7	1.00x
🐘 Postgres	Nitro	13.814s (-1.1%)	14.020s (-2.0%)	0.206s	7	1.07x
💻 Local	Nitro	16.416s (-2.2%)	17.031s (~)	0.614s	6	1.27x
💻 Local	Express	16.689s (+0.5%)	17.030s (~)	0.341s	6	1.29x

Promise.all with 10 concurrent steps

💻 Local Development

World	Framework	Workflow Time	Wall Time	Overhead	Samples	vs Fastest
🐘 Postgres	🥇 Express	1.196s (-5.1% 🟢)	2.009s (~)	0.812s	15	1.00x
🐘 Postgres	Nitro	1.253s (-1.7%)	2.009s (~)	0.756s	15	1.05x
💻 Local	Nitro	1.504s (-7.8% 🟢)	2.006s (-3.3%)	0.502s	15	1.26x
💻 Local	Express	1.512s (+1.6%)	2.006s (~)	0.494s	15	1.26x

Promise.all with 25 concurrent steps

💻 Local Development

World	Framework	Workflow Time	Wall Time	Overhead	Samples	vs Fastest
🐘 Postgres	🥇 Express	2.278s (-3.5%)	3.009s (~)	0.731s	10	1.00x
🐘 Postgres	Nitro	2.338s (-0.6%)	3.010s (~)	0.673s	10	1.03x
💻 Local	Nitro	2.828s (-10.0% 🟢)	3.008s (-22.6% 🟢)	0.180s	10	1.24x
💻 Local	Express	2.958s (~)	3.208s (-7.1% 🟢)	0.250s	10	1.30x

Promise.all with 50 concurrent steps

💻 Local Development

World	Framework	Workflow Time	Wall Time	Overhead	Samples	vs Fastest
🐘 Postgres	🥇 Express	3.371s (-3.3%)	4.009s (~)	0.638s	8	1.00x
🐘 Postgres	Nitro	3.455s (-0.7%)	4.010s (~)	0.554s	8	1.03x
💻 Local	Nitro	7.405s (-11.3% 🟢)	8.020s (-11.1% 🟢)	0.614s	4	2.20x
💻 Local	Express	8.209s (-1.6%)	9.022s (~)	0.814s	4	2.44x

Promise.race with 10 concurrent steps

💻 Local Development

World	Framework	Workflow Time	Wall Time	Overhead	Samples	vs Fastest
🐘 Postgres	🥇 Express	1.199s (-4.6%)	2.007s (~)	0.808s	15	1.00x
🐘 Postgres	Nitro	1.260s (~)	2.008s (~)	0.749s	15	1.05x
💻 Local	Express	1.516s (-19.9% 🟢)	2.006s (-15.2% 🟢)	0.489s	15	1.26x
💻 Local	Nitro	1.585s (-15.1% 🟢)	2.006s (-14.3% 🟢)	0.421s	15	1.32x

Promise.race with 25 concurrent steps

💻 Local Development

World	Framework	Workflow Time	Wall Time	Overhead	Samples	vs Fastest
🐘 Postgres	🥇 Express	2.269s (-3.1%)	3.009s (~)	0.740s	10	1.00x
🐘 Postgres	Nitro	2.315s (-1.0%)	3.009s (~)	0.694s	10	1.02x
💻 Local	Nitro	2.903s (-5.3% 🟢)	3.454s (-11.1% 🟢)	0.550s	9	1.28x
💻 Local	Express	3.170s (+1.2%)	4.010s (+6.6% 🔺)	0.840s	8	1.40x

Promise.race with 50 concurrent steps

💻 Local Development

World	Framework	Workflow Time	Wall Time	Overhead	Samples	vs Fastest
🐘 Postgres	🥇 Express	3.388s (-3.2%)	4.008s (~)	0.620s	8	1.00x
🐘 Postgres	Nitro	3.476s (~)	4.009s (~)	0.533s	8	1.03x
💻 Local	Nitro	8.071s (-11.7% 🟢)	9.021s (-10.0% 🟢)	0.950s	4	2.38x
💻 Local	Express	8.942s (+1.6%)	9.276s (~)	0.335s	4	2.64x

workflow with 10 sequential data payload steps (10KB)

💻 Local Development

World	Framework	Workflow Time	Wall Time	Overhead	Samples	vs Fastest
🐘 Postgres	🥇 Express	0.587s (-30.0% 🟢)	1.006s (-1.7%)	0.419s	60	1.00x
🐘 Postgres	Nitro	0.789s (-3.8%)	1.006s (~)	0.216s	60	1.34x
💻 Local	Express	0.987s (~)	1.158s (+7.7% 🔺)	0.171s	52	1.68x
💻 Local	Nitro	1.011s (+3.1%)	1.627s (+48.7% 🔺)	0.616s	37	1.72x

workflow with 25 sequential data payload steps (10KB)

💻 Local Development

World	Framework	Workflow Time	Wall Time	Overhead	Samples	vs Fastest
🐘 Postgres	🥇 Express	1.406s (-28.9% 🟢)	2.007s (-11.1% 🟢)	0.601s	45	1.00x
🐘 Postgres	Nitro	1.886s (-2.2%)	2.030s (-3.4%)	0.144s	45	1.34x
💻 Local	Express	3.040s (+0.8%)	3.609s (+0.7%)	0.569s	25	2.16x
💻 Local	Nitro	3.048s (~)	3.729s (-0.8%)	0.681s	25	2.17x

workflow with 50 sequential data payload steps (10KB)

💻 Local Development

World	Framework	Workflow Time	Wall Time	Overhead	Samples	vs Fastest
🐘 Postgres	🥇 Express	2.926s (-26.7% 🟢)	3.137s (-28.2% 🟢)	0.210s	39	1.00x
🐘 Postgres	Nitro	3.860s (-5.9% 🟢)	4.077s (-11.4% 🟢)	0.218s	30	1.32x
💻 Local	Nitro	8.969s (-3.5%)	9.479s (-5.4% 🟢)	0.510s	13	3.06x
💻 Local	Express	9.232s (~)	9.942s (-0.8%)	0.710s	13	3.15x

workflow with 10 concurrent data payload steps (10KB)

💻 Local Development

World	Framework	Workflow Time	Wall Time	Overhead	Samples	vs Fastest
🐘 Postgres	🥇 Express	0.226s (-20.0% 🟢)	1.007s (~)	0.781s	60	1.00x
🐘 Postgres	Nitro	0.272s (-4.1%)	1.007s (~)	0.735s	60	1.20x
💻 Local	Nitro	0.551s (-8.9% 🟢)	1.004s (-1.7%)	0.454s	60	2.44x
💻 Local	Express	0.578s (+3.2%)	1.004s (~)	0.426s	60	2.56x

workflow with 25 concurrent data payload steps (10KB)

💻 Local Development

World	Framework	Workflow Time	Wall Time	Overhead	Samples	vs Fastest
🐘 Postgres	🥇 Express	0.354s (-30.5% 🟢)	1.006s (~)	0.651s	90	1.00x
🐘 Postgres	Nitro	0.484s (-2.5%)	1.007s (~)	0.523s	90	1.37x
💻 Local	Nitro	2.402s (-5.4% 🟢)	3.009s (~)	0.607s	30	6.78x
💻 Local	Express	2.564s (+2.0%)	3.009s (~)	0.445s	30	7.24x

workflow with 50 concurrent data payload steps (10KB)

💻 Local Development

World	Framework	Workflow Time	Wall Time	Overhead	Samples	vs Fastest
🐘 Postgres	🥇 Express	0.564s (-31.2% 🟢)	1.006s (-1.1%)	0.443s	120	1.00x
🐘 Postgres	Nitro	0.769s (-2.6%)	1.007s (~)	0.238s	120	1.37x
💻 Local	Nitro	10.339s (-7.6% 🟢)	11.028s (-5.5% 🟢)	0.689s	11	18.34x
💻 Local	Express	11.094s (-0.9%)	11.756s (-1.5%)	0.662s	11	19.68x

Stream Benchmarks(includes TTFB metrics)

workflow with stream

💻 Local Development

World	Framework	Workflow Time	TTFB	Slurp	Wall Time	Overhead	Samples	vs Fastest
🐘 Postgres	🥇 Express	0.153s (-25.5% 🟢)	1.000s (~)	0.001s (-31.3% 🟢)	1.009s (~)	0.856s	10	1.00x
💻 Local	Express	0.201s (+0.7%)	1.004s (~)	0.012s (+2.5%)	1.019s (~)	0.818s	10	1.31x
💻 Local	Nitro	0.205s (-3.9%)	1.004s (~)	0.010s (-20.0% 🟢)	1.016s (~)	0.810s	10	1.34x
🐘 Postgres	Nitro	0.208s (+1.6%)	0.995s (~)	0.001s (-6.7% 🟢)	1.009s (~)	0.801s	10	1.36x

stream pipeline with 5 transform steps (1MB)

💻 Local Development

World	Framework	Workflow Time	TTFB	Slurp	Wall Time	Overhead	Samples	vs Fastest
🐘 Postgres	🥇 Express	0.496s (-21.2% 🟢)	1.006s (~)	0.003s (-9.7% 🟢)	1.020s (~)	0.524s	59	1.00x
🐘 Postgres	Nitro	0.597s (-4.4%)	1.007s (~)	0.004s (-5.7% 🟢)	1.021s (~)	0.424s	59	1.20x
💻 Local	Express	0.752s (-0.6%)	1.012s (-1.6%)	0.010s (+1.5%)	1.024s (-1.6%)	0.271s	59	1.52x
💻 Local	Nitro	0.857s (+2.2%)	1.011s (~)	0.009s (-1.4%)	1.115s (~)	0.258s	54	1.73x

10 parallel streams (1MB each)

💻 Local Development

World	Framework	Workflow Time	TTFB	Slurp	Wall Time	Overhead	Samples	vs Fastest
🐘 Postgres	🥇 Express	0.903s (-6.0% 🟢)	1.109s (-13.2% 🟢)	0.000s (+25.5% 🔺)	1.118s (-14.4% 🟢)	0.215s	55	1.00x
🐘 Postgres	Nitro	0.946s (-2.3%)	1.148s (-7.9% 🟢)	0.000s (-53.8% 🟢)	1.161s (-7.7% 🟢)	0.215s	52	1.05x
💻 Local	Nitro	1.208s (-1.2%)	2.020s (~)	0.000s (+233.3% 🔺)	2.022s (~)	0.814s	30	1.34x
💻 Local	Express	1.245s (+1.6%)	2.023s (~)	0.000s (-10.0% 🟢)	2.024s (~)	0.780s	30	1.38x

fan-out fan-in 10 streams (1MB each)

💻 Local Development

World	Framework	Workflow Time	TTFB	Slurp	Wall Time	Overhead	Samples	vs Fastest
🐘 Postgres	🥇 Express	1.629s (-8.1% 🟢)	2.103s (-3.4%)	0.000s (+Infinity% 🔺)	2.112s (-3.9%)	0.483s	29	1.00x
🐘 Postgres	Nitro	1.778s (-0.7%)	2.102s (-1.8%)	0.000s (-100.0% 🟢)	2.113s (-2.8%)	0.335s	29	1.09x
💻 Local	Nitro	3.472s (+2.5%)	4.102s (+1.7%)	0.000s (-25.0% 🟢)	4.104s (+1.7%)	0.632s	15	2.13x
💻 Local	Express	3.573s (+3.1%)	4.099s (+1.6%)	0.001s (-16.7% 🟢)	4.101s (+1.6%)	0.528s	15	2.19x

Summary

Fastest Framework by World

Winner determined by most benchmark wins

World	🥇 Fastest Framework	Wins
💻 Local	Nitro	14/21
🐘 Postgres	Express	21/21

Fastest World by Framework

Winner determined by most benchmark wins

Framework	🥇 Fastest World	Wins
Express	🐘 Postgres	20/21
Nitro	🐘 Postgres	18/21

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
• 🌐 Turso: Community world (local development)
• 🌐 MongoDB: Community world (local development)
• 🌐 Redis: Community world (local development)
• 🌐 Jazz: Community world (local development)

---

📋 View full workflow run

[github-actions]

🧪 E2E Test Results

✅ All tests passed

Summary

	Passed	Failed	Skipped	Total
✅ ▲ Vercel Production	989	0	67	1056
✅ 💻 Local Development	1066	0	86	1152
✅ 📦 Local Production	1066	0	86	1152
✅ 🐘 Local Postgres	1066	0	86	1152
✅ 🪟 Windows	96	0	0	96
✅ 📋 Other	270	0	18	288
Total	4553	0	343	4896

Details by Category

✅ ▲ Vercel Production

App	Passed	Failed	Skipped
✅ astro	89	0	7
✅ example	89	0	7
✅ express	89	0	7
✅ fastify	89	0	7
✅ hono	89	0	7
✅ nextjs-turbopack	94	0	2
✅ nextjs-webpack	94	0	2
✅ nitro	89	0	7
✅ nuxt	89	0	7
✅ sveltekit	89	0	7
✅ vite	89	0	7

✅ 💻 Local Development

App	Passed	Failed	Skipped
✅ astro-stable	90	0	6
✅ express-stable	90	0	6
✅ fastify-stable	90	0	6
✅ hono-stable	90	0	6
✅ nextjs-turbopack-canary	77	0	19
✅ nextjs-turbopack-stable	96	0	0
✅ nextjs-webpack-canary	77	0	19
✅ nextjs-webpack-stable	96	0	0
✅ nitro-stable	90	0	6
✅ nuxt-stable	90	0	6
✅ sveltekit-stable	90	0	6
✅ vite-stable	90	0	6

✅ 📦 Local Production

App	Passed	Failed	Skipped
✅ astro-stable	90	0	6
✅ express-stable	90	0	6
✅ fastify-stable	90	0	6
✅ hono-stable	90	0	6
✅ nextjs-turbopack-canary	77	0	19
✅ nextjs-turbopack-stable	96	0	0
✅ nextjs-webpack-canary	77	0	19
✅ nextjs-webpack-stable	96	0	0
✅ nitro-stable	90	0	6
✅ nuxt-stable	90	0	6
✅ sveltekit-stable	90	0	6
✅ vite-stable	90	0	6

✅ 🐘 Local Postgres

App	Passed	Failed	Skipped
✅ astro-stable	90	0	6
✅ express-stable	90	0	6
✅ fastify-stable	90	0	6
✅ hono-stable	90	0	6
✅ nextjs-turbopack-canary	77	0	19
✅ nextjs-turbopack-stable	96	0	0
✅ nextjs-webpack-canary	77	0	19
✅ nextjs-webpack-stable	96	0	0
✅ nitro-stable	90	0	6
✅ nuxt-stable	90	0	6
✅ sveltekit-stable	90	0	6
✅ vite-stable	90	0	6

✅ 🪟 Windows

App	Passed	Failed	Skipped
✅ nextjs-turbopack	96	0	0

✅ 📋 Other

App	Passed	Failed	Skipped
✅ e2e-local-dev-nest-stable	90	0	6
✅ e2e-local-postgres-nest-stable	90	0	6
✅ e2e-local-prod-nest-stable	90	0	6

---

📋 View full workflow run

[Copilot]

Pull request overview

This PR hardens @workflow/world-local’s filesystem-backed storage against path traversal by validating request-supplied identifiers before they’re used in file paths, and adds regression tests to cover common traversal payloads.

Changes:

• Introduces assertSafeEntityId (and UnsafeEntityIdError) and applies it across filesystem path composition helpers.
• Adds ID validation at storage entry points (runs/steps/events/hooks) and streamer operations that use IDs in filenames.
• Expands unit + integration coverage to ensure traversal payloads are rejected; adds a changeset for the patch release.

Reviewed changes

Copilot reviewed 9 out of 9 changed files in this pull request and generated 5 comments.

Show a summary per file

File	Description
packages/world-local/src/fs.ts	Adds centralized ID validation + applies it in taggedPath, readJSONWithFallback, and paginatedFileSystemQuery.
packages/world-local/src/streamer.ts	Validates runId and streamName before using them as filename prefixes / keys.
packages/world-local/src/storage/runs-storage.ts	Validates runId before reading run JSON from disk.
packages/world-local/src/storage/steps-storage.ts	Validates runId/stepId before reading steps and before listing by run prefix.
packages/world-local/src/storage/events-storage.ts	Validates runId/eventId and request correlationId before composing composite keys and paths.
packages/world-local/src/storage/hooks-storage.ts	Validates hookId before reading hook JSON from disk.
packages/world-local/src/fs.test.ts	Adds focused tests for assertSafeEntityId and for validation in taggedPath/readJSONWithFallback.
packages/world-local/src/storage.test.ts	Adds regression tests ensuring traversal payloads are rejected across storage APIs.
.changeset/world-local-path-traversal.md	Declares a patch release for the security fix.

---

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[pranaygp]

Solid, well-scoped fix. Validation is applied at every entry point I could trace, tests cover the exact payloads from the Latacora report, and all 328 @workflow/world-local tests pass locally. A few non-blocking suggestions inline — mostly around defense-in-depth and error-type consistency. Copilot already flagged the docstring inaccuracies so I won't duplicate those.

One additional note not worth a line comment: legacy.ts's handleLegacyEvent uses runId in path.join directly (lines 47 and 73 — unchanged by this PR). It's safe today because the function is only called from events.create after assertSafeEntityId('runId', runId) has already run, but the function is exported and nothing in its signature documents that invariant. A one-line assertSafeEntityId('runId', runId) at the top of handleLegacyEvent would make the guarantee local to the file.

[pranaygp]

Two follow-ups not already covered in prior review rounds.

[TooTallNate]

Thanks for the review. Pushed b33b922 addressing every comment:

• UnsafeEntityIdError now extends WorkflowWorldError (with name + static is()) so it flows through the platform's normal error mapping instead of surfacing as a generic 500.
• Added resolveWithinBase(basedir, ...segments) as the belt-and-suspenders containment check, and routed every path.join-with-user-input through it (taggedPath, readJSONWithFallback, all four .locks/** sites in events-storage.ts, and the two sites in legacy.ts).
• handleLegacyEvent now re-asserts runId locally so the invariant is documented at the call site (per your top-level note) and both its path.join sites use resolveWithinBase.
• Error message values are truncated (48 chars + ellipsis) via truncateForError to limit attacker feedback.
• Removed the unused assertSafeEntityIds helper and the unreachable typeof branch.
• Fixed the docstring / example / filePrefix comment inaccuracies Copilot flagged.

Tests: 335 passing in @workflow/world-local (328 → 335, +7 for resolveWithinBase and the WorkflowWorldError hierarchy), 591 passing in @workflow/core.

[TooTallNate]

Summary

• Request-supplied identifiers (runId, eventId, stepId, hookId, correlationId, stream names, and tags) flowed straight into path.join() inside @workflow/world-local, so a client could send a payload like {"runId":"../../../package"} to /.well-known/workflow/v1/flow and read or write files outside the workflow data directory.
• Added a centralized assertSafeEntityId helper in packages/world-local/src/fs.ts that rejects IDs which are empty, start with ., or contain /, \, or NUL bytes. This is permissive enough to accept every existing valid ID shape (ULIDs, composite keys like wrun_X-step_Y, base64url stream namespaces, tags like vitest-0) while blocking real traversal vectors.
• Applied the check at each storage-layer entry point that composes IDs into filesystem paths: fs.taggedPath / readJSONWithFallback / paginatedFileSystemQuery, the runs / steps / events / hooks storage methods, and the streamer.

Test plan

• pnpm --filter @workflow/world-local test — 266 → 328 passing (62 new unit + integration tests covering the exact payloads from the report: ../../../package, ../runs/wrun_…, backslash variants, NUL bytes, .locks, etc.)
• pnpm --filter @workflow/core test — 591 passing

[changeset-bot]

🦋 Changeset detected

Latest commit: 8d3898a

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

This PR includes changesets to release 19 packages

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

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

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

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Project	Deployment	Actions	Updated (UTC)
example-nextjs-workflow-turbopack	Ready	Preview, Comment	Apr 30, 2026 8:43am
example-nextjs-workflow-webpack	Ready	Preview, Comment	Apr 30, 2026 8:43am
example-workflow	Ready	Preview, Comment	Apr 30, 2026 8:43am
workbench-astro-workflow	Ready	Preview, Comment	Apr 30, 2026 8:43am
workbench-express-workflow	Ready	Preview, Comment	Apr 30, 2026 8:43am
workbench-fastify-workflow	Ready	Preview, Comment	Apr 30, 2026 8:43am
workbench-hono-workflow	Ready	Preview, Comment	Apr 30, 2026 8:43am
workbench-nitro-workflow	Ready	Preview, Comment	Apr 30, 2026 8:43am
workbench-nuxt-workflow	Ready	Preview, Comment	Apr 30, 2026 8:43am
workbench-sveltekit-workflow	Ready	Preview, Comment	Apr 30, 2026 8:43am
workbench-vite-workflow	Ready	Preview, Comment	Apr 30, 2026 8:43am
workflow-docs	Ready	Preview, Comment, Open in v0	Apr 30, 2026 8:43am
workflow-swc-playground	Ready	Preview, Comment	Apr 30, 2026 8:43am
workflow-web	Ready	Preview, Comment	Apr 30, 2026 8:43am

[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	🥇 Nitro	0.044s (+2.1%)	1.005s (~)	0.961s	10	1.00x
💻 Local	Express	0.044s (~)	1.005s (~)	0.961s	10	1.00x
🐘 Postgres	Express	0.049s (-15.0% 🟢)	1.009s (~)	0.960s	10	1.12x
🐘 Postgres	Nitro	0.057s (-40.5% 🟢)	1.010s (-3.2%)	0.953s	10	1.29x

workflow with 1 step

💻 Local Development

World	Framework	Workflow Time	Wall Time	Overhead	Samples	vs Fastest
🐘 Postgres	🥇 Express	1.120s (-2.3%)	2.009s (~)	0.889s	10	1.00x
💻 Local	Express	1.126s (~)	2.005s (~)	0.880s	10	1.01x
💻 Local	Nitro	1.129s (~)	2.006s (~)	0.876s	10	1.01x
🐘 Postgres	Nitro	1.135s (~)	2.009s (~)	0.874s	10	1.01x

workflow with 10 sequential steps

💻 Local Development

World	Framework	Workflow Time	Wall Time	Overhead	Samples	vs Fastest
🐘 Postgres	🥇 Express	10.691s (-2.5%)	11.018s (~)	0.327s	3	1.00x
🐘 Postgres	Nitro	10.886s (~)	11.018s (~)	0.132s	3	1.02x
💻 Local	Express	10.937s (~)	11.023s (~)	0.086s	3	1.02x
💻 Local	Nitro	10.947s (~)	11.023s (~)	0.076s	3	1.02x

workflow with 25 sequential steps

💻 Local Development

World	Framework	Workflow Time	Wall Time	Overhead	Samples	vs Fastest
🐘 Postgres	🥇 Express	13.971s (-4.2%)	14.021s (-6.7% 🟢)	0.050s	5	1.00x
🐘 Postgres	Nitro	14.494s (-0.7%)	15.019s (~)	0.525s	4	1.04x
💻 Local	Nitro	14.982s (-0.5%)	15.280s (-4.7%)	0.298s	4	1.07x
💻 Local	Express	14.995s (~)	15.029s (~)	0.034s	4	1.07x

workflow with 50 sequential steps

💻 Local Development

World	Framework	Workflow Time	Wall Time	Overhead	Samples	vs Fastest
🐘 Postgres	🥇 Express	12.932s (-7.7% 🟢)	13.021s (-10.8% 🟢)	0.089s	7	1.00x
🐘 Postgres	Nitro	13.814s (-1.1%)	14.020s (-2.0%)	0.206s	7	1.07x
💻 Local	Nitro	16.416s (-2.2%)	17.031s (~)	0.614s	6	1.27x
💻 Local	Express	16.689s (+0.5%)	17.030s (~)	0.341s	6	1.29x

Promise.all with 10 concurrent steps

💻 Local Development

World	Framework	Workflow Time	Wall Time	Overhead	Samples	vs Fastest
🐘 Postgres	🥇 Express	1.196s (-5.1% 🟢)	2.009s (~)	0.812s	15	1.00x
🐘 Postgres	Nitro	1.253s (-1.7%)	2.009s (~)	0.756s	15	1.05x
💻 Local	Nitro	1.504s (-7.8% 🟢)	2.006s (-3.3%)	0.502s	15	1.26x
💻 Local	Express	1.512s (+1.6%)	2.006s (~)	0.494s	15	1.26x

Promise.all with 25 concurrent steps

💻 Local Development

World	Framework	Workflow Time	Wall Time	Overhead	Samples	vs Fastest
🐘 Postgres	🥇 Express	2.278s (-3.5%)	3.009s (~)	0.731s	10	1.00x
🐘 Postgres	Nitro	2.338s (-0.6%)	3.010s (~)	0.673s	10	1.03x
💻 Local	Nitro	2.828s (-10.0% 🟢)	3.008s (-22.6% 🟢)	0.180s	10	1.24x
💻 Local	Express	2.958s (~)	3.208s (-7.1% 🟢)	0.250s	10	1.30x

Promise.all with 50 concurrent steps

💻 Local Development

World	Framework	Workflow Time	Wall Time	Overhead	Samples	vs Fastest
🐘 Postgres	🥇 Express	3.371s (-3.3%)	4.009s (~)	0.638s	8	1.00x
🐘 Postgres	Nitro	3.455s (-0.7%)	4.010s (~)	0.554s	8	1.03x
💻 Local	Nitro	7.405s (-11.3% 🟢)	8.020s (-11.1% 🟢)	0.614s	4	2.20x
💻 Local	Express	8.209s (-1.6%)	9.022s (~)	0.814s	4	2.44x

Promise.race with 10 concurrent steps

💻 Local Development

World	Framework	Workflow Time	Wall Time	Overhead	Samples	vs Fastest
🐘 Postgres	🥇 Express	1.199s (-4.6%)	2.007s (~)	0.808s	15	1.00x
🐘 Postgres	Nitro	1.260s (~)	2.008s (~)	0.749s	15	1.05x
💻 Local	Express	1.516s (-19.9% 🟢)	2.006s (-15.2% 🟢)	0.489s	15	1.26x
💻 Local	Nitro	1.585s (-15.1% 🟢)	2.006s (-14.3% 🟢)	0.421s	15	1.32x

Promise.race with 25 concurrent steps

💻 Local Development

World	Framework	Workflow Time	Wall Time	Overhead	Samples	vs Fastest
🐘 Postgres	🥇 Express	2.269s (-3.1%)	3.009s (~)	0.740s	10	1.00x
🐘 Postgres	Nitro	2.315s (-1.0%)	3.009s (~)	0.694s	10	1.02x
💻 Local	Nitro	2.903s (-5.3% 🟢)	3.454s (-11.1% 🟢)	0.550s	9	1.28x
💻 Local	Express	3.170s (+1.2%)	4.010s (+6.6% 🔺)	0.840s	8	1.40x

Promise.race with 50 concurrent steps

💻 Local Development

World	Framework	Workflow Time	Wall Time	Overhead	Samples	vs Fastest
🐘 Postgres	🥇 Express	3.388s (-3.2%)	4.008s (~)	0.620s	8	1.00x
🐘 Postgres	Nitro	3.476s (~)	4.009s (~)	0.533s	8	1.03x
💻 Local	Nitro	8.071s (-11.7% 🟢)	9.021s (-10.0% 🟢)	0.950s	4	2.38x
💻 Local	Express	8.942s (+1.6%)	9.276s (~)	0.335s	4	2.64x

workflow with 10 sequential data payload steps (10KB)

💻 Local Development

World	Framework	Workflow Time	Wall Time	Overhead	Samples	vs Fastest
🐘 Postgres	🥇 Express	0.587s (-30.0% 🟢)	1.006s (-1.7%)	0.419s	60	1.00x
🐘 Postgres	Nitro	0.789s (-3.8%)	1.006s (~)	0.216s	60	1.34x
💻 Local	Express	0.987s (~)	1.158s (+7.7% 🔺)	0.171s	52	1.68x
💻 Local	Nitro	1.011s (+3.1%)	1.627s (+48.7% 🔺)	0.616s	37	1.72x

workflow with 25 sequential data payload steps (10KB)

💻 Local Development

World	Framework	Workflow Time	Wall Time	Overhead	Samples	vs Fastest
🐘 Postgres	🥇 Express	1.406s (-28.9% 🟢)	2.007s (-11.1% 🟢)	0.601s	45	1.00x
🐘 Postgres	Nitro	1.886s (-2.2%)	2.030s (-3.4%)	0.144s	45	1.34x
💻 Local	Express	3.040s (+0.8%)	3.609s (+0.7%)	0.569s	25	2.16x
💻 Local	Nitro	3.048s (~)	3.729s (-0.8%)	0.681s	25	2.17x

workflow with 50 sequential data payload steps (10KB)

💻 Local Development

World	Framework	Workflow Time	Wall Time	Overhead	Samples	vs Fastest
🐘 Postgres	🥇 Express	2.926s (-26.7% 🟢)	3.137s (-28.2% 🟢)	0.210s	39	1.00x
🐘 Postgres	Nitro	3.860s (-5.9% 🟢)	4.077s (-11.4% 🟢)	0.218s	30	1.32x
💻 Local	Nitro	8.969s (-3.5%)	9.479s (-5.4% 🟢)	0.510s	13	3.06x
💻 Local	Express	9.232s (~)	9.942s (-0.8%)	0.710s	13	3.15x

workflow with 10 concurrent data payload steps (10KB)

💻 Local Development

World	Framework	Workflow Time	Wall Time	Overhead	Samples	vs Fastest
🐘 Postgres	🥇 Express	0.226s (-20.0% 🟢)	1.007s (~)	0.781s	60	1.00x
🐘 Postgres	Nitro	0.272s (-4.1%)	1.007s (~)	0.735s	60	1.20x
💻 Local	Nitro	0.551s (-8.9% 🟢)	1.004s (-1.7%)	0.454s	60	2.44x
💻 Local	Express	0.578s (+3.2%)	1.004s (~)	0.426s	60	2.56x

workflow with 25 concurrent data payload steps (10KB)

💻 Local Development

World	Framework	Workflow Time	Wall Time	Overhead	Samples	vs Fastest
🐘 Postgres	🥇 Express	0.354s (-30.5% 🟢)	1.006s (~)	0.651s	90	1.00x
🐘 Postgres	Nitro	0.484s (-2.5%)	1.007s (~)	0.523s	90	1.37x
💻 Local	Nitro	2.402s (-5.4% 🟢)	3.009s (~)	0.607s	30	6.78x
💻 Local	Express	2.564s (+2.0%)	3.009s (~)	0.445s	30	7.24x

workflow with 50 concurrent data payload steps (10KB)

💻 Local Development

World	Framework	Workflow Time	Wall Time	Overhead	Samples	vs Fastest
🐘 Postgres	🥇 Express	0.564s (-31.2% 🟢)	1.006s (-1.1%)	0.443s	120	1.00x
🐘 Postgres	Nitro	0.769s (-2.6%)	1.007s (~)	0.238s	120	1.37x
💻 Local	Nitro	10.339s (-7.6% 🟢)	11.028s (-5.5% 🟢)	0.689s	11	18.34x
💻 Local	Express	11.094s (-0.9%)	11.756s (-1.5%)	0.662s	11	19.68x

Stream Benchmarks(includes TTFB metrics)

workflow with stream

💻 Local Development

World	Framework	Workflow Time	TTFB	Slurp	Wall Time	Overhead	Samples	vs Fastest
🐘 Postgres	🥇 Express	0.153s (-25.5% 🟢)	1.000s (~)	0.001s (-31.3% 🟢)	1.009s (~)	0.856s	10	1.00x
💻 Local	Express	0.201s (+0.7%)	1.004s (~)	0.012s (+2.5%)	1.019s (~)	0.818s	10	1.31x
💻 Local	Nitro	0.205s (-3.9%)	1.004s (~)	0.010s (-20.0% 🟢)	1.016s (~)	0.810s	10	1.34x
🐘 Postgres	Nitro	0.208s (+1.6%)	0.995s (~)	0.001s (-6.7% 🟢)	1.009s (~)	0.801s	10	1.36x

stream pipeline with 5 transform steps (1MB)

💻 Local Development

World	Framework	Workflow Time	TTFB	Slurp	Wall Time	Overhead	Samples	vs Fastest
🐘 Postgres	🥇 Express	0.496s (-21.2% 🟢)	1.006s (~)	0.003s (-9.7% 🟢)	1.020s (~)	0.524s	59	1.00x
🐘 Postgres	Nitro	0.597s (-4.4%)	1.007s (~)	0.004s (-5.7% 🟢)	1.021s (~)	0.424s	59	1.20x
💻 Local	Express	0.752s (-0.6%)	1.012s (-1.6%)	0.010s (+1.5%)	1.024s (-1.6%)	0.271s	59	1.52x
💻 Local	Nitro	0.857s (+2.2%)	1.011s (~)	0.009s (-1.4%)	1.115s (~)	0.258s	54	1.73x

10 parallel streams (1MB each)

💻 Local Development

World	Framework	Workflow Time	TTFB	Slurp	Wall Time	Overhead	Samples	vs Fastest
🐘 Postgres	🥇 Express	0.903s (-6.0% 🟢)	1.109s (-13.2% 🟢)	0.000s (+25.5% 🔺)	1.118s (-14.4% 🟢)	0.215s	55	1.00x
🐘 Postgres	Nitro	0.946s (-2.3%)	1.148s (-7.9% 🟢)	0.000s (-53.8% 🟢)	1.161s (-7.7% 🟢)	0.215s	52	1.05x
💻 Local	Nitro	1.208s (-1.2%)	2.020s (~)	0.000s (+233.3% 🔺)	2.022s (~)	0.814s	30	1.34x
💻 Local	Express	1.245s (+1.6%)	2.023s (~)	0.000s (-10.0% 🟢)	2.024s (~)	0.780s	30	1.38x

fan-out fan-in 10 streams (1MB each)

💻 Local Development

World	Framework	Workflow Time	TTFB	Slurp	Wall Time	Overhead	Samples	vs Fastest
🐘 Postgres	🥇 Express	1.629s (-8.1% 🟢)	2.103s (-3.4%)	0.000s (+Infinity% 🔺)	2.112s (-3.9%)	0.483s	29	1.00x
🐘 Postgres	Nitro	1.778s (-0.7%)	2.102s (-1.8%)	0.000s (-100.0% 🟢)	2.113s (-2.8%)	0.335s	29	1.09x
💻 Local	Nitro	3.472s (+2.5%)	4.102s (+1.7%)	0.000s (-25.0% 🟢)	4.104s (+1.7%)	0.632s	15	2.13x
💻 Local	Express	3.573s (+3.1%)	4.099s (+1.6%)	0.001s (-16.7% 🟢)	4.101s (+1.6%)	0.528s	15	2.19x

Summary

Fastest Framework by World

Winner determined by most benchmark wins

World	🥇 Fastest Framework	Wins
💻 Local	Nitro	14/21
🐘 Postgres	Express	21/21

Fastest World by Framework

Winner determined by most benchmark wins

Framework	🥇 Fastest World	Wins
Express	🐘 Postgres	20/21
Nitro	🐘 Postgres	18/21

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
• 🌐 Turso: Community world (local development)
• 🌐 MongoDB: Community world (local development)
• 🌐 Redis: Community world (local development)
• 🌐 Jazz: Community world (local development)

---

📋 View full workflow run

[github-actions]

🧪 E2E Test Results

✅ All tests passed

Summary

	Passed	Failed	Skipped	Total
✅ ▲ Vercel Production	989	0	67	1056
✅ 💻 Local Development	1066	0	86	1152
✅ 📦 Local Production	1066	0	86	1152
✅ 🐘 Local Postgres	1066	0	86	1152
✅ 🪟 Windows	96	0	0	96
✅ 📋 Other	270	0	18	288
Total	4553	0	343	4896

Details by Category

✅ ▲ Vercel Production

App	Passed	Failed	Skipped
✅ astro	89	0	7
✅ example	89	0	7
✅ express	89	0	7
✅ fastify	89	0	7
✅ hono	89	0	7
✅ nextjs-turbopack	94	0	2
✅ nextjs-webpack	94	0	2
✅ nitro	89	0	7
✅ nuxt	89	0	7
✅ sveltekit	89	0	7
✅ vite	89	0	7

✅ 💻 Local Development

App	Passed	Failed	Skipped
✅ astro-stable	90	0	6
✅ express-stable	90	0	6
✅ fastify-stable	90	0	6
✅ hono-stable	90	0	6
✅ nextjs-turbopack-canary	77	0	19
✅ nextjs-turbopack-stable	96	0	0
✅ nextjs-webpack-canary	77	0	19
✅ nextjs-webpack-stable	96	0	0
✅ nitro-stable	90	0	6
✅ nuxt-stable	90	0	6
✅ sveltekit-stable	90	0	6
✅ vite-stable	90	0	6

✅ 📦 Local Production

App	Passed	Failed	Skipped
✅ astro-stable	90	0	6
✅ express-stable	90	0	6
✅ fastify-stable	90	0	6
✅ hono-stable	90	0	6
✅ nextjs-turbopack-canary	77	0	19
✅ nextjs-turbopack-stable	96	0	0
✅ nextjs-webpack-canary	77	0	19
✅ nextjs-webpack-stable	96	0	0
✅ nitro-stable	90	0	6
✅ nuxt-stable	90	0	6
✅ sveltekit-stable	90	0	6
✅ vite-stable	90	0	6

✅ 🐘 Local Postgres

App	Passed	Failed	Skipped
✅ astro-stable	90	0	6
✅ express-stable	90	0	6
✅ fastify-stable	90	0	6
✅ hono-stable	90	0	6
✅ nextjs-turbopack-canary	77	0	19
✅ nextjs-turbopack-stable	96	0	0
✅ nextjs-webpack-canary	77	0	19
✅ nextjs-webpack-stable	96	0	0
✅ nitro-stable	90	0	6
✅ nuxt-stable	90	0	6
✅ sveltekit-stable	90	0	6
✅ vite-stable	90	0	6

✅ 🪟 Windows

App	Passed	Failed	Skipped
✅ nextjs-turbopack	96	0	0

✅ 📋 Other

App	Passed	Failed	Skipped
✅ e2e-local-dev-nest-stable	90	0	6
✅ e2e-local-postgres-nest-stable	90	0	6
✅ e2e-local-prod-nest-stable	90	0	6

---

📋 View full workflow run

[Copilot]

Pull request overview

This PR hardens @workflow/world-local’s filesystem-backed storage against path traversal by validating request-supplied identifiers before they’re used in file paths, and adds regression tests to cover common traversal payloads.

Changes:

• Introduces assertSafeEntityId (and UnsafeEntityIdError) and applies it across filesystem path composition helpers.
• Adds ID validation at storage entry points (runs/steps/events/hooks) and streamer operations that use IDs in filenames.
• Expands unit + integration coverage to ensure traversal payloads are rejected; adds a changeset for the patch release.

Reviewed changes

Copilot reviewed 9 out of 9 changed files in this pull request and generated 5 comments.

Show a summary per file

File	Description
packages/world-local/src/fs.ts	Adds centralized ID validation + applies it in taggedPath, readJSONWithFallback, and paginatedFileSystemQuery.
packages/world-local/src/streamer.ts	Validates runId and streamName before using them as filename prefixes / keys.
packages/world-local/src/storage/runs-storage.ts	Validates runId before reading run JSON from disk.
packages/world-local/src/storage/steps-storage.ts	Validates runId/stepId before reading steps and before listing by run prefix.
packages/world-local/src/storage/events-storage.ts	Validates runId/eventId and request correlationId before composing composite keys and paths.
packages/world-local/src/storage/hooks-storage.ts	Validates hookId before reading hook JSON from disk.
packages/world-local/src/fs.test.ts	Adds focused tests for assertSafeEntityId and for validation in taggedPath/readJSONWithFallback.
packages/world-local/src/storage.test.ts	Adds regression tests ensuring traversal payloads are rejected across storage APIs.
.changeset/world-local-path-traversal.md	Declares a patch release for the security fix.

---

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[pranaygp]

Solid, well-scoped fix. Validation is applied at every entry point I could trace, tests cover the exact payloads from the Latacora report, and all 328 @workflow/world-local tests pass locally. A few non-blocking suggestions inline — mostly around defense-in-depth and error-type consistency. Copilot already flagged the docstring inaccuracies so I won't duplicate those.

One additional note not worth a line comment: legacy.ts's handleLegacyEvent uses runId in path.join directly (lines 47 and 73 — unchanged by this PR). It's safe today because the function is only called from events.create after assertSafeEntityId('runId', runId) has already run, but the function is exported and nothing in its signature documents that invariant. A one-line assertSafeEntityId('runId', runId) at the top of handleLegacyEvent would make the guarantee local to the file.

[pranaygp]

Two follow-ups not already covered in prior review rounds.

[TooTallNate]

Thanks for the review. Pushed b33b922 addressing every comment:

• UnsafeEntityIdError now extends WorkflowWorldError (with name + static is()) so it flows through the platform's normal error mapping instead of surfacing as a generic 500.
• Added resolveWithinBase(basedir, ...segments) as the belt-and-suspenders containment check, and routed every path.join-with-user-input through it (taggedPath, readJSONWithFallback, all four .locks/** sites in events-storage.ts, and the two sites in legacy.ts).
• handleLegacyEvent now re-asserts runId locally so the invariant is documented at the call site (per your top-level note) and both its path.join sites use resolveWithinBase.
• Error message values are truncated (48 chars + ellipsis) via truncateForError to limit attacker feedback.
• Removed the unused assertSafeEntityIds helper and the unreachable typeof branch.
• Fixed the docstring / example / filePrefix comment inaccuracies Copilot flagged.

Tests: 335 passing in @workflow/world-local (328 → 335, +7 for resolveWithinBase and the WorkflowWorldError hierarchy), 591 passing in @workflow/core.

[TooTallNate]

Summary

• Request-supplied identifiers (runId, eventId, stepId, hookId, correlationId, stream names, and tags) flowed straight into path.join() inside @workflow/world-local, so a client could send a payload like {"runId":"../../../package"} to /.well-known/workflow/v1/flow and read or write files outside the workflow data directory.
• Added a centralized assertSafeEntityId helper in packages/world-local/src/fs.ts that rejects IDs which are empty, start with ., or contain /, \, or NUL bytes. This is permissive enough to accept every existing valid ID shape (ULIDs, composite keys like wrun_X-step_Y, base64url stream namespaces, tags like vitest-0) while blocking real traversal vectors.
• Applied the check at each storage-layer entry point that composes IDs into filesystem paths: fs.taggedPath / readJSONWithFallback / paginatedFileSystemQuery, the runs / steps / events / hooks storage methods, and the streamer.

Test plan

• pnpm --filter @workflow/world-local test — 266 → 328 passing (62 new unit + integration tests covering the exact payloads from the report: ../../../package, ../runs/wrun_…, backslash variants, NUL bytes, .locks, etc.)
• pnpm --filter @workflow/core test — 591 passing

[changeset-bot]

🦋 Changeset detected

Latest commit: 8d3898a

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

This PR includes changesets to release 19 packages

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

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

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

[vercel]

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Project	Deployment	Actions	Updated (UTC)
example-nextjs-workflow-turbopack	Ready	Preview, Comment	Apr 30, 2026 8:43am
example-nextjs-workflow-webpack	Ready	Preview, Comment	Apr 30, 2026 8:43am
example-workflow	Ready	Preview, Comment	Apr 30, 2026 8:43am
workbench-astro-workflow	Ready	Preview, Comment	Apr 30, 2026 8:43am
workbench-express-workflow	Ready	Preview, Comment	Apr 30, 2026 8:43am
workbench-fastify-workflow	Ready	Preview, Comment	Apr 30, 2026 8:43am
workbench-hono-workflow	Ready	Preview, Comment	Apr 30, 2026 8:43am
workbench-nitro-workflow	Ready	Preview, Comment	Apr 30, 2026 8:43am
workbench-nuxt-workflow	Ready	Preview, Comment	Apr 30, 2026 8:43am
workbench-sveltekit-workflow	Ready	Preview, Comment	Apr 30, 2026 8:43am
workbench-vite-workflow	Ready	Preview, Comment	Apr 30, 2026 8:43am
workflow-docs	Ready	Preview, Comment, Open in v0	Apr 30, 2026 8:43am
workflow-swc-playground	Ready	Preview, Comment	Apr 30, 2026 8:43am
workflow-web	Ready	Preview, Comment	Apr 30, 2026 8:43am

[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	🥇 Nitro	0.044s (+2.1%)	1.005s (~)	0.961s	10	1.00x
💻 Local	Express	0.044s (~)	1.005s (~)	0.961s	10	1.00x
🐘 Postgres	Express	0.049s (-15.0% 🟢)	1.009s (~)	0.960s	10	1.12x
🐘 Postgres	Nitro	0.057s (-40.5% 🟢)	1.010s (-3.2%)	0.953s	10	1.29x

workflow with 1 step

💻 Local Development

World	Framework	Workflow Time	Wall Time	Overhead	Samples	vs Fastest
🐘 Postgres	🥇 Express	1.120s (-2.3%)	2.009s (~)	0.889s	10	1.00x
💻 Local	Express	1.126s (~)	2.005s (~)	0.880s	10	1.01x
💻 Local	Nitro	1.129s (~)	2.006s (~)	0.876s	10	1.01x
🐘 Postgres	Nitro	1.135s (~)	2.009s (~)	0.874s	10	1.01x

workflow with 10 sequential steps

💻 Local Development

World	Framework	Workflow Time	Wall Time	Overhead	Samples	vs Fastest
🐘 Postgres	🥇 Express	10.691s (-2.5%)	11.018s (~)	0.327s	3	1.00x
🐘 Postgres	Nitro	10.886s (~)	11.018s (~)	0.132s	3	1.02x
💻 Local	Express	10.937s (~)	11.023s (~)	0.086s	3	1.02x
💻 Local	Nitro	10.947s (~)	11.023s (~)	0.076s	3	1.02x

workflow with 25 sequential steps

💻 Local Development

World	Framework	Workflow Time	Wall Time	Overhead	Samples	vs Fastest
🐘 Postgres	🥇 Express	13.971s (-4.2%)	14.021s (-6.7% 🟢)	0.050s	5	1.00x
🐘 Postgres	Nitro	14.494s (-0.7%)	15.019s (~)	0.525s	4	1.04x
💻 Local	Nitro	14.982s (-0.5%)	15.280s (-4.7%)	0.298s	4	1.07x
💻 Local	Express	14.995s (~)	15.029s (~)	0.034s	4	1.07x

workflow with 50 sequential steps

💻 Local Development

World	Framework	Workflow Time	Wall Time	Overhead	Samples	vs Fastest
🐘 Postgres	🥇 Express	12.932s (-7.7% 🟢)	13.021s (-10.8% 🟢)	0.089s	7	1.00x
🐘 Postgres	Nitro	13.814s (-1.1%)	14.020s (-2.0%)	0.206s	7	1.07x
💻 Local	Nitro	16.416s (-2.2%)	17.031s (~)	0.614s	6	1.27x
💻 Local	Express	16.689s (+0.5%)	17.030s (~)	0.341s	6	1.29x

Promise.all with 10 concurrent steps

💻 Local Development

World	Framework	Workflow Time	Wall Time	Overhead	Samples	vs Fastest
🐘 Postgres	🥇 Express	1.196s (-5.1% 🟢)	2.009s (~)	0.812s	15	1.00x
🐘 Postgres	Nitro	1.253s (-1.7%)	2.009s (~)	0.756s	15	1.05x
💻 Local	Nitro	1.504s (-7.8% 🟢)	2.006s (-3.3%)	0.502s	15	1.26x
💻 Local	Express	1.512s (+1.6%)	2.006s (~)	0.494s	15	1.26x

Promise.all with 25 concurrent steps

💻 Local Development

World	Framework	Workflow Time	Wall Time	Overhead	Samples	vs Fastest
🐘 Postgres	🥇 Express	2.278s (-3.5%)	3.009s (~)	0.731s	10	1.00x
🐘 Postgres	Nitro	2.338s (-0.6%)	3.010s (~)	0.673s	10	1.03x
💻 Local	Nitro	2.828s (-10.0% 🟢)	3.008s (-22.6% 🟢)	0.180s	10	1.24x
💻 Local	Express	2.958s (~)	3.208s (-7.1% 🟢)	0.250s	10	1.30x

Promise.all with 50 concurrent steps

💻 Local Development

World	Framework	Workflow Time	Wall Time	Overhead	Samples	vs Fastest
🐘 Postgres	🥇 Express	3.371s (-3.3%)	4.009s (~)	0.638s	8	1.00x
🐘 Postgres	Nitro	3.455s (-0.7%)	4.010s (~)	0.554s	8	1.03x
💻 Local	Nitro	7.405s (-11.3% 🟢)	8.020s (-11.1% 🟢)	0.614s	4	2.20x
💻 Local	Express	8.209s (-1.6%)	9.022s (~)	0.814s	4	2.44x

Promise.race with 10 concurrent steps

💻 Local Development

World	Framework	Workflow Time	Wall Time	Overhead	Samples	vs Fastest
🐘 Postgres	🥇 Express	1.199s (-4.6%)	2.007s (~)	0.808s	15	1.00x
🐘 Postgres	Nitro	1.260s (~)	2.008s (~)	0.749s	15	1.05x
💻 Local	Express	1.516s (-19.9% 🟢)	2.006s (-15.2% 🟢)	0.489s	15	1.26x
💻 Local	Nitro	1.585s (-15.1% 🟢)	2.006s (-14.3% 🟢)	0.421s	15	1.32x

Promise.race with 25 concurrent steps

💻 Local Development

World	Framework	Workflow Time	Wall Time	Overhead	Samples	vs Fastest
🐘 Postgres	🥇 Express	2.269s (-3.1%)	3.009s (~)	0.740s	10	1.00x
🐘 Postgres	Nitro	2.315s (-1.0%)	3.009s (~)	0.694s	10	1.02x
💻 Local	Nitro	2.903s (-5.3% 🟢)	3.454s (-11.1% 🟢)	0.550s	9	1.28x
💻 Local	Express	3.170s (+1.2%)	4.010s (+6.6% 🔺)	0.840s	8	1.40x

Promise.race with 50 concurrent steps

💻 Local Development

World	Framework	Workflow Time	Wall Time	Overhead	Samples	vs Fastest
🐘 Postgres	🥇 Express	3.388s (-3.2%)	4.008s (~)	0.620s	8	1.00x
🐘 Postgres	Nitro	3.476s (~)	4.009s (~)	0.533s	8	1.03x
💻 Local	Nitro	8.071s (-11.7% 🟢)	9.021s (-10.0% 🟢)	0.950s	4	2.38x
💻 Local	Express	8.942s (+1.6%)	9.276s (~)	0.335s	4	2.64x

workflow with 10 sequential data payload steps (10KB)

💻 Local Development

World	Framework	Workflow Time	Wall Time	Overhead	Samples	vs Fastest
🐘 Postgres	🥇 Express	0.587s (-30.0% 🟢)	1.006s (-1.7%)	0.419s	60	1.00x
🐘 Postgres	Nitro	0.789s (-3.8%)	1.006s (~)	0.216s	60	1.34x
💻 Local	Express	0.987s (~)	1.158s (+7.7% 🔺)	0.171s	52	1.68x
💻 Local	Nitro	1.011s (+3.1%)	1.627s (+48.7% 🔺)	0.616s	37	1.72x

workflow with 25 sequential data payload steps (10KB)

💻 Local Development

World	Framework	Workflow Time	Wall Time	Overhead	Samples	vs Fastest
🐘 Postgres	🥇 Express	1.406s (-28.9% 🟢)	2.007s (-11.1% 🟢)	0.601s	45	1.00x
🐘 Postgres	Nitro	1.886s (-2.2%)	2.030s (-3.4%)	0.144s	45	1.34x
💻 Local	Express	3.040s (+0.8%)	3.609s (+0.7%)	0.569s	25	2.16x
💻 Local	Nitro	3.048s (~)	3.729s (-0.8%)	0.681s	25	2.17x

workflow with 50 sequential data payload steps (10KB)

💻 Local Development

World	Framework	Workflow Time	Wall Time	Overhead	Samples	vs Fastest
🐘 Postgres	🥇 Express	2.926s (-26.7% 🟢)	3.137s (-28.2% 🟢)	0.210s	39	1.00x
🐘 Postgres	Nitro	3.860s (-5.9% 🟢)	4.077s (-11.4% 🟢)	0.218s	30	1.32x
💻 Local	Nitro	8.969s (-3.5%)	9.479s (-5.4% 🟢)	0.510s	13	3.06x
💻 Local	Express	9.232s (~)	9.942s (-0.8%)	0.710s	13	3.15x

workflow with 10 concurrent data payload steps (10KB)

💻 Local Development

World	Framework	Workflow Time	Wall Time	Overhead	Samples	vs Fastest
🐘 Postgres	🥇 Express	0.226s (-20.0% 🟢)	1.007s (~)	0.781s	60	1.00x
🐘 Postgres	Nitro	0.272s (-4.1%)	1.007s (~)	0.735s	60	1.20x
💻 Local	Nitro	0.551s (-8.9% 🟢)	1.004s (-1.7%)	0.454s	60	2.44x
💻 Local	Express	0.578s (+3.2%)	1.004s (~)	0.426s	60	2.56x

workflow with 25 concurrent data payload steps (10KB)

💻 Local Development

World	Framework	Workflow Time	Wall Time	Overhead	Samples	vs Fastest
🐘 Postgres	🥇 Express	0.354s (-30.5% 🟢)	1.006s (~)	0.651s	90	1.00x
🐘 Postgres	Nitro	0.484s (-2.5%)	1.007s (~)	0.523s	90	1.37x
💻 Local	Nitro	2.402s (-5.4% 🟢)	3.009s (~)	0.607s	30	6.78x
💻 Local	Express	2.564s (+2.0%)	3.009s (~)	0.445s	30	7.24x

workflow with 50 concurrent data payload steps (10KB)

💻 Local Development

World	Framework	Workflow Time	Wall Time	Overhead	Samples	vs Fastest
🐘 Postgres	🥇 Express	0.564s (-31.2% 🟢)	1.006s (-1.1%)	0.443s	120	1.00x
🐘 Postgres	Nitro	0.769s (-2.6%)	1.007s (~)	0.238s	120	1.37x
💻 Local	Nitro	10.339s (-7.6% 🟢)	11.028s (-5.5% 🟢)	0.689s	11	18.34x
💻 Local	Express	11.094s (-0.9%)	11.756s (-1.5%)	0.662s	11	19.68x

Stream Benchmarks(includes TTFB metrics)

workflow with stream

💻 Local Development

World	Framework	Workflow Time	TTFB	Slurp	Wall Time	Overhead	Samples	vs Fastest
🐘 Postgres	🥇 Express	0.153s (-25.5% 🟢)	1.000s (~)	0.001s (-31.3% 🟢)	1.009s (~)	0.856s	10	1.00x
💻 Local	Express	0.201s (+0.7%)	1.004s (~)	0.012s (+2.5%)	1.019s (~)	0.818s	10	1.31x
💻 Local	Nitro	0.205s (-3.9%)	1.004s (~)	0.010s (-20.0% 🟢)	1.016s (~)	0.810s	10	1.34x
🐘 Postgres	Nitro	0.208s (+1.6%)	0.995s (~)	0.001s (-6.7% 🟢)	1.009s (~)	0.801s	10	1.36x

stream pipeline with 5 transform steps (1MB)

💻 Local Development

World	Framework	Workflow Time	TTFB	Slurp	Wall Time	Overhead	Samples	vs Fastest
🐘 Postgres	🥇 Express	0.496s (-21.2% 🟢)	1.006s (~)	0.003s (-9.7% 🟢)	1.020s (~)	0.524s	59	1.00x
🐘 Postgres	Nitro	0.597s (-4.4%)	1.007s (~)	0.004s (-5.7% 🟢)	1.021s (~)	0.424s	59	1.20x
💻 Local	Express	0.752s (-0.6%)	1.012s (-1.6%)	0.010s (+1.5%)	1.024s (-1.6%)	0.271s	59	1.52x
💻 Local	Nitro	0.857s (+2.2%)	1.011s (~)	0.009s (-1.4%)	1.115s (~)	0.258s	54	1.73x

10 parallel streams (1MB each)

💻 Local Development

World	Framework	Workflow Time	TTFB	Slurp	Wall Time	Overhead	Samples	vs Fastest
🐘 Postgres	🥇 Express	0.903s (-6.0% 🟢)	1.109s (-13.2% 🟢)	0.000s (+25.5% 🔺)	1.118s (-14.4% 🟢)	0.215s	55	1.00x
🐘 Postgres	Nitro	0.946s (-2.3%)	1.148s (-7.9% 🟢)	0.000s (-53.8% 🟢)	1.161s (-7.7% 🟢)	0.215s	52	1.05x
💻 Local	Nitro	1.208s (-1.2%)	2.020s (~)	0.000s (+233.3% 🔺)	2.022s (~)	0.814s	30	1.34x
💻 Local	Express	1.245s (+1.6%)	2.023s (~)	0.000s (-10.0% 🟢)	2.024s (~)	0.780s	30	1.38x

fan-out fan-in 10 streams (1MB each)

💻 Local Development

World	Framework	Workflow Time	TTFB	Slurp	Wall Time	Overhead	Samples	vs Fastest
🐘 Postgres	🥇 Express	1.629s (-8.1% 🟢)	2.103s (-3.4%)	0.000s (+Infinity% 🔺)	2.112s (-3.9%)	0.483s	29	1.00x
🐘 Postgres	Nitro	1.778s (-0.7%)	2.102s (-1.8%)	0.000s (-100.0% 🟢)	2.113s (-2.8%)	0.335s	29	1.09x
💻 Local	Nitro	3.472s (+2.5%)	4.102s (+1.7%)	0.000s (-25.0% 🟢)	4.104s (+1.7%)	0.632s	15	2.13x
💻 Local	Express	3.573s (+3.1%)	4.099s (+1.6%)	0.001s (-16.7% 🟢)	4.101s (+1.6%)	0.528s	15	2.19x

Summary

Fastest Framework by World

Winner determined by most benchmark wins

World	🥇 Fastest Framework	Wins
💻 Local	Nitro	14/21
🐘 Postgres	Express	21/21

Fastest World by Framework

Winner determined by most benchmark wins

Framework	🥇 Fastest World	Wins
Express	🐘 Postgres	20/21
Nitro	🐘 Postgres	18/21

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
• 🌐 Turso: Community world (local development)
• 🌐 MongoDB: Community world (local development)
• 🌐 Redis: Community world (local development)
• 🌐 Jazz: Community world (local development)

---

📋 View full workflow run

[github-actions]

🧪 E2E Test Results

✅ All tests passed

Summary

	Passed	Failed	Skipped	Total
✅ ▲ Vercel Production	989	0	67	1056
✅ 💻 Local Development	1066	0	86	1152
✅ 📦 Local Production	1066	0	86	1152
✅ 🐘 Local Postgres	1066	0	86	1152
✅ 🪟 Windows	96	0	0	96
✅ 📋 Other	270	0	18	288
Total	4553	0	343	4896

Details by Category

✅ ▲ Vercel Production

App	Passed	Failed	Skipped
✅ astro	89	0	7
✅ example	89	0	7
✅ express	89	0	7
✅ fastify	89	0	7
✅ hono	89	0	7
✅ nextjs-turbopack	94	0	2
✅ nextjs-webpack	94	0	2
✅ nitro	89	0	7
✅ nuxt	89	0	7
✅ sveltekit	89	0	7
✅ vite	89	0	7

✅ 💻 Local Development

App	Passed	Failed	Skipped
✅ astro-stable	90	0	6
✅ express-stable	90	0	6
✅ fastify-stable	90	0	6
✅ hono-stable	90	0	6
✅ nextjs-turbopack-canary	77	0	19
✅ nextjs-turbopack-stable	96	0	0
✅ nextjs-webpack-canary	77	0	19
✅ nextjs-webpack-stable	96	0	0
✅ nitro-stable	90	0	6
✅ nuxt-stable	90	0	6
✅ sveltekit-stable	90	0	6
✅ vite-stable	90	0	6

✅ 📦 Local Production

App	Passed	Failed	Skipped
✅ astro-stable	90	0	6
✅ express-stable	90	0	6
✅ fastify-stable	90	0	6
✅ hono-stable	90	0	6
✅ nextjs-turbopack-canary	77	0	19
✅ nextjs-turbopack-stable	96	0	0
✅ nextjs-webpack-canary	77	0	19
✅ nextjs-webpack-stable	96	0	0
✅ nitro-stable	90	0	6
✅ nuxt-stable	90	0	6
✅ sveltekit-stable	90	0	6
✅ vite-stable	90	0	6

✅ 🐘 Local Postgres

App	Passed	Failed	Skipped
✅ astro-stable	90	0	6
✅ express-stable	90	0	6
✅ fastify-stable	90	0	6
✅ hono-stable	90	0	6
✅ nextjs-turbopack-canary	77	0	19
✅ nextjs-turbopack-stable	96	0	0
✅ nextjs-webpack-canary	77	0	19
✅ nextjs-webpack-stable	96	0	0
✅ nitro-stable	90	0	6
✅ nuxt-stable	90	0	6
✅ sveltekit-stable	90	0	6
✅ vite-stable	90	0	6

✅ 🪟 Windows

App	Passed	Failed	Skipped
✅ nextjs-turbopack	96	0	0

✅ 📋 Other

App	Passed	Failed	Skipped
✅ e2e-local-dev-nest-stable	90	0	6
✅ e2e-local-postgres-nest-stable	90	0	6
✅ e2e-local-prod-nest-stable	90	0	6

---

📋 View full workflow run

[Copilot]

Pull request overview

This PR hardens @workflow/world-local’s filesystem-backed storage against path traversal by validating request-supplied identifiers before they’re used in file paths, and adds regression tests to cover common traversal payloads.

Changes:

• Introduces assertSafeEntityId (and UnsafeEntityIdError) and applies it across filesystem path composition helpers.
• Adds ID validation at storage entry points (runs/steps/events/hooks) and streamer operations that use IDs in filenames.
• Expands unit + integration coverage to ensure traversal payloads are rejected; adds a changeset for the patch release.

Reviewed changes

Copilot reviewed 9 out of 9 changed files in this pull request and generated 5 comments.

Show a summary per file

File	Description
packages/world-local/src/fs.ts	Adds centralized ID validation + applies it in taggedPath, readJSONWithFallback, and paginatedFileSystemQuery.
packages/world-local/src/streamer.ts	Validates runId and streamName before using them as filename prefixes / keys.
packages/world-local/src/storage/runs-storage.ts	Validates runId before reading run JSON from disk.
packages/world-local/src/storage/steps-storage.ts	Validates runId/stepId before reading steps and before listing by run prefix.
packages/world-local/src/storage/events-storage.ts	Validates runId/eventId and request correlationId before composing composite keys and paths.
packages/world-local/src/storage/hooks-storage.ts	Validates hookId before reading hook JSON from disk.
packages/world-local/src/fs.test.ts	Adds focused tests for assertSafeEntityId and for validation in taggedPath/readJSONWithFallback.
packages/world-local/src/storage.test.ts	Adds regression tests ensuring traversal payloads are rejected across storage APIs.
.changeset/world-local-path-traversal.md	Declares a patch release for the security fix.

---

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[pranaygp]

Solid, well-scoped fix. Validation is applied at every entry point I could trace, tests cover the exact payloads from the Latacora report, and all 328 @workflow/world-local tests pass locally. A few non-blocking suggestions inline — mostly around defense-in-depth and error-type consistency. Copilot already flagged the docstring inaccuracies so I won't duplicate those.

One additional note not worth a line comment: legacy.ts's handleLegacyEvent uses runId in path.join directly (lines 47 and 73 — unchanged by this PR). It's safe today because the function is only called from events.create after assertSafeEntityId('runId', runId) has already run, but the function is exported and nothing in its signature documents that invariant. A one-line assertSafeEntityId('runId', runId) at the top of handleLegacyEvent would make the guarantee local to the file.

[pranaygp]

Two follow-ups not already covered in prior review rounds.

[TooTallNate]

Thanks for the review. Pushed b33b922 addressing every comment:

• UnsafeEntityIdError now extends WorkflowWorldError (with name + static is()) so it flows through the platform's normal error mapping instead of surfacing as a generic 500.
• Added resolveWithinBase(basedir, ...segments) as the belt-and-suspenders containment check, and routed every path.join-with-user-input through it (taggedPath, readJSONWithFallback, all four .locks/** sites in events-storage.ts, and the two sites in legacy.ts).
• handleLegacyEvent now re-asserts runId locally so the invariant is documented at the call site (per your top-level note) and both its path.join sites use resolveWithinBase.
• Error message values are truncated (48 chars + ellipsis) via truncateForError to limit attacker feedback.
• Removed the unused assertSafeEntityIds helper and the unreachable typeof branch.
• Fixed the docstring / example / filePrefix comment inaccuracies Copilot flagged.

Tests: 335 passing in @workflow/world-local (328 → 335, +7 for resolveWithinBase and the WorkflowWorldError hierarchy), 591 passing in @workflow/core.

[TooTallNate]

Summary

• Request-supplied identifiers (runId, eventId, stepId, hookId, correlationId, stream names, and tags) flowed straight into path.join() inside @workflow/world-local, so a client could send a payload like {"runId":"../../../package"} to /.well-known/workflow/v1/flow and read or write files outside the workflow data directory.
• Added a centralized assertSafeEntityId helper in packages/world-local/src/fs.ts that rejects IDs which are empty, start with ., or contain /, \, or NUL bytes. This is permissive enough to accept every existing valid ID shape (ULIDs, composite keys like wrun_X-step_Y, base64url stream namespaces, tags like vitest-0) while blocking real traversal vectors.
• Applied the check at each storage-layer entry point that composes IDs into filesystem paths: fs.taggedPath / readJSONWithFallback / paginatedFileSystemQuery, the runs / steps / events / hooks storage methods, and the streamer.

Test plan

• pnpm --filter @workflow/world-local test — 266 → 328 passing (62 new unit + integration tests covering the exact payloads from the report: ../../../package, ../runs/wrun_…, backslash variants, NUL bytes, .locks, etc.)
• pnpm --filter @workflow/core test — 591 passing

[changeset-bot]

🦋 Changeset detected

Latest commit: 8d3898a

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

This PR includes changesets to release 19 packages

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

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

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

[vercel]

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

Project	Deployment	Actions	Updated (UTC)
example-nextjs-workflow-turbopack	Ready	Preview, Comment	Apr 30, 2026 8:43am
example-nextjs-workflow-webpack	Ready	Preview, Comment	Apr 30, 2026 8:43am
example-workflow	Ready	Preview, Comment	Apr 30, 2026 8:43am
workbench-astro-workflow	Ready	Preview, Comment	Apr 30, 2026 8:43am
workbench-express-workflow	Ready	Preview, Comment	Apr 30, 2026 8:43am
workbench-fastify-workflow	Ready	Preview, Comment	Apr 30, 2026 8:43am
workbench-hono-workflow	Ready	Preview, Comment	Apr 30, 2026 8:43am
workbench-nitro-workflow	Ready	Preview, Comment	Apr 30, 2026 8:43am
workbench-nuxt-workflow	Ready	Preview, Comment	Apr 30, 2026 8:43am
workbench-sveltekit-workflow	Ready	Preview, Comment	Apr 30, 2026 8:43am
workbench-vite-workflow	Ready	Preview, Comment	Apr 30, 2026 8:43am
workflow-docs	Ready	Preview, Comment, Open in v0	Apr 30, 2026 8:43am
workflow-swc-playground	Ready	Preview, Comment	Apr 30, 2026 8:43am
workflow-web	Ready	Preview, Comment	Apr 30, 2026 8:43am

[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	🥇 Nitro	0.044s (+2.1%)	1.005s (~)	0.961s	10	1.00x
💻 Local	Express	0.044s (~)	1.005s (~)	0.961s	10	1.00x
🐘 Postgres	Express	0.049s (-15.0% 🟢)	1.009s (~)	0.960s	10	1.12x
🐘 Postgres	Nitro	0.057s (-40.5% 🟢)	1.010s (-3.2%)	0.953s	10	1.29x

workflow with 1 step

💻 Local Development

World	Framework	Workflow Time	Wall Time	Overhead	Samples	vs Fastest
🐘 Postgres	🥇 Express	1.120s (-2.3%)	2.009s (~)	0.889s	10	1.00x
💻 Local	Express	1.126s (~)	2.005s (~)	0.880s	10	1.01x
💻 Local	Nitro	1.129s (~)	2.006s (~)	0.876s	10	1.01x
🐘 Postgres	Nitro	1.135s (~)	2.009s (~)	0.874s	10	1.01x

workflow with 10 sequential steps

💻 Local Development

World	Framework	Workflow Time	Wall Time	Overhead	Samples	vs Fastest
🐘 Postgres	🥇 Express	10.691s (-2.5%)	11.018s (~)	0.327s	3	1.00x
🐘 Postgres	Nitro	10.886s (~)	11.018s (~)	0.132s	3	1.02x
💻 Local	Express	10.937s (~)	11.023s (~)	0.086s	3	1.02x
💻 Local	Nitro	10.947s (~)	11.023s (~)	0.076s	3	1.02x

workflow with 25 sequential steps

💻 Local Development

World	Framework	Workflow Time	Wall Time	Overhead	Samples	vs Fastest
🐘 Postgres	🥇 Express	13.971s (-4.2%)	14.021s (-6.7% 🟢)	0.050s	5	1.00x
🐘 Postgres	Nitro	14.494s (-0.7%)	15.019s (~)	0.525s	4	1.04x
💻 Local	Nitro	14.982s (-0.5%)	15.280s (-4.7%)	0.298s	4	1.07x
💻 Local	Express	14.995s (~)	15.029s (~)	0.034s	4	1.07x

workflow with 50 sequential steps

💻 Local Development

World	Framework	Workflow Time	Wall Time	Overhead	Samples	vs Fastest
🐘 Postgres	🥇 Express	12.932s (-7.7% 🟢)	13.021s (-10.8% 🟢)	0.089s	7	1.00x
🐘 Postgres	Nitro	13.814s (-1.1%)	14.020s (-2.0%)	0.206s	7	1.07x
💻 Local	Nitro	16.416s (-2.2%)	17.031s (~)	0.614s	6	1.27x
💻 Local	Express	16.689s (+0.5%)	17.030s (~)	0.341s	6	1.29x

Promise.all with 10 concurrent steps

💻 Local Development

World	Framework	Workflow Time	Wall Time	Overhead	Samples	vs Fastest
🐘 Postgres	🥇 Express	1.196s (-5.1% 🟢)	2.009s (~)	0.812s	15	1.00x
🐘 Postgres	Nitro	1.253s (-1.7%)	2.009s (~)	0.756s	15	1.05x
💻 Local	Nitro	1.504s (-7.8% 🟢)	2.006s (-3.3%)	0.502s	15	1.26x
💻 Local	Express	1.512s (+1.6%)	2.006s (~)	0.494s	15	1.26x

Promise.all with 25 concurrent steps

💻 Local Development

World	Framework	Workflow Time	Wall Time	Overhead	Samples	vs Fastest
🐘 Postgres	🥇 Express	2.278s (-3.5%)	3.009s (~)	0.731s	10	1.00x
🐘 Postgres	Nitro	2.338s (-0.6%)	3.010s (~)	0.673s	10	1.03x
💻 Local	Nitro	2.828s (-10.0% 🟢)	3.008s (-22.6% 🟢)	0.180s	10	1.24x
💻 Local	Express	2.958s (~)	3.208s (-7.1% 🟢)	0.250s	10	1.30x

Promise.all with 50 concurrent steps

💻 Local Development

World	Framework	Workflow Time	Wall Time	Overhead	Samples	vs Fastest
🐘 Postgres	🥇 Express	3.371s (-3.3%)	4.009s (~)	0.638s	8	1.00x
🐘 Postgres	Nitro	3.455s (-0.7%)	4.010s (~)	0.554s	8	1.03x
💻 Local	Nitro	7.405s (-11.3% 🟢)	8.020s (-11.1% 🟢)	0.614s	4	2.20x
💻 Local	Express	8.209s (-1.6%)	9.022s (~)	0.814s	4	2.44x

Promise.race with 10 concurrent steps

💻 Local Development

World	Framework	Workflow Time	Wall Time	Overhead	Samples	vs Fastest
🐘 Postgres	🥇 Express	1.199s (-4.6%)	2.007s (~)	0.808s	15	1.00x
🐘 Postgres	Nitro	1.260s (~)	2.008s (~)	0.749s	15	1.05x
💻 Local	Express	1.516s (-19.9% 🟢)	2.006s (-15.2% 🟢)	0.489s	15	1.26x
💻 Local	Nitro	1.585s (-15.1% 🟢)	2.006s (-14.3% 🟢)	0.421s	15	1.32x

Promise.race with 25 concurrent steps

💻 Local Development

World	Framework	Workflow Time	Wall Time	Overhead	Samples	vs Fastest
🐘 Postgres	🥇 Express	2.269s (-3.1%)	3.009s (~)	0.740s	10	1.00x
🐘 Postgres	Nitro	2.315s (-1.0%)	3.009s (~)	0.694s	10	1.02x
💻 Local	Nitro	2.903s (-5.3% 🟢)	3.454s (-11.1% 🟢)	0.550s	9	1.28x
💻 Local	Express	3.170s (+1.2%)	4.010s (+6.6% 🔺)	0.840s	8	1.40x

Promise.race with 50 concurrent steps

💻 Local Development

World	Framework	Workflow Time	Wall Time	Overhead	Samples	vs Fastest
🐘 Postgres	🥇 Express	3.388s (-3.2%)	4.008s (~)	0.620s	8	1.00x
🐘 Postgres	Nitro	3.476s (~)	4.009s (~)	0.533s	8	1.03x
💻 Local	Nitro	8.071s (-11.7% 🟢)	9.021s (-10.0% 🟢)	0.950s	4	2.38x
💻 Local	Express	8.942s (+1.6%)	9.276s (~)	0.335s	4	2.64x

workflow with 10 sequential data payload steps (10KB)

💻 Local Development

World	Framework	Workflow Time	Wall Time	Overhead	Samples	vs Fastest
🐘 Postgres	🥇 Express	0.587s (-30.0% 🟢)	1.006s (-1.7%)	0.419s	60	1.00x
🐘 Postgres	Nitro	0.789s (-3.8%)	1.006s (~)	0.216s	60	1.34x
💻 Local	Express	0.987s (~)	1.158s (+7.7% 🔺)	0.171s	52	1.68x
💻 Local	Nitro	1.011s (+3.1%)	1.627s (+48.7% 🔺)	0.616s	37	1.72x

workflow with 25 sequential data payload steps (10KB)

💻 Local Development

World	Framework	Workflow Time	Wall Time	Overhead	Samples	vs Fastest
🐘 Postgres	🥇 Express	1.406s (-28.9% 🟢)	2.007s (-11.1% 🟢)	0.601s	45	1.00x
🐘 Postgres	Nitro	1.886s (-2.2%)	2.030s (-3.4%)	0.144s	45	1.34x
💻 Local	Express	3.040s (+0.8%)	3.609s (+0.7%)	0.569s	25	2.16x
💻 Local	Nitro	3.048s (~)	3.729s (-0.8%)	0.681s	25	2.17x

workflow with 50 sequential data payload steps (10KB)

💻 Local Development

World	Framework	Workflow Time	Wall Time	Overhead	Samples	vs Fastest
🐘 Postgres	🥇 Express	2.926s (-26.7% 🟢)	3.137s (-28.2% 🟢)	0.210s	39	1.00x
🐘 Postgres	Nitro	3.860s (-5.9% 🟢)	4.077s (-11.4% 🟢)	0.218s	30	1.32x
💻 Local	Nitro	8.969s (-3.5%)	9.479s (-5.4% 🟢)	0.510s	13	3.06x
💻 Local	Express	9.232s (~)	9.942s (-0.8%)	0.710s	13	3.15x

workflow with 10 concurrent data payload steps (10KB)

💻 Local Development

World	Framework	Workflow Time	Wall Time	Overhead	Samples	vs Fastest
🐘 Postgres	🥇 Express	0.226s (-20.0% 🟢)	1.007s (~)	0.781s	60	1.00x
🐘 Postgres	Nitro	0.272s (-4.1%)	1.007s (~)	0.735s	60	1.20x
💻 Local	Nitro	0.551s (-8.9% 🟢)	1.004s (-1.7%)	0.454s	60	2.44x
💻 Local	Express	0.578s (+3.2%)	1.004s (~)	0.426s	60	2.56x

workflow with 25 concurrent data payload steps (10KB)

💻 Local Development

World	Framework	Workflow Time	Wall Time	Overhead	Samples	vs Fastest
🐘 Postgres	🥇 Express	0.354s (-30.5% 🟢)	1.006s (~)	0.651s	90	1.00x
🐘 Postgres	Nitro	0.484s (-2.5%)	1.007s (~)	0.523s	90	1.37x
💻 Local	Nitro	2.402s (-5.4% 🟢)	3.009s (~)	0.607s	30	6.78x
💻 Local	Express	2.564s (+2.0%)	3.009s (~)	0.445s	30	7.24x

workflow with 50 concurrent data payload steps (10KB)

💻 Local Development

World	Framework	Workflow Time	Wall Time	Overhead	Samples	vs Fastest
🐘 Postgres	🥇 Express	0.564s (-31.2% 🟢)	1.006s (-1.1%)	0.443s	120	1.00x
🐘 Postgres	Nitro	0.769s (-2.6%)	1.007s (~)	0.238s	120	1.37x
💻 Local	Nitro	10.339s (-7.6% 🟢)	11.028s (-5.5% 🟢)	0.689s	11	18.34x
💻 Local	Express	11.094s (-0.9%)	11.756s (-1.5%)	0.662s	11	19.68x

Stream Benchmarks(includes TTFB metrics)

workflow with stream

💻 Local Development

World	Framework	Workflow Time	TTFB	Slurp	Wall Time	Overhead	Samples	vs Fastest
🐘 Postgres	🥇 Express	0.153s (-25.5% 🟢)	1.000s (~)	0.001s (-31.3% 🟢)	1.009s (~)	0.856s	10	1.00x
💻 Local	Express	0.201s (+0.7%)	1.004s (~)	0.012s (+2.5%)	1.019s (~)	0.818s	10	1.31x
💻 Local	Nitro	0.205s (-3.9%)	1.004s (~)	0.010s (-20.0% 🟢)	1.016s (~)	0.810s	10	1.34x
🐘 Postgres	Nitro	0.208s (+1.6%)	0.995s (~)	0.001s (-6.7% 🟢)	1.009s (~)	0.801s	10	1.36x

stream pipeline with 5 transform steps (1MB)

💻 Local Development

World	Framework	Workflow Time	TTFB	Slurp	Wall Time	Overhead	Samples	vs Fastest
🐘 Postgres	🥇 Express	0.496s (-21.2% 🟢)	1.006s (~)	0.003s (-9.7% 🟢)	1.020s (~)	0.524s	59	1.00x
🐘 Postgres	Nitro	0.597s (-4.4%)	1.007s (~)	0.004s (-5.7% 🟢)	1.021s (~)	0.424s	59	1.20x
💻 Local	Express	0.752s (-0.6%)	1.012s (-1.6%)	0.010s (+1.5%)	1.024s (-1.6%)	0.271s	59	1.52x
💻 Local	Nitro	0.857s (+2.2%)	1.011s (~)	0.009s (-1.4%)	1.115s (~)	0.258s	54	1.73x

10 parallel streams (1MB each)

💻 Local Development

World	Framework	Workflow Time	TTFB	Slurp	Wall Time	Overhead	Samples	vs Fastest
🐘 Postgres	🥇 Express	0.903s (-6.0% 🟢)	1.109s (-13.2% 🟢)	0.000s (+25.5% 🔺)	1.118s (-14.4% 🟢)	0.215s	55	1.00x
🐘 Postgres	Nitro	0.946s (-2.3%)	1.148s (-7.9% 🟢)	0.000s (-53.8% 🟢)	1.161s (-7.7% 🟢)	0.215s	52	1.05x
💻 Local	Nitro	1.208s (-1.2%)	2.020s (~)	0.000s (+233.3% 🔺)	2.022s (~)	0.814s	30	1.34x
💻 Local	Express	1.245s (+1.6%)	2.023s (~)	0.000s (-10.0% 🟢)	2.024s (~)	0.780s	30	1.38x

fan-out fan-in 10 streams (1MB each)

💻 Local Development

World	Framework	Workflow Time	TTFB	Slurp	Wall Time	Overhead	Samples	vs Fastest
🐘 Postgres	🥇 Express	1.629s (-8.1% 🟢)	2.103s (-3.4%)	0.000s (+Infinity% 🔺)	2.112s (-3.9%)	0.483s	29	1.00x
🐘 Postgres	Nitro	1.778s (-0.7%)	2.102s (-1.8%)	0.000s (-100.0% 🟢)	2.113s (-2.8%)	0.335s	29	1.09x
💻 Local	Nitro	3.472s (+2.5%)	4.102s (+1.7%)	0.000s (-25.0% 🟢)	4.104s (+1.7%)	0.632s	15	2.13x
💻 Local	Express	3.573s (+3.1%)	4.099s (+1.6%)	0.001s (-16.7% 🟢)	4.101s (+1.6%)	0.528s	15	2.19x

Summary

Fastest Framework by World

Winner determined by most benchmark wins

World	🥇 Fastest Framework	Wins
💻 Local	Nitro	14/21
🐘 Postgres	Express	21/21

Fastest World by Framework

Winner determined by most benchmark wins

Framework	🥇 Fastest World	Wins
Express	🐘 Postgres	20/21
Nitro	🐘 Postgres	18/21

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
• 🌐 Turso: Community world (local development)
• 🌐 MongoDB: Community world (local development)
• 🌐 Redis: Community world (local development)
• 🌐 Jazz: Community world (local development)

---

📋 View full workflow run

[github-actions]

🧪 E2E Test Results

✅ All tests passed

Summary

	Passed	Failed	Skipped	Total
✅ ▲ Vercel Production	989	0	67	1056
✅ 💻 Local Development	1066	0	86	1152
✅ 📦 Local Production	1066	0	86	1152
✅ 🐘 Local Postgres	1066	0	86	1152
✅ 🪟 Windows	96	0	0	96
✅ 📋 Other	270	0	18	288
Total	4553	0	343	4896

Details by Category

✅ ▲ Vercel Production

App	Passed	Failed	Skipped
✅ astro	89	0	7
✅ example	89	0	7
✅ express	89	0	7
✅ fastify	89	0	7
✅ hono	89	0	7
✅ nextjs-turbopack	94	0	2
✅ nextjs-webpack	94	0	2
✅ nitro	89	0	7
✅ nuxt	89	0	7
✅ sveltekit	89	0	7
✅ vite	89	0	7

✅ 💻 Local Development

App	Passed	Failed	Skipped
✅ astro-stable	90	0	6
✅ express-stable	90	0	6
✅ fastify-stable	90	0	6
✅ hono-stable	90	0	6
✅ nextjs-turbopack-canary	77	0	19
✅ nextjs-turbopack-stable	96	0	0
✅ nextjs-webpack-canary	77	0	19
✅ nextjs-webpack-stable	96	0	0
✅ nitro-stable	90	0	6
✅ nuxt-stable	90	0	6
✅ sveltekit-stable	90	0	6
✅ vite-stable	90	0	6

✅ 📦 Local Production

App	Passed	Failed	Skipped
✅ astro-stable	90	0	6
✅ express-stable	90	0	6
✅ fastify-stable	90	0	6
✅ hono-stable	90	0	6
✅ nextjs-turbopack-canary	77	0	19
✅ nextjs-turbopack-stable	96	0	0
✅ nextjs-webpack-canary	77	0	19
✅ nextjs-webpack-stable	96	0	0
✅ nitro-stable	90	0	6
✅ nuxt-stable	90	0	6
✅ sveltekit-stable	90	0	6
✅ vite-stable	90	0	6

✅ 🐘 Local Postgres

App	Passed	Failed	Skipped
✅ astro-stable	90	0	6
✅ express-stable	90	0	6
✅ fastify-stable	90	0	6
✅ hono-stable	90	0	6
✅ nextjs-turbopack-canary	77	0	19
✅ nextjs-turbopack-stable	96	0	0
✅ nextjs-webpack-canary	77	0	19
✅ nextjs-webpack-stable	96	0	0
✅ nitro-stable	90	0	6
✅ nuxt-stable	90	0	6
✅ sveltekit-stable	90	0	6
✅ vite-stable	90	0	6

✅ 🪟 Windows

App	Passed	Failed	Skipped
✅ nextjs-turbopack	96	0	0

✅ 📋 Other

App	Passed	Failed	Skipped
✅ e2e-local-dev-nest-stable	90	0	6
✅ e2e-local-postgres-nest-stable	90	0	6
✅ e2e-local-prod-nest-stable	90	0	6

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[Copilot]

Pull request overview

This PR hardens @workflow/world-local’s filesystem-backed storage against path traversal by validating request-supplied identifiers before they’re used in file paths, and adds regression tests to cover common traversal payloads.

Changes:

• Introduces assertSafeEntityId (and UnsafeEntityIdError) and applies it across filesystem path composition helpers.
• Adds ID validation at storage entry points (runs/steps/events/hooks) and streamer operations that use IDs in filenames.
• Expands unit + integration coverage to ensure traversal payloads are rejected; adds a changeset for the patch release.

Reviewed changes

Copilot reviewed 9 out of 9 changed files in this pull request and generated 5 comments.

Show a summary per file

File	Description
packages/world-local/src/fs.ts	Adds centralized ID validation + applies it in taggedPath, readJSONWithFallback, and paginatedFileSystemQuery.
packages/world-local/src/streamer.ts	Validates runId and streamName before using them as filename prefixes / keys.
packages/world-local/src/storage/runs-storage.ts	Validates runId before reading run JSON from disk.
packages/world-local/src/storage/steps-storage.ts	Validates runId/stepId before reading steps and before listing by run prefix.
packages/world-local/src/storage/events-storage.ts	Validates runId/eventId and request correlationId before composing composite keys and paths.
packages/world-local/src/storage/hooks-storage.ts	Validates hookId before reading hook JSON from disk.
packages/world-local/src/fs.test.ts	Adds focused tests for assertSafeEntityId and for validation in taggedPath/readJSONWithFallback.
packages/world-local/src/storage.test.ts	Adds regression tests ensuring traversal payloads are rejected across storage APIs.
.changeset/world-local-path-traversal.md	Declares a patch release for the security fix.

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[pranaygp]

Solid, well-scoped fix. Validation is applied at every entry point I could trace, tests cover the exact payloads from the Latacora report, and all 328 @workflow/world-local tests pass locally. A few non-blocking suggestions inline — mostly around defense-in-depth and error-type consistency. Copilot already flagged the docstring inaccuracies so I won't duplicate those.

One additional note not worth a line comment: legacy.ts's handleLegacyEvent uses runId in path.join directly (lines 47 and 73 — unchanged by this PR). It's safe today because the function is only called from events.create after assertSafeEntityId('runId', runId) has already run, but the function is exported and nothing in its signature documents that invariant. A one-line assertSafeEntityId('runId', runId) at the top of handleLegacyEvent would make the guarantee local to the file.

[pranaygp]

Two follow-ups not already covered in prior review rounds.

[TooTallNate]

Thanks for the review. Pushed b33b922 addressing every comment:

• UnsafeEntityIdError now extends WorkflowWorldError (with name + static is()) so it flows through the platform's normal error mapping instead of surfacing as a generic 500.
• Added resolveWithinBase(basedir, ...segments) as the belt-and-suspenders containment check, and routed every path.join-with-user-input through it (taggedPath, readJSONWithFallback, all four .locks/** sites in events-storage.ts, and the two sites in legacy.ts).
• handleLegacyEvent now re-asserts runId locally so the invariant is documented at the call site (per your top-level note) and both its path.join sites use resolveWithinBase.
• Error message values are truncated (48 chars + ellipsis) via truncateForError to limit attacker feedback.
• Removed the unused assertSafeEntityIds helper and the unreachable typeof branch.
• Fixed the docstring / example / filePrefix comment inaccuracies Copilot flagged.

Tests: 335 passing in @workflow/world-local (328 → 335, +7 for resolveWithinBase and the WorkflowWorldError hierarchy), 591 passing in @workflow/core.