![Steve Jobs announcing the Keynote app at MacWorld 2003, joking that it was build for himself, him being an underpaid beta tester](/blog/2020-03-25_designing-and-implementing-a-micro-payment-system/images/i_00_Steve-Jobs-announcing-the-Keynote-app-at-MacWorld-2003-joking-that-it-was-build-for-himself-him-bein_500px.jpg)
![Interface concept sketches, exploring different options to leave a message and buying multiple cups of coffee](/blog/2020-03-25_designing-and-implementing-a-micro-payment-system/images/i_01_Interface-concept-sketches-exploring-different-options-to-leave-a-message-and-buying-multiple-cups-o_500px.png)
![Stacking two plastic cards is easy](/blog/2016-07-15_cash-is-king-or-is-it/images/i_01_Stacking-two-plastic-cards-is-easy_500px.jpg)
![Programming on iPad Pro using VIM, Blink and a Linux VPS](/blog/2017-07-31_the-day-i-killed-my-lan/images/i_02_Programming-on-iPad-Pro-using-VIM-Blink-and-a-Linux-VPS_500px.jpg)
![Eating pizza during development is how you](/blog/2020-12-02_designing-a-multi-dimensional-capacity-queue/images/i_00_Eating-pizza-during-development-is-how-you-live-the-algorithm_500px.jpg)
![iPad Pro + Apple Pencil replacing paper](/blog/2017-07-31_the-day-i-killed-my-lan/images/i_01_iPad-Pro-Apple-Pencil-replacing-paper_500px.jpg)
![Designing the coffee cup using Picta Graphic for iPad](/blog/2020-03-25_designing-and-implementing-a-micro-payment-system/images/i_03_Designing-the-coffee-cup-using-Picta-Graphic-for-iPad_500px.jpg)
![Three capacity constraints: kitchen / delivery / pickup](/blog/2020-12-02_designing-a-multi-dimensional-capacity-queue/images/i_01_Three-capacity-constraints-kitchen-delivery-pickup_500px.jpg)
![This case allows easy access to the payment card while hiding the ID inside.](/blog/2016-07-15_cash-is-king-or-is-it/images/i_04_This-case-allows-easy-access-to-the-payment-card-while-hiding-the-ID-inside_500px.jpg)
![An event stream of orders is the heart of the mechanism, queries are fulfilled by looking at this stream: how many pizza's will be ready at 18:00hrs?](/blog/2020-12-02_designing-a-multi-dimensional-capacity-queue/images/i_02_An-event-stream-of-orders-is-the-heart-of-the-mechanism-queries-are-fulfilled-by-looking-at-this-str_500px.jpg)
![Mollie is a payment provider that supports many different payment methods, including credit cards, PayPal, iDEAL, Sofort, Giropay, SEPA, various bank apps and Apple Pay](/blog/2020-03-25_designing-and-implementing-a-micro-payment-system/images/i_06_Mollie-is-a-payment-provider-that-supports-many-different-payment-methods-including-credit-cards-Pay_500px.png)
![Handling payment status updates](/blog/2020-03-25_designing-and-implementing-a-micro-payment-system/images/i_08_Handling-payment-status-updates_500px.jpg)
![The iPhone with case is only slightly thicker.](/blog/2016-07-15_cash-is-king-or-is-it/images/i_02_The-iPhone-with-case-is-only-slightly-thicker_500px.jpg)
![Feeling old already, my trustworthy old local area network (LAN)](/blog/2017-07-31_the-day-i-killed-my-lan/images/i_00_Feeling-old-already-my-trustworthy-old-local-area-network-LAN_500px.jpg)
![Maybe... my next office? ;-)](/blog/2017-07-31_the-day-i-killed-my-lan/images/i_05_Maybe-my-next-office_500px.jpg)
![Just like any other iPhone: but this one has an NFC contactless bank card and ID hidden it it!](/blog/2016-07-15_cash-is-king-or-is-it/images/i_03_Just-like-any-other-iPhone-but-this-one-has-an-NFC-contactless-bank-card-and-ID-hidden-it-it_500px.jpg)
![Sketched sequence diagram of payment process](/blog/2020-03-25_designing-and-implementing-a-micro-payment-system/images/i_05_Sketched-sequence-diagram-of-payment-process_500px.jpg)
![The iPhone case is large enough to hide cards.](/blog/2016-07-15_cash-is-king-or-is-it/images/i_00_The-iPhone-case-is-large-enough-to-hide-cards_500px.jpg)
This month I needed to create additional dimensions to a capacity queue mechanism. The food ordering app that I created needed to be able to restrict capacity based on the number of orders, the contents in individual orders and the dispatch type (takeaway/delivery). Read along to find out how I used a Lambda Architecture to do this.
Online payments are now more important than ever as businesses are disrupted by the COVID-19 virus. It drives my customers to seek new ways to make money online. I designed and implemented a (micro)payment system. This post is about achieving simplicity by solving complex challenges.
Today I called my provider to quit my office's ADSL internet subscription, I don't need it anymore. I have turned off my local area network and switched my workflow onto mobile internet only. The simplicity and savings actually surprised me so much, that I made blog post for it.
Very often I see men carry a wallet filled with plastic: multiple debit and credit cards plus a bunch of loyalty programs and membership cards. Then, some even top it off with stinky paper money and sticky metal coins! It made me wonder if I can free up one pocket by ditching the wallet?