BPF and Go: Modern forms of introspection in Linux

Everyone has their favourite book about magic. For one person it is Tolkien, for another Pratchett, for a third, like me, it is Max Frei. Today I am going to tell you about my favourite IT magic: BPF and the modern infrastructure surrounding it. BPF is currently at the height…

Implementing UI in iOS: Better, faster, and it scales!

A few months ago I came across a very interesting documentary series on Netflix called Abstract, they basically explore the output of professional designers from different sectors like architecture, graphic design, fashion, … in their workplaces. It was easy to spot some similarities in the work of designers from…

Run, config, run: How we speed up config deploy

Configuration files (configs) are an integral part of most applications, but practice shows that they are far from being the most popular topic of discussion. Conversations about configs are mostly limited to discussing working with them directly in the code: how to structure them, whether or not using environmental variables…

Modularising an iOS app

At Bumble — the parent company operating Badoo and Bumble apps — the iOS development team have been involved in creating modules for several years now. A large part of the new code is also being developed outside the apps’ code base. As a result of this work, we now…

A Custom LayoutManager Case: Bumble Beeline

Task

Using Hopper to investigate an IOS bug

In this article, I share how we investigated a bug in UIKit, which Apple wasn’t able to solve since the introduction of a new major iOS version until the recent release of iOS 13.4.1. The problem was first noticed in August 2019 with the first beta versions of iOS13. In…

Design Tokens beyond colors, typography, and spacing.

In recent months, I couldn’t help but notice how many people (and companies) when referring to “design tokens” what they actually mean is colors, typography, spacing (and in some cases elevation, timing, and sizing). While this is perfectly true, I think a key part of the picture is missing: design…

Reactive selfies with Camera2 API on Android — Part 2

This is part two of an article, where I show how you can use RxJava2 to build logic on top of asynchronous API. I chose Android Camera2 API as an example (and didn’t regret it!). This API is not only asynchronous, but also has hidden distinctive implementation features which are…

Dub-dub 2019: my take on what’s new at WWDC

In this article I share my impressions of the conference: scroll down for, not just read about important updates and an overview of the sessions, but also something on my own personal feelings, having spent time with a happy crowd of people chanting, “Dub-dub! DC!” and dreaming of shaking Tim…

The story of the lost commit: how to solve this mystery

It was already evening by the time the developer contacted me. The deadbeef commit patch had disappeared from the master branch. They showed me the evidence: the output from two commands. The first one was: git show deadbeef This showed changes to the file: let’s call it Page.php. The canBeEdited…

MVI in Kotlin Multiplatform — part 3 (3 of 3)

This is the concluding article in a series of three articles on MVI architectural pattern in Kotlin Multiplatform. In the previous two articles (part 1 and part 2) we reminded ourselves what MVI is, created the Kittens module for loading images of kittens, and integrated it into iOS and Android…

Making custom designable UI components

Hi there! I’m Valera, iOS Padawan at Badoo. Here in our company we are crazy about UI and spend plenty of time designing, polishing and improving the user interface to make our users happy, not only about the services we provide, but also about the look and feel of the…

Regex bytecode interpreter: looking for needles in session haystacks

Here at Badoo, 17 billion events, millions of user sessions and a huge number of virtual dates take place every day. Each event is carefully anonymised and stored in relational databases for subsequent analysis using SQL and SQL-like languages. Contemporary distributed databases containing dozens of terabytes of data are a…

Volcanic piglet, or do-it-yourself SQL

Collecting, storing and transforming data — these are the main tasks of a data engineer. In any one 24-hour period, Bumble Business Intelligence unit receives and processes over 30 billion events sent from clients’ devices or application servers. Researching and interpreting all this data are not trivial tasks; sometimes it…

Translating Dust templates to JSX

It appeared in the middle of the decade (plagued by the endless JavaScript framework wars), embraced the DOM, shocked everyone by mixing HTML with JavaScript and transformed the web development landscape beyond recognition. All those accomplishments, without even being a framework. Love it or hate it, React…

Liveprof will show you how and why the performance of your PHP app changes over time

App performance is one of the key criteria for evaluating developers’ work. Profiler is a tool used for optimising the performance of PHP apps in particular. If you’re seeing an increased response time but you’re not sure which parts of the code are causing it, you can use XHProf to…

Reaktive — a multiplatform library for reactive Kotlin

Reactive programming is really popular today not least because it has loads of plus points: the absence of what is called ‘callback hell’; a built-in mechanism for processing errors; and a functional programming style that reduces the likelihood of bugs occurring. It makes it much easier to write multi-threaded code…

How many people does it take to change a light bulb?

aka API-Centric Development in Non-API Company (Based on a talk by Konstantin Yakushev @ Nordics APIs) The answer is 24, one to hold the light bulb and … Okay, it’s a bad joke, but the number is right and I’ll explain it why later. Today’s topic is how we ended up developing an API-Centric Development environment…

Guide to mobile app autotesting tools

… for though it has many omissions and contains much that is apocryphal, or at least wildly inaccurate, it scores over the older, more pedestrian work in two important respects. First, it’s slightly cheaper; and secondly it has the words DON’T PANIC printed in large friendly letters on its cover. —…

Data classes in Kotlin: how do they impact an application size

Kotlin has numerous excellent features: null safety, smart casts, string interpolation and more. However, one of its features developers love the most, I have observed, are data classes. They are so well-loved that they are often used where no data class functionality is required. In this article, with the help…

The Immense Benefits Of Not Thinking In Screens

DroidconUK 2019 Lightning Talk Abstract of the talk: Maintaining a large project and not going insane — in practice: – Causes of everyday development pain, frustration and slowdown less frequently talked about – Breaking down the complexity of screens instead of a classical layering approach – Keeping code easy-to-understand…

From zero to Cosmos — Part #1

This is the story of how a small style guide that was first introduced under the radar, became so appreciated by both developers and designers that it eventually became a complex unification project — a design system called Cosmos. As some of you may know, every good story follows a…

How 3 Process Patterns will change the way you do Test Automation

A few years ago, here at Bumble — the parent company that operates Badoo and Bumble apps — we started to shift towards using autotests more in our development, testing and release processes. We have, however, encountered a few challenges along the way. Before we start, you might be curious…

Covering A/B tests with UI tests:

How to avoid getting tangled up in your own code Hi there! My name is Vitaliy Kotov and I spend most of my time working on automated testing issues at Badoo. In this article, I tell you all about how we have organised the UI testing work with our numerous A/B tests, the problems we have had to deal with…

Achieving State Of The Art Results In Natural Language Processing:

Part 1: Fundamental Concepts Badoo is the largest dating network in the world, with over millions of registered users worldwide. Users of our site are prompted to write an “About me” section in order to give any prospective love interests a little bit more information about themselves.