Python at Zalando


September 10th, 2016

40 mins 26 secs

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About this Episode


Open source has proven its value in many ways over the years. In many companies that value is purely in terms of consuming available projects and platforms. In this episode Zalando describes their recent move to creating and releasing a number of their internal projects as open source and how that has benefited their business. We also discussed how they are leveraging Python and a couple of the libraries that they have published.

Brief Introduction

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  • Your hosts as usual are Tobias Macey and Chris Patti
  • Today we’re interviewing Jie Bao and João Santos about their use of Python at Zalando

Interview with Zalando

  • Introductions
  • How did you get introduced to Python? – Tobias
  • Can you start by telling us a bit about what Zalando does and some of the technologies that you use? – Tobias
  • What role does Python play in your environment? – Tobias
  • Is the use of Python for a particular project governed by any particular operational guidelines or is it largely a matter of developer choice? – Tobias
  • Given that you have such a variety of platforms to support, how do you architect your systems to keep them easy to maintain and reason about? – Tobias
  • One of the projects that you have open sourced is Connexion. Can you explain a bit about what that is and what it is used for at Zalando? – Tobias
  • What made you choose to standardize on Swagger/OpenAPI vs RAML or some of the other API standards? – Tobias
  • Did Connexion start its life as open source or was it extracted from another project? – Tobias
  • ExpAn is another one of your projects that is written in Python. What do you use that for? – Tobias
  • Can you describe the internal implementation of ExpAn and what it takes to get it set up? – Tobias
  • Given the potential complexity of and the need for statistical significance in the data for proper A/B testing, how did you design ExpAn to satisfy those requirements? – Tobias
  • Given the laws in Germany around digital privacy, were there any special considerations that needed to be made in the collection strategy for the data that gets used in ExpAn? – Tobias

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The intro and outro music is from Requiem for a Fish The Freak Fandango Orchestra / CC BY-SA