This depends on the SDK - both Typescript and Golang support a `registerAction` method on the worker which basically let you register a single step to only run

This depends on the SDK - both Typescript and Golang support a `registerAction` method on the worker which basically let you register a single step to only run on that worker. You would then call `putWorkflow` programmatically before starting the worker. Steps are distributed by default so they run on the workers which have registered them. Happy to provide a more concrete example for the language you're using.