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Android at scale @Square

Ralf Wondratschek

Software Engineer


Ralf is a software engineer at Square. He maintains several open-source projects on Github, e.g. android-job, which is used by many other companies like Twitter, Dropbox, Square, Pocket and The New York Times. Prior to Square, Ralf worked at Evernote and several several companies in Germany and published as independent developer four apps in the Google Play Store.


Codebases naturally grow over time by adding new features, abstractions and migrating code to new architectures. We introduce layers to hide implementation details and separate concerns. Good modularization brings many benefits such as better reusability, shorter build times and code isolation. Square builds payment, software and hardware systems that help businesses of any type. The Android Point of Sale repository faces challenges similar to other large codebases. This talk gives an overview of how the repository evolved over the years, the difficulties we encountered in the recent months and how we addressed them with clear structures and common patterns to keep up with the ongoing growth.