method

PluginBuilder.onStart

callback: OnStartCallback
): this;

Register a callback that runs when bundling starts. With hot module reloading, it runs at the start of each incremental rebuild.

@returns

this for method chaining

Bun.plugin({
  setup(builder) {
    builder.onStart(() => {
      console.log("bundle just started!!")
    });
  },
});

Referenced types

type OnStartCallback = () => void | Promise<void>