Build: No dts-mapper files during dev

[ndelangen]

What I did

We can use this functionality:
https://www.typescriptlang.org/tsconfig/#customConditions

To skip on generating the dts mapper files we had.
It might eliminate a race-condition we had at compile very occasionally, example:
https://app.circleci.com/pipelines/github/storybookjs/storybook/114019/workflows/4466ed1c-e3b6-4e91-990d-12a24fd4518d/jobs/1067742

Checklist for Contributors

Testing

The changes in this PR are covered in the following automated tests:

• stories
• unit tests
• integration tests
• end-to-end tests

Manual testing

• Run a local compile locally (in normal link mode)
• Check if type definitions are present (they should not)
• Restart TypeScript language server, wait for it to load again
• Check if an import such as this: import { Button, Link, SyntaxHighlighter } from 'storybook/internal/components'; retains it's type-safely, and allows you to jump to source/definitions (they should now be the same thing)

Documentation

• Add or update documentation reflecting your changes
• If you are deprecating/removing a feature, make sure to update
  MIGRATION.MD

Checklist for Maintainers

• When this PR is ready for testing, make sure to add ci:normal, ci:merged or ci:daily GH label to it to run a specific set of sandboxes. The particular set of sandboxes can be found in code/lib/cli-storybook/src/sandbox-templates.ts

• Make sure this PR contains one of the labels below:

  Available labels

  • bug: Internal changes that fixes incorrect behavior.
  • maintenance: User-facing maintenance tasks.
  • dependencies: Upgrading (sometimes downgrading) dependencies.
  • build: Internal-facing build tooling & test updates. Will not show up in release changelog.
  • cleanup: Minor cleanup style change. Will not show up in release changelog.
  • documentation: Documentation only changes. Will not show up in release changelog.
  • feature request: Introducing a new feature.
  • BREAKING CHANGE: Changes that break compatibility in some way with current major version.
  • other: Changes that don't fit in the above categories.

🦋 Canary release

This PR does not have a canary release associated. You can request a canary release of this pull request by mentioning the @storybookjs/core team here.

core team members can create a canary release here or locally with gh workflow run --repo storybookjs/storybook publish.yml --field pr=<PR_NUMBER>

Summary by CodeRabbit

• Chores
  • Enhanced package exports to include source code references, enabling better tooling integration and source map support across the framework and related packages.
  • Updated build configuration and streamlined type generation pipeline for improved build efficiency.

[nx-cloud]

View your CI Pipeline Execution ↗ for commit e8d4488

Command	Status	Duration	Result
nx run-many -t compile,check,knip,test,pretty-d...	✅ Succeeded	14m 11s	View ↗

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☁️ Nx Cloud last updated this comment at 2026-02-03 10:34:58 UTC

[coderabbitai]

📝 Walkthrough

Walkthrough

This pull request systematically adds "code" export fields to package.json files across the codebase, pointing to TypeScript source files. Accompanying build changes update export map generation and remove the type mapper utility that is no longer needed with the new export structure.

Changes

Cohort / File(s)	Summary
Addon Packages code/addons/a11y/package.json, code/addons/docs/package.json, code/addons/links/package.json, code/addons/onboarding/package.json, code/addons/pseudo-states/package.json, code/addons/themes/package.json, code/addons/vitest/package.json	Added "code" export fields pointing to TypeScript source files for each addon's main and secondary exports (e.g., "./preview", "./vitest-plugin").
Builder Packages code/builders/builder-vite/package.json, code/builders/builder-webpack5/package.json	Added "code" export field pointing to "./src/index.ts" for main export entry.
Core Package code/core/package.json	Added "code" export fields for 33+ export paths, including main entry, framework integrations, internal modules, and preview/manager APIs, each pointing to corresponding TypeScript source files.
Framework Packages code/frameworks/angular/package.json, code/frameworks/ember/package.json, code/frameworks/html-vite/package.json, code/frameworks/nextjs-vite/package.json, code/frameworks/nextjs/package.json, code/frameworks/preact-vite/package.json, code/frameworks/react-native-web-vite/package.json, code/frameworks/react-vite/package.json, code/frameworks/react-webpack5/package.json, code/frameworks/server-webpack5/package.json, code/frameworks/svelte-vite/package.json, code/frameworks/sveltekit/package.json, code/frameworks/vue3-vite/package.json, code/frameworks/web-components-vite/package.json	Added "code" export fields for framework packages, pointing to root and optional secondary exports (e.g., "./node", "./preview", "./preset") in their respective src directories.
Library Packages code/lib/codemod/package.json, code/lib/core-webpack/package.json, code/lib/csf-plugin/package.json, code/lib/eslint-plugin/package.json, code/lib/react-dom-shim/package.json	Added "code" export field for main export entry in each library package.
Preset Packages code/presets/react-webpack/package.json, code/presets/server-webpack/package.json	Added "code" export field pointing to main source file for each preset.
Renderer Packages code/renderers/html/package.json, code/renderers/preact/package.json, code/renderers/react/package.json, code/renderers/server/package.json, code/renderers/svelte/package.json, code/renderers/vue3/package.json, code/renderers/web-components/package.json	Added "code" export fields for renderer packages, including main exports and framework-specific exports (e.g., "./experimental-playwright", "./preview").
Build Configuration code/tsconfig.json	Added "code" to customConditions compiler option to recognize code exports during TypeScript resolution.
Build Utilities scripts/build/utils/generate-package-json.ts	Updated export map generation to include "code" field pointing to entry.entryPoint when dts is undefined.
Build Script Changes scripts/build/build-package.ts	Removed import and invocation of generateTypesMapperFiles function.
Deleted Build Module scripts/build/utils/generate-type-mappers.ts	Removed entire module containing generateTypesMapperContent and generateTypesMapperFiles functions that were used for type mapper generation.
TypeScript Source Fix code/core/src/types/modules/api-stories.ts	Changed StatusByTypeId import from external source to local module import from './status'.

Estimated code review effort

🎯 2 (Simple) | ⏱️ ~12 minutes

Possibly related PRs

• Cleanup: Remove duplicated entrypoints in core #32507 — Adds "code" export fields to package.json files across many packages, directly related to the export infrastructure being modified in this PR
• Addon-Vitest: Support Vitest 4 #32819 — Modifies the same package.json file (code/addons/vitest/package.json) with dependency updates that may conflict with export changes

✨ Finishing touches

• 📝 Generate docstrings

Important

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