Backstage Blog

• Android
• Mobile
• Testing
• Firebase

Testing mobile applications is not always an easy feat. In addition to defining what to test and determining how to write those tests, actually running tests can also be problematic — in particular, UI test suites running on real mobile devices or emulators sometimes run for an extensive amount of time.

• Project Management
• Engineering Management

One challenge engineering teams often face is dealing with work that doesn’t revolve around developing new features but that still requires the team’s attention and time. The Content Engineering Team here at SoundCloud is no exception, so we iterated on a process to deal with unplanned and support tasks to end up with fewer interruptions and more time to spend on implementing planned features.

• iOS
• Testing
• Mobile

Apple introduced automated UI testing in Xcode 7. This was a great addition for developers because this native support promised, among other things, an improvement in the flakiness notoriously associated with automation tests. As many of us developers have experienced, tests can sometimes fail even when there has been no modification to the test or underlying feature code.

• Search
• Data Science
• Machine Learning
• Analytics
• Data

SoundCloud consists of hundreds of millions of tracks, people, albums, and playlists, and navigating this vast collection of music and personalities poses a large challenge, particularly with so many covers, remixes, and original works all in one place.

• Learning
• Diversity
• Recruiting

Back in 2016, the SoundCloud People Team collaborated with engineering management in an effort to bring more junior engineers into the company. The result was DeveloperBridge, a paid junior engineering program that ran for 12 months and was based out of our Berlin headquarters.

• Architecture
• Microservices

A little less than two years ago, SoundCloud began the journey of replacing our homegrown deployment platform, Bazooka, with Kubernetes. Kubernetes automates deployment, scaling, and management of containerized applications.

• iOS
• Architecture

Growth in code bases come with exciting scalability challenges. As the size of our iOS codebase and team at SoundCloud grew, we faced challenges: long compile times and conflicts. Our productivity started to suffer as a result. We took inspiration from the work done in the backend (Building Products at SoundCloud) and applied it to mobile development. The main goal was to get back to a state where development is fun, fast, and would scale as the number of contributors grew. We modularized our iOS project by splitting it up into modules with well-defined responsibilities and public interfaces that interconnect them.

• Data Science
• Machine Learning
• Analytics
• Data

Here at SoundCloud, we’ve been working on helping our Data Scientists be more effective, happy, and productive. We revamped our organizational structure, clearly defined the role of a Data Scientist and a Data Engineer, introduced working groups to solve common problems (like this), and positioned ourselves to do incredible work! Most recently, we started thinking about the work that a Data Scientist does, and how best to describe and share the process that we use to work on a business problem. Based on the experiences of our Data Scientists, we distilled a set of steps, tips and general guidance representing the best practices that we collectively know of and agree to as a community of practitioners.

• Project Management
• Engineering Management

Product development flow (flow) is the rate at which our products are developed, from idea to deployment. Good flow means that products should pass through the development cycle quickly and continuously.

• Microservices
• Finagle
• Scala
• Functional Programming

If you’re a regular visitor to this blog, you might be aware that we have been transitioning to a microservices based architecture over the past four to five years, as we have shared insights into the process and the related challenges on multiple occasions. To recap, adopting a microservices architecture has allowed us to regain team autonomy by breaking up our monolithic backend into dozens of decoupled services, each encapsulating a well defined portion of our product domain. Every service is built and deployed individually, communicating with other services over the network via light-weight data interchange formats such as JSON or Thrift. What we haven’t touched on so far is how a microservice at SoundCloud looks backstage.