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…

Generating multi-brand multi-platform icons with Sketch and a Node.js script

TL;DR Using a custom build script in Node JS, it is possible to manipulate a series of Sketch files, and then, using an internal Sketch tool, automatically export their assets, to generate multiple icon libraries, for multiple platforms and different brands, that support dynamic colourisation of the assets via design tokens…

Reaktive binary compatibility: how we achieve it

As part of the Bumble family — the parent company operating Badoo and Bumble apps — one of my main projects was involved in the team that created Reaktive library — reactive extensions on pure Kotlin. Whenever possible, any library must maintain binary compatibility. Whenever various versions of a library…

MVI beyond state reducers

This is the first part in a series of articles on Android architecture in Badoo. You can find the next one here: Part II — Building a system of reactive components with Kotlin Story time: problems of state Your application has a state at any given time that determines its behaviour and what the user…

Optimising relational databases with zero downtime

A case study of Badoo’s most loaded database Optimising relational databases is much harder in high-load circumstances: buying an even more powerful hardware is expensive, and one cannot just turn off the app at night to alter the database and migrate data. In this article I would like to tell you how we completely changed the inner structure…

Image detection as a service

How we use deep learning and APIs to support our products Across our two apps Badoo and Bumble, we have over millions registered users worldwide uploading millions of photos a day to our platform. These images provide us with a rich data set from which we derive a wealth of insights.

Features, but faster: the life of an Android developer at Badoo

Practically speaking, my colleagues and I often need to test an idea as fast and as simply as possible. There’s no point spending lots of effort on implementation because we know that if an experiment proves unsuccessful, we are going to jettison the code in question. Here I will be…

How to use Composite builds as a replacement of buildSrc in Gradle

Gradle buildSrc approach has become standard for implementing custom plugins, tasks and specifying common configurations (like dependencies list and versions) but has one major flaw — it invalidates a build cache when it is changed. On the other hand, Gradle also provides an alternative composite build approach that lacks this…

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…

Part 1: Dynamic Delivery in multi-module projects at Bumble

Dynamic Delivery is a technology which allows you to install and delete parts of an application while the application is working, in order to reduce the space it occupied. If there are functions not being used, what is the point of a user having them on their device? In part…

Overview of KotlinConf 2019

I’ve been developing with Kotlin for the past two years, and when I was asked if I’d like to attend KotlinConf 2019 with some of my colleagues, my answer was a great, big Y-E-S! Having the chance to attend what is one of the best conferences for mobile devs, I…

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…

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.

Swift Package Manager builds iOS frameworks (Updated. Xcode 10.2 Beta)

(Updated. Xcode 10.2 Beta) Swift Package Manager doesn’t work with iOS. That’s probably all you can say about the current state of SPM, but insomnia forced me to expand on the issue and compile the following essay. TL;DR Yes, you can build iOS frameworks with Swift Package Manager; Yes, you can adjust settings via .xcconfig…

Working with a cache: problems and solutions

Hello all! My name is Victor Pryazhnikov and I’m part of the server team at Badoo. Our team is developing and supporting internal API for our customers server-side, caching data is something we deal with every day. Here’s an interesting opinion when it comes to programming: “There are only two…

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…

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…

The secret to great code reviews

Nowadays, lots of people in development use code review recognising it as both helpful and useful. Even if you don’t perform review you probably know what it is. There are loads of code review tools available on the market, complete with use scenarios, recommendations and rules, such as: GitHub, Phabricator…

Configuring Jira for your needs

Perfect flow and ideal ticket If you work in an IT company then the likelihood is that your processes are built around Atlassian’s well-known Jira. There are numerous task-trackers available on the market for solving such tasks, including open-source solutions (Trac, Redmine, Bugzilla), but Jira is probably the most widely used. My name is Dmitry…

How we achieved a 6x reduction of ANRs. Part 1: Collecting Data

One of the worst things that can happen to your app’s responsiveness is an Application Not Responding (ANR) dialogue. A high ANR rate may affect user experience and, potentially, Google Play search positions and featuring. At the beginning of the year, we had ANR rate above the Google Play threshold…

Crowdtesting

source: pinterest.co.uk It’s been a while since I first heard about crowdsourced testing platforms. It was a time when I had just started to be interested in QA, and when I was browsing Google one day, I found a forum, where a link to the site uTest.com was posted. After a brief…

Particle systems: a Christmas story

Christmas has always been one of my favourite times of the year. For me, Christmas is a season that brings so much love, laughter, happiness, and other magical things into our lives. I was born and raised in Spain, more specifically in Tenerife, a sunny subtropical island in the middle…

Bitmap indexes in Go: unbelievable search speed

Foreword My name is Marko and I gave a talk at Gophercon Russia this year about a very interesting kind of indexes called “bitmap indexes”. I wanted to share it with the community, not only in video format, but as an article too. Please enjoy! Additional materials, slides and all…

Modularising the Badoo iOS app

In my previous article, I explained how we singled out the chat functionality in our app for modularisation. Everything had gone well and we were preparing to roll out this experience to start work on modularising all of Badoo iOS app development. We even did a presentation on the approach…

How to move large-scale React UI-components codebase to TypeScript

Hi, my name is Ivan Grekov and I am a frontend developer at Bumble — the parent company operating Badoo and Bumble apps Our frontend team’s main responsibilities are to deliver new user interfaces and support existing ones across our different applications, mostly within Badoo and Bumble websites. At a…