Delhi to London : What it’s like to be relocated for a new job!

Since I am from India, I always think in terms of Bollywood movies, where everything is possible. Yes, that’s right…everything. Maybe that is why when I started off with Badoo, I always believed that this was within my reach. If I were to make a Bollywood movie of my journey…

Fixing serialization of Kotlin objects once and for all

Some time ago, I read an article describing a problem experienced with Kotlin objects and serialization using built-in Java methods. The author suggests an amazing solution involving adding the readResolve method to each object implementing java.io.Serializable rather than using instance checks. Despite this approach seemingly being the most correct one…

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…

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…

Introduction of View Styles at Bumble

We are the team behind Badoo and Bumble, two of the world’s largest dating and connection applications with millions of users worldwide. To deal with the challenges that arise with such different products we rely on code reusability, and by so avoiding reinventing the wheel we keep our apps stable…

What Google I/O 2019 addressed: Android 10, AR-applications and much more

In this article I’ll share my thoughts on Google I/O 2019 that my colleagues and I attended recently (and Badoo were even mentioned in one of the talks). During the three days, there were more than 150 talks, lots of choice as you can see, but I really wanted to…

Walk or talk at the best QA conferences in 2018

Do you like meeting new people, sharing your knowledge and keeping up-to-date with the latest technology trends? Then you should definitely check your calendar and add there a few upcoming testing events. I started visiting conferences and meetups a few years ago when I was studying at the university. They…

Part 1: Deep Learning for Engineers

Introduction Deep learning has become one of the most discussed topics in the Data Science community. It has long made sense for the Bumble team — the parent company operating Badoo and Bumble apps — to use deep learning on a multitude of tasks. With over millions of users around the…

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…

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…

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…

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…

Deep Neural Networks & Image Captioning

Part 2: Using attention networks to improve the quality of image captions In my previous blog, I introduced the concept of combining a CNN with an LSTM to generate a caption of an image, and talked about how we are using this at Badoo to help our users find love. This time, we will explore how the incorporation of attention networks can…

Optical alignment for frontend developers:

How to align elements in user interfaces. Hi, my name is Ivan Grekov and I work in the front-end team at Badoo. My primary responsibilities entail looking after the user interfaces for a variety of projects. More specifically, this involves working with optical alignment of user interfaces. In this article, I’d like to share with you why…

Aspiring team lead?

Six tips on how to meet deadlines and develop your team When I became a team lead for the first time, I started going to lots of conferences and reading deep books on team management. I was reading all about what I should be and how I should develop, but it was still not clear to me what exactly I should…

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…

A Custom LayoutManager Case: Bumble Beeline

Task

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…

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…

Scalable Jetpack Compose Navigation

Introduction For one of my recent personal projects, I decided to make Jetpack Compose a first-class citizen. For me, this meant that my app would use a single activity, and all the navigation would be performed using Compose. When I originally started investigating the feasibility of this, Jetpack Compose Navigation did…

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…

iOS UI development in Badoo

Hey! Being a developer in Badoo is not only interesting and fun, but also challenging — you have to produce highly maintainable code in a short period of time. Due to the amount of new features coming to our team on a weekly basis, we have to think of the…

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…

Client-side neural networks

Historical background The popularity of machine learning and neural networks is growing every day, and faster than we could ever have imagined. Many industry players are contributing, and client-side frameworks are developing rapidly. Many libraries, such as TensorFlow, are constantly releasing new versions. More mobile devices are now receiving hardware support for…

Part 2: Dynamic Delivery in multi-module projects at Bumble

In part 1 of my series of articles, I have already explained to you what Dynamic Delivery is and what API it has. In this article, I describe in detail exactly how I used Dynamic Delivery in our application Bumble and why, in particular, integration was so easy. As a…