redux-first-router/dist/action-creators/addRoutes.js.flow

think of your app in states not routes (and, yes, while keeping the address bar in sync)

// @flow

import { ADD_ROUTES } from '../index'
import type { RoutesMap, Dispatch } from '../flow-types'

export default (routes: RoutesMap) => (dispatch: Dispatch) =>
  dispatch({ type: ADD_ROUTES, payload: { routes } })