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…

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.

Add Superpowers to your Appium-Android tests

[Update]: I have now pushed this feature in new appium-espresso-driver upstream and it is available out of the box to everyone! Please refer to this medium blog for the latest happening Over the past few years, Appium has become one of the most widely used mobile automation tools. While there…

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…

Server-provided animations in iOS apps

Hi everyone! About six months ago we launched one of Badoo’s most exciting features: Live Streaming. One of its main functionalities is that viewers can send gifts to their favourite streamers to express their appreciation. We wanted to make the gifts as fancy and as engaging as possible, so it…

Checking your app’s paid services without losing money

Checking paid services is crucial in Badoo and Bumble apps testing process. Our applications are integrated with 70 payment providers in 250 countries. This means that bugs at any integration can seriously affect revenues, and in unpredictable ways. In this article, you will learn about methods that we employ in…

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…

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…

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…

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…

Swift 4.1 introduction of compactMap

In functional programming, we have a clear definition for what a flatMap function is supposed to be. The flatMap method takes a list and a transformative function (which expects zero or more values for each transformation), applies the transformative function to each member of the provided list, and produces 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…

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…

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…

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…

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…

Xcode 10.2, macOS Mojave 10.14.4, iOS 12.1 and other betas

New betas are here and these are some of the most important things that I have learned about them. Swift 5 for Xcode 10.2 beta Swift Firstly, the latest Xcode beta is bundled with the following Swift version: Apple Swift version 5.0 (swiftlang-1001.0.45.7 clang-1001.0.37.7) Target: x86_64-apple-darwin18.2.0 ABI version: 0.6 Let’s start with the most exciting news: Swift…

From zero to Cosmos — Part #3

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 finally became a complex unification project — a design system called Cosmos. From zero to Cosmos — Part #1 From zero to Cosmos —…

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…

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…

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…

Top 5 Bumble Android AMA

A few weeks ago, our Bumble — the parent company operating Badoo and Bumble apps — Android team hosted their first Ask Me Anything (AMA) session on Reddit. It was great! Our Android apps are huge: they have over 1.3 million lines of code, over 210 million downloads on the…

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…

#1 — Swift and iOS Ninjas Meetup: videos, slides and questions!

London isn’t just the capital of England — it’s also the capital of many other things. Including avoiding eye contact with people on the tube or trying to give you a free magazine. And it’s the capital of paying £12 for a cocktail because the barman has a beard. But…

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…