[HttpPost]
public HttpResponseMessage CreateCustomer(string name, string billingInfo)
{
    Result<CustomerName> customerNameResult = CustomerName.Create(name);
    if (customerNameResult.Failure)
    {
        _logger.Log(customerNameResult.Error);
        return Error(customerNameResult.Error);
    }
 
    Result<BillingInfo> billingInfoResult = BillingInfo.Create(billingInfo);
    if (billingInfoResult.Failure)
    {
        _logger.Log(billingInfoResult.Error);
        return Error(billingInfoResult.Error);
    }
 
    Customer customer = new Customer(customerNameResult.Value);
 
    try
    {
        _repository.Save(customer);
    }
    catch (SqlException)
    {
        _logger.Log(“Unable to connect to database”);
        return Error(“Unable to connect to database”);
    }
 
    _paymentGateway.ChargeCommission(billingInfoResult.Value);
 
    _emailSender.SendGreetings(customerNameResult.Value);
 
    return new HttpResponseMessage(HttpStatusCode.OK);
}

[HttpPost]
public HttpResponseMessage CreateCustomer(string name, string billingInfo)
{
    var customerName = CustomerName.Create(name); 
    var billingInfo = BillingInfo.Create(billingInfo);
    var customer = new Customer(customerName);
    _repository.Save(customer);
    _paymentGateway.ChargeCommission(billingInfo);
    _emailSender.SendGreetings(customerName);
    return new HttpResponseMessage(HttpStatusCode.OK);
}

.OnSuccess(
            customer => _repository.Save(customer)
                .OnFailure(() => _paymentGateway.RollbackLastTransaction())
        )

Result<BillingInfo> billingInfoResult = BillingInfo.Create(billingInfo);
Result<CustomerName> customerNameResult = CustomerName.Create(name);