// Create an Employee
public static IO <EmployeeAgg> CreateEmployeeAndPersist(string firstName, string lastName, string email, string phone, string job, string username, string password, int restaurantId)
=> from employeeCreated in RestaurantDomain.CreateEmployee(firstName, lastName, email, phone, job, username, password, restaurantId)
let agg = (employeeCreated as CreateEmployeeResult.EmployeeCreated)?.Employee
from db in Database.AddOrUpdate(agg.Employee)
select agg;