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…

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.

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…

Catching bugs on a client

Our team develops several products, Badoo and Bumble, two of the world’s largest dating and connection applications. For both, we have a web version (desktop and mobile) and mobile applications (Android and iOS). With more than millions of users, it’s important for us to gather client-side errors, and for this…

Singleton, Service Locator and tests in iOS

In this article, I want to review the usage of Singleton and Service Locator patterns in iOS and the reasons why they are often called anti-patterns. We’ll learn when and how to use them, while keeping our code testable. Singleton Singleton is a class which has only one instance existing at…

Intercepting and redefining modal presentation from a third-party framework

The Problem Some time ago, here at Badoo, we introduced a third-party library to cover our project needs. It was working well, except for one detail: it was presenting UI using iOS modal presentation (typical full screen view controller which is shown from the bottom of the screen), but according to our…

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…

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…

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…

Cron in Linux: history, use and structure

There is an age-old classical saying that happy people don’t watch the clock. There weren’t any programmers or Unix operating systems in those pre-civilisation times, but in our day programmers know for sure that cron is watching the clock for them. For me, command-line utilities are both a passion and…

Mutation Testing in PHP: quality measurement for code coverage

How do you evaluate how good your tests are? Many people rely on the most popular score, the one everyone knows — code coverage. But this is a quantitative, rather than a qualitative metric. It shows how much of your code is covered by the tests, but not how well…

Deep Neural Networks & Image Captioning

Part 1: Helping our users find love on Badoo Badoo is the largest dating network in the world, with over millions users across 190 countries who upload over 10 million photos per day to our platform. These images provide us with a rich data set we can derive a wealth of insights from. Our Data Science team use image…

Writing Kotlin Parcelize compiler plugin for iOS

This article describes my experience writing a Kotlin compiler plugin. My primary goal was to create a Kotlin compiler plugin for iOS (Kotlin/Native) similar to Android’s kotlin-parcelize. The outcome is the new kotlin-parcelize-darwin plugin. Prologue Even though the main focus of this article is iOS, let’s take a step back and…

Achieving State Of The Art Results In Natural Language Processing

Part 2: ELMo, BERT and MT-DNN In my previous article I covered some of the fundamental concepts in NLP. This time, I will introduce ELMo, BERT and MT-DNN, architectures which leverage these concepts and have recently achieved some State Of The Art (SOTA) results on NLP tasks. Embeddings from Language Models (ELMo) An introduction to ELMo can be found in this…

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…

System under control — how to automate integration tests

Nobody wants to discover a production service laying down and not working, or even failing to behave as expected, with errors and incorrect data processing. On one occasion, we — Bumble, the parent company operating Badoo and Bumble apps — decided to greatly reduce such inappropriate behaviour through the use…

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…

Split Testing (A/B Testing) with Swift

Nowadays there are a million apps that solve users’ needs, so it is becoming hard to create something new or be better than market competitors. This has led to a situation where a lot of companies and startups are running experiments to find out which features are actually improving their…

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…

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…

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…

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…

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…

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…