prepublish

Prepublish refers to a stage in a publishing workflow during which preparatory tasks are completed before an item is released. In software development and content distribution, prepublish tasks are intended to ensure that artifacts are ready for public use, such as being properly built, tested, and packaged, and that metadata and licenses are correct. The exact steps of prepublish vary by domain but commonly include building distributables, running tests, generating documentation, and bundling assets.

In the npm ecosystem, prepublish was a lifecycle script that ran before the package was published to the npm registry and before npm pack. It was often used to run build or test commands. Because it could execute during ordinary npm install of dependencies, it could surprise downstream users. To address this, npm promoted using prepare for tasks that should run both during development and before publish, and introduced prepublishOnly for tasks that should run only during npm publish.

Best practices in general emphasize limiting prepublish to non-destructive validation and preparation steps, and moving heavy or environment-sensitive operations to CI pipelines or to dedicated scripts invoked by developers during local work. Understanding the target workflow is essential to avoid unintended side effects during installation or distribution.