1. The document compares Paymill and Stripe payment processing services. It details the author's experience using each platform and identifies some issues they encountered with Paymill. 2. While Paymill and Stripe work similarly, the author decided to switch to Stripe due to a number of small problems with Paymill that added up, including unsupported cards, errors not being addressed, and difficulties testing transactions. 3. Both platforms have similar features for accepting payments online or via mobile apps. However, the author concludes Stripe has better customer focus and slightly lower costs, making it the better overall choice compared to Paymill.

1. Paymill or Stripe?
Betabeers Madrid 44
Ivan Maeder
Coderswitch
@ivanmaeder

2. My experience

3. 1 price point (non-
recurring)
June 2013
Multiple price points
(recurring and non-
recurring)
March 2014
$199 $199$99/month$49/month

4. What are Paymill and Stripe?

7. if (paymill == stripe)
printf("They work the same way");
else
printf("They work the same way");

8. Then why did you change?

10. Lots of little things that add up

11. Not all cards available to us
Cards supported > cards supported in our account
Test OK, live FAIL
Out of date documentation? No help for four days
Error in API
Error case, probably ignored by most people
Unable to debug error
Called the bank directly
Difficult to test transactions live
Blacklisted cards
Name shown on card statements
Martin Cabrera → Marsin Gabrera Diatb → Codekai
PCI documentation
Endlosschleife

12. Shut up and code

13. 1. Register online
2. Download API (back-end)
3. Get token via JavaScript (Ajax)
4. Take payment (back-end)

14. 1. Register online
2. Download API (back-end)
3. Get token via JavaScript (Ajax)
4. Take payment (back-end)

15. Paymill Stripe
C# ✔ Community
Go ✘ Community
Java ✔ ✔
Node.js ✔ ✔
Perl ✘ Community
PHP ✔ ✔
Python ✔ ✔
Ruby ✔ ✔

16. Paymill Stripe
Android ✔ ✔
iOS ✔ ✔

17. 1. Register online
2. Download API (back-end)
3. Get token via JavaScript (Ajax)
4. Take payment (back-end)

18. Paymill

19. <form>
<input name="card-number">
<input name="card-expiry">
<input name="card-security-code">
</form>

20. <form>
<input name="card-number">
<input name="card-expiry">
<input name="card-security-code">
</form>

21. <form>
<input class="card-number">
<input class="card-expiry">
<input class="card-security-code">
</form>

22. <form>
<input type="hidden" name="token">
<input class="card-number">
<input class="card-expiry">
<input class="card-security-code">
</form>

23. <script>
var PAYMILL_PUBLIC_KEY = "<$= publicKey() ?>";
</script>
<script src="https://bridge.paymill.com/"></script>

24. $('form').submit(function() {
...
if (paymill.validateCardNumber(cardNumber)) {
...
paymill.createToken({
"number": cardNumber,
...
"amount_int": 19900,
"currency": EUR
}, paymillResponseHandler);
return false;
});

26. function paymillResponseHandler(error, result) {
if (error) {
...
}
else {
$('input[name="token"]').val(result.token);
}
$('form').submit();
}

27. That was Paymill

28. That was Paymill
This is Sparta Stripe

29. <script src="https://js.stripe.com/v2/"></script>
<script>
Stripe.setPublishableKey("<$= publicKey() ?>");
</script>

30. <form>
<input type="hidden" name="token">
<input class="card-number">
<input class="card-expiry">
<input class="card-security-code">
</form>

31. <form>
<input type="hidden" name="token">
<input data-stripe="number">
<input data-stripe="exp-month">
<input data-stripe="exp-year">
<input data-stripe="cvc">
</form>

32. $('form').submit(function() {
...
if (Stripe.card.validateCardNumber(cardNumber)) {
...
Stripe.card.createToken($('form'), stripeResponseHandler);
return false;
});

34. function stripeResponseHandler(statusCode, response) {
if (statusCode != 200) {
...
}
else {
$('input[name="token"]').val(response.id);
}
$('form').submit();
}

35. 1. Register online
2. Download API (back-end)
3. Get token via JavaScript (Ajax)
4. Take payment (back-end)

36. Paymill (PHP)

37. $obj = new Services_Paymill_Transactions(privateKey(),
"https://api.paymill.com/v2/");
$transaction = $obj->create(array("amount" => 19900,
"currency" => 'EUR',
"token" => $token
));
if ($transaction["response_code"] != 20000) {
...
}

38. Stripe (PHP)

39. Stripe::setApiKey(secretKey());
try {
$charge = Stripe_Charge::create(array(
"amount" => 19900,
"currency" => "eur",
"card" => $token
));
} catch (Stripe_CardError $e) {
...
}

40. 1. Register online
2. Download API (back-end)
3. Get token via JavaScript (Ajax)
4. Take payment (back-end)

41. $
$

42. Testing

43. Recurring payments

44. $customer = Stripe_Customer::create(array(
"card" => $token
));
$customer->subscriptions->create(array(
"plan" => "MY_PLAN_1"
));

45. Changing subscriptions

46. $customer = Stripe_Customer::retrieve($stripe_customer_id);
$subscription = $customer->subscriptions->retrieve($stripe_subscription_id);
$subscription->plan = "MY_PLAN_2";
$subscription->save();
$invoice = Stripe_Invoice::create(array(
"customer" => $stripe_customer_id
));
$invoice->pay();

47. -$0 -$200
-$50
-$100
1 2 3 4 5 6 7
8 9 10 11 12 13 14
15 16 17 18 19 20 21
22 23 24 25 26 27 28
29 30
1 2 3 4 5
6 7 8 9 10 11 12
13 14 15 16 17 18 19
20 21 22 23 24 25 26
27 28 29 30 31
-$100
$200$100/month
/month $200/month

48. $customer = Stripe_Customer::retrieve($stripe_customer_id);
$subscription = $customer->subscriptions->retrieve($stripe_subscription_id);
$subscription->plan = "MY_PLAN_2";
$subscription->save();
$invoice = Stripe_Invoice::create(array(
"customer" => $stripe_customer_id
));
$invoice->pay();

49. $200$100
-$200
1 2 3 4 5 6 7
8 9 10 11 12 13 14
15 16 17 18 19 20 21
22 23 24 25 26 27 28
29 30
/month
/month
1 2 3 4 5
6 7 8 9 10 11 12
13 14 15 16 17 18 19
20 21 22 23 24 25 26
27 28 29 30 31
-$100 -$50
-$100
$200/month

50. Costs

51. 0.28€ + 2.95%
per transaction
+2% for currency exchange
$0.30 + 2.9%
per transaction
No additional exchange
rate costs for European
currencies

52. Paymill Stripe
10€ 0.575€ 0.510€
100€ 3.230€ 3.120€
200€ 6.180€ 6.020€
500€ 15.030€ 14.720€

53. Refunds cost zero

54. Accepted cards

55. Paymill Stripe
Visa ✔ ✔
MasterCard ✔ ✔
American Express ✔ ✔
Diners Club ✔ ✘
Discovery ✔ ✘
China Union Pay ✔ ✘
JCB ✔ ✘

56. Paymill Stripe
Visa Electron ✔ ✘
Visa Debit ✔ ✘
Maestro ✔ ✘
MasterCard Debit ✔ ✘

57. And the winner is…

58. Paymill Stripe
Features ✔✔ ✔✔
Cards available ✔✔ ✔✔
Price ✔✔ ✔✔
Customer focus ✔✘ ✔✔
Programmability ✔✔ ✔✔

59. Keep in mind

60. 30% more test cases
Validations, error-handling
Data model
Minimum: customers, products, orders
Design
Payment form, A/B test conversion, email design and copy, convey confidence
Terms of use
Money back guarantee, trial periods or free plans, how to handle returns
Pricing
Good references: “Don’t Just Roll the Dice” and “Camels and Rubber Duckies”
Administration screens
For customers to view payments and download invoices, change cards
Other stuff
Taxes, phone support

61. Questions?

62. Thank you!

63. Ivan Maeder
Coderswitch
@ivanmaeder