🚀🔔Beginners guide to Web Push Notifications using Service Workers

Push notifications are very common in the native mobile application platforms like Android & iOS. The are most effective ways to re-engage users to your apps. In this post we will look at how to implement push…

Functional views

There are many approaches to try out when creating iOS views! Let’s explore an…

How we do machine learning at iZettle

Three factors that enable a small team to efficiently ship…

API Design — Deriving Signal

In this article, we will explore three abstractions that are useful building blocks in asynchronous event handling. As a use case, we will build an API for registering callbacks to get notified of events. Working with callbacks might sound trivial at first. After all, it is just…

Introducing Flow — Asynchronous programming made easy

Today we are proud to announce the open sourcing of Flow, a Swift framework for building and maintaining complex asynchronous flows. Flow is modern, lightweight and composable, allowing you to write code that is more robust and easier to…

Tidy up Dropwizard and JDBI with Kotlin

Near the end of 2017, some developers at iZettle got together and started discussing the possibility of enterprise development with Kotlin. My team was starting up a new project and we all thought it would be a good opportunity to try our hands at Kotlin.

API Design — Deriving Future

In this article, we will explain what asynchronous operations are, why they are useful, and how their APIs are typically designed. Specifically, we will look at an API for performing network requests. Step by step, we will improve this API, first by introducing the Result<T>…

Hack Weeks at iZettle

When I am doing research on a company I want to work at, one of the things I look for is their approach towards employee motivation and training/education. For me, it is more important to have a proper educational plan than a slight increase on my base salary.

Introducing Presentation — Formalizing presentations from model to result

View controllers play a central role when building iOS applications. However, building, managing and presenting view controllers is not always straightforward. There are many questions that need to be…

API Design — Deriving Lift

There have been many attempts to build Swift libraries for both parsing and generating JSON. The reason is probably that there is no obvious Swift solution and JSON parsing is something most developers have to frequently confront. Swift 4 introduced Codable with the promise to…