* refactor(swc-plugin): remove client transform mode, merge into step mode
Remove the `client` transform mode from the SWC compiler plugin. The
`client` and `step` modes were nearly identical — both preserved step
function bodies, replaced workflow bodies with throw stubs, and emitted
the same JSON manifest. Step mode now absorbs all client-mode behaviors:
- Dead code elimination (previously only workflow + client)
- Hoisted variable references for object property steps
- All integrations use mode: 'step' instead of 'client'
BREAKING CHANGE: The `client` value for the SWC plugin `mode` option is
no longer accepted. Use `step` instead.
* fix(nitro): force-inline workflow packages in dev mode for serde classId registration
In dev mode, Nitro's Rollup externalizes npm packages like @workflow/core,
so the SWC transform plugin never processes files like run.js. This means
serde classes (e.g. Run) never get the classId registration IIFE, causing
serialization failures when step functions return Run instances.
Uses a Rollup resolveId hook to force workflow SDK packages to be bundled
(non-external) while leaving all other dependencies external. This is more
targeted than noExternals=true which bundles everything and causes TDZ
errors from circular imports in packages like vue-bundle-renderer/h3.
The Nitro module now also ignores .nitro/workflow/** in watchOptions so
writing generated workflow bundles does not retrigger Nitro's own dev
bundle rebuild loop.
Also wraps dev:reload workflow rebuilds and makes LocalBuilder.build()
atomic (writes to temp files, renames on success) to avoid partial output
state during HMR.
For Nuxt, also configures Vite's ssr.noExternal to bundle workflow
packages in the SSR context.
* fix(nitro,nuxt): address review feedback on dev-mode classId fix
- nitro builders: use crypto.randomUUID() for temp file suffix instead of
Date.now() to avoid collisions under rapid/concurrent build() calls,
and serialize concurrent build() calls through an internal queue so
two overlapping dev rebuilds cannot clobber each other's temp outputs.
- nitro index: use fileURLToPath() to convert file:// URLs to filesystem
paths, which correctly handles Windows paths (file:///C:/... -> C:\...)
and percent-decoding, instead of relying on new URL(...).pathname.
- nuxt module: normalize vite.ssr.noExternal to an array (preserving any
existing string/RegExp/array entry) before appending workflow package
matchers, so the force-bundle behavior is not a no-op when noExternal
is already set to a non-array value.
## Summary
When `WORKFLOW_PUBLIC_MANIFEST=1` is set, each framework builder exposes the workflow manifest at `/.well-known/workflow/v1/manifest.json` via the most appropriate mechanism for the framework:
- **Next.js**: Copies manifest to `public/.well-known/workflow/v1/manifest.json` (served as a static file)
- **SvelteKit**: Copies manifest to `static/.well-known/workflow/v1/manifest.json` (served as a static file)
- **Vercel Build Output API** (example workbench): Copies manifest to `.vercel/output/static/.well-known/workflow/v1/manifest.json` (served as a static file)
- **Nitro** (vite, hono, express, fastify, nuxt, nitro-v2, nitro-v3): Registers a virtual handler that reads and serves the manifest JSON
- **Astro**: Generates a `manifest.json.js` page route that returns the manifest JSON
- **NestJS**: Adds a `@Get('manifest.json')` endpoint on the `WorkflowController` (gated by the env var at runtime)
### Other changes
- `BaseBuilder.createManifest()` now returns the manifest JSON string so framework builders can use it
- Added `shouldExposePublicManifest` getter to `BaseBuilder`
- Fixed Astro `LocalBuilder` which was missing the `createManifest()` call that all other framework builders have
- Removed unused `public/` directory and static file copy from the example workbench build script
- Added `WORKFLOW_PUBLIC_MANIFEST` to `turbo.json` build task env so Vercel builds can access it
- Added generated manifest paths to `.gitignore`
Fixed a bug in module specifier resolution and added support for package subpath exports in workflow IDs.
### What changed?
- Fixed a caching bug in the module specifier resolution system that could cause incorrect IDs
- Added support for subpath exports in package IDs (e.g., `workflow/internal/builtins@4.0.0`)
- Improved module resolution by passing absolute file paths to the SWC transform
- Enhanced manifest merging to properly combine results from both workflow and step bundles
- Updated builders to return and merge manifests from both workflow and step bundles
### How to test?
1. Build a project that uses subpath exports in packages
2. Verify that workflow IDs correctly include the subpath (e.g., `workflow/internal/builtins@4.0.0`)
3. Test with a project that has multiple builds to ensure module specifier caching works correctly
### Why make this change?
This change addresses an issue where the module specifier cache could return incorrect results, leading to inconsistent workflow IDs. It also adds support for packages with multiple entry points through subpath exports, ensuring that steps with the same name in different subpaths don't collide. This improves the reliability of cross-bundle references and makes the system more robust when working with complex package structures.
Peter Wielander