Document esmOnly option for the TypeScript SDK generator - #6942
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Document esmOnly option for the TypeScript SDK generator#6942devin-ai-integration[bot] wants to merge 1 commit into
esmOnly option for the TypeScript SDK generator#6942devin-ai-integration[bot] wants to merge 1 commit into
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| <ParamField path="esmOnly" type="boolean" default="false" toc={true}> | ||
| Ships only the ECMAScript module (ESM) build of the generated package. By default, the generator publishes both CommonJS and ESM builds, which exposes consumers to the [dual package hazard](https://github.com/GeoffreyBooth/dual-package-hazard). When enabled, `package.json` sets `"type": "module"`, `main`, `module`, and `types` point at `./dist/esm/index.mjs` and `./dist/esm/index.d.mts`, the `exports` map (including subpackage exports) has no `require` conditions, and no `tsconfig.cjs.json` or `build:cjs` script is generated. |
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📝 [vale] <FernStyles.Acronyms> reported by reviewdog 🐶
'ESM' has no definition.
| </ParamField> | ||
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| <ParamField path="esmOnly" type="boolean" default="false" toc={true}> | ||
| Ships only the ECMAScript module (ESM) build of the generated package. By default, the generator publishes both CommonJS and ESM builds, which exposes consumers to the [dual package hazard](https://github.com/GeoffreyBooth/dual-package-hazard). When enabled, `package.json` sets `"type": "module"`, `main`, `module`, and `types` point at `./dist/esm/index.mjs` and `./dist/esm/index.d.mts`, the `exports` map (including subpackage exports) has no `require` conditions, and no `tsconfig.cjs.json` or `build:cjs` script is generated. |
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📝 [vale] <FernStyles.Acronyms> reported by reviewdog 🐶
'ESM' has no definition.
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🌿 Preview your docs: https://fern-preview-devin-1789319077-ts-esm-only.docs.buildwithfern.com/learn Here are the markdown pages you've updated: |
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Summary
The TypeScript SDK generator gained an opt-in
esmOnlyconfig option that makes the generated package ship only an ESM build instead of the default dual CommonJS + ESM output. This matters for customers whose consumers are ESM-only: it avoids the dual package hazard (two copies of the same module loaded viarequireandimport) and yields a smaller, single-format package. Default behavior is unchanged when the flag is omitted.Implements docs for: feat(typescript): add opt-in esmOnly flag for ESM-only SDK output (fern-api/fern#17503) — fern-api/fern#17503
Details
fern/products/sdks/generators/typescript/configuration.mdx: new<ParamField path="esmOnly" type="boolean" default="false">entry, placed alphabetically betweenenableInlineTypesandextraDependencies. Covers thepackage.json/exports/ build-script effects, the dual package hazard motivation, the incompatibility withuseLegacyExports: trueandbundle: true, and agenerators.ymlexample. The page has nooutputEsmentry, so no contrast was added.Vale: the only remaining findings in the new block are
FernStyles.Acronymssuggestions forESM, which is defined on first use.fern check --warningspasses with 0 errors.Link to Devin session: https://app.devin.ai/sessions/9854c806214d470da26ea53336829309
Open in Devin Desktop: https://app.devin.ai/desktop/session/9854c806214d470da26ea53336829309?variant=devin