Use an injection token to provide your DI enabled reducer function

medium-ngrx-reducer-provider.ts

export const ACCOUNT_REDUCER_TOKEN = new InjectionToken<ActionReducer<Map<string, Account>>>('Account state reducer')

export function accountReducerFactory(accountReducer: AccountReducer): ActionReducer<Map<string, Account>> {
  // here you create a reducer function with access to other managed services
  return accountReducer.createReducer()
}

@NgModule({
  imports: [
    StoreModule.forFeature('account', ACCOUNT_REDUCER_TOKEN)
  ],
  providers: [
    {
      provide: ACCOUNT_REDUCER_TOKEN,
      // here your AccountReducer class will be instantiated with its deps injected
      deps: [AccountReducer],
      useFactory: accountReducerFactory
    }
  ]
})
export class AccountModule {
}