Naive implementation of Redux pattern in RxJS

index.ts

import { OpaqueToken } from '@angular/core';
import { Subject } from 'rxjs/Subject';
import 'rxjs/add/operator/do';
import 'rxjs/add/operator/scan';
import 'rxjs/add/operator/observeOn';
import { queue } from 'rxjs/scheduler/queue';
import { ReplaySubject } from 'rxjs/ReplaySubject';

export interface Action {
  type: string;
  payload?: any;
  meta?: {
    [key: string]: any
  };
}

export interface ActionReducer<T> {
  (state: T, action: Action): T;
}

function stateFactory<T>(
  dispatcher$: Subject<Action>,
  reducer: ActionReducer<T>,
  initialState?: T) {

  const state = reducer(initialState, { type: '@@INIT' });
  const state$ = new ReplaySubject(1);
  dispatcher$
    .observeOn(queue)
    .scan(reducer, state)
    .startWith(state)
    .subscribe(state$);
  return state$;
}

export const state = new OpaqueToken('state');
export const dispatcher = new OpaqueToken('dispatcher');

export function provideStore<TState>(reducer, initialState?: TState) {
  return [
    {
      provide: state,
      useFactory: d => stateFactory(d, reducer, initialState),
      deps: [dispatcher]
    },
    {
      provide: dispatcher,
      useValue: new Subject<Action>()
    }
  ];
}