Consider about ImmerReducer

[Brooooooklyn]

Using immer in complicated state is much more concise than POJ.
For example:

interface State: {
  ui: {
    comments: { [index: string]: Array<Comment> }
  }
}

@ImmerReducer()
addComment(state: State, { payload }: Action<{ articleId: string, comment: Comment }>) {
  state.ui.comments[payload.articleId].push(payload.comment)
}

vs

@Reducer()
addComment(state: State, { payload }: Action<{ articleId: string, comment: Comment }>) {
  const comments = state.ui.comments.get(payload.article)
  return { ...state, ui: { ...state.ui, comments: { ...state.ui.comments, [payload.articleId]: [...comments, payload.comment] } } }
}