Context: As documented in #454 and How Microbundle decides which dependencies to bundle, one recommended way to bundle dependencies is to put the dependency in devDependencies rather than dependencies.

Problem: my-bundled-dependency is bundled into my-parent-library, and affects its exported type definitions. Recently a downstream user of my package reported an issue that surprised me – while the JavaScript is bundled as expected, the type definitions are not bundled, and contain an import from my-bundled-dependency. This causes builds to fail for users of my-parent-library if they've enabled TypeScript's skipLibCheck: false. If this is unexpected and a simple repro example would be helpful, I'm happy to create that.

Alternatives: Should the type definitions also be bundled by Microbundle? By TypeScript? Am I perhaps making a mistake by using a bundled dependency in my exported TypeScript API? I'm inclined to the idea that this is something TypeScript, not Microbundle, should ideally handle. But they've historically been pretty unenthusiastic about such requests.

Related:

• Type error if compiled into a project with "skipLibCheck": false donmccurdy/glTF-Transform#996