`declaration` inside `entries` have no effect

[NamesMT]

Environment

---

• Operating System: Linux
• Node Version: v22.14.0
• Package Manager: pnpm@10.8.0
• Unbuild Version: v3.5.0

---

Reproduction

Any simple dummmy repo with the config:

export default defineBuildConfig({
  entries: [
    // Main engine
    {
      input: 'src/index',
      declaration: 'node16',
    },

    // CLI app
    {
      input: 'src/cli',
      declaration: false,
    },
  ],
  declaration: false,
  clean: true,
  rollup: {
    inlineDependencies: true,
    esbuild: {
      target: 'esnext',
      // minify: true,
    },
  },
})

Describe the bug

declaration inside entries have no effect, no declaration files is generated with the included config.

Additional context

No response

Logs

[kricsleo]

The declaration in entries doesn't take effect. You shouldn’t define it per entry—only the top-level declaration is respected.
In other words, you currently can’t generate dts for one entry but not others.

To resolve this, we have two options:

• Remove declaration from RollupBuildEntry types to prevent confusion (simpler solution).

Or:

• Support per-entry declaration, though this is more complex due to varying values ("compatible" | "node16" | boolean) across entries.

WDYT? 🤔 @pi0

[pi0]

per entry for rollup does not works, unbuild does single build phase for all rollup because it can share chunks (it is by design).

fixing types to omit makes more sense.

[kricsleo]

@NamesMT unbuild does not support generating dts for a single entry while excluding others.
However, if you insist on this approach, you can try separating them into multiple configs (though it may seem verbose).

For example:

import { defineBuildConfig } from 'unbuild'

export default defineBuildConfig([
  {
    // Main engine
    entries: ['src/index'],
    declaration: 'node16',
    clean: true,
    rollup: {
      inlineDependencies: true,
      esbuild: {
        target: 'esnext',
        // minify: true,
      },
    },
  }, {
    // CLI app
    entries: ['src/cli'],
    declaration: false,
    clean: true,
    rollup: {
      inlineDependencies: true,
      esbuild: {
        target: 'esnext',
        // minify: true,
      },
    },
  }
])

[NamesMT]

Yup I see, just raising an issue to see what the maintainers think about it, omitting the declaration prop seems good to me.

Letting it use the same build config allows them to share chunks which is way better and cleaner than splitting to two configs 👍, there's no real drawback to just let it generate an empty dts for cli.ts.

Thanks!