Configurable reducers - https://blog.apiary.io/2018/02/12/Reusable-features-in-React-Redux#comment-3776553185

action.js

// in reusable feature instance

import createActions from '../reusable-feature/actions';
import selectors from './selectors';
import { createAction } from 'redux-actions';


const actions = createActions('INSTANCE_1', selectors);

actions['additionalAction'] = createAction(...);
                                           
export default actions;                                           

reducers.js

// in reusable feature template

import { handleActions } from 'redux-actions';


export default function createReducers(actions) {
  const initialState = {
    clickCount: 0,
  };

  const handlers = {
    [actions.incrementClick]: state => ({ ...state, clickCount: state.clickCount + 1 }),
  };
  
  if (action.additionalAction) {
    handlers[actions.additionalAction] = state => ({ ... });
  }

  return handleActions(handlers, initialState);
};