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KMP now generates a 731.js next to my main JS file. The content doesn't seem harmful, but what is this and why is this there?

Is it in `compileSync` build directory or where?

Screenshot 2025-07-29 at 12.38.10.png

What's the content if I may ask? I see those files when bundling with Webpack, not always tho.

This is done via <https://webpack.js.org/configuration/optimization/#optimizationsplitchunks>
Seems like chunks can be <https://github.com/JetBrains/kotlin/blob/f2f9688b28b4778ad35df0166ce801592e6751eb/libraries/tools/kotlin-gradle-plugin/src/common/kotlin/org/jetbrains/kotlin/gradle/targets/js/dsl/KotlinJsTargetDsl.kt#L329|configured> via DSL. Take a look at the generated `webpack.config.js`

I've seen such chunk generated suddenly after adding kotlinx-datetime library to the project (the chunk was js-joda, which is used by the library for JS target).

I feel like WP is just optimizing it as it thinks is the best way based on modules' entry points. But you can just disable the optimization if you don't like it.

Thanks for the answers. I haven't looked into chunks yet, it's good to know that it belongs to that part.

It also can be any lazy module, which you have in your project or in transitive dependencies