sp-dev-fx-webparts/samples/react-yammer-api/.yo-rc.json

{
  "@microsoft/generator-sharepoint": {
    "libraryName": "react-yammer-api",
    "framework": "react",
    "version": "1.0.0",
    "libraryId": "9e199a26-c09f-4071-9902-ee8e40e80f16"
  }
}