Domain Driven Design For Python


July 7th, 2019

55 mins 41 secs

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About this Episode


When your software projects start to scale it becomes a greater challenge to understand and maintain all of the pieces. In this episode Henry Percival shares his experiences working with domain driven design in large Python projects. He explains how it is helpful, and how you can start using it for your own applications. This was an informative conversation about software architecture patterns for large organizations and how they can be used by Python developers.


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  • Your host as usual is Tobias Macey and today I’m interviewing Harry Percival about domain driven design and enterprise application architecture in Python


  • Introductions
  • How did you get introduced to Python?
  • Can you start by explaining what "application architecture" is and how it compares to the types of application designs that Python developers and teams typically rely on? how does it contrast with "enterprise architecture"?
    • What are the influences that tend to lead engineers into sub-optimal architectures and how can they guard against them?
  • One of the core concepts in this problem space is that of "domain driven design". Can you unpack that term and explain the benefits that it provides to software architecture?
  • What are some of the other concepts that are common among application architecture patterns?
  • What are some of the common points of confusion among engineers who are first working with DDD?
  • Is there any particular size or scope of project and organization that merits the approach of domain driven design or is it applicable even at small scales of complexity and team size?
  • Now that we’ve convinced everyone that they should be using DDD can you talk through the steps involved in identifying and encapsulating the various implementation details that they will need to work through?
    • How does that process change when dealing with an existing application as opposed to a "greenfield" project?
  • How do Python language constructs and libraries impact the approach to implementation of application architecture patterns as compared to more traditional "enterprise" languages such as Java and C#?
  • What are some of the architectural anti-patterns to watch out for when implementing DDD?
  • On any given team, who is responsible for identifying and ensuring adherence to proper architectural principles?
  • Are there any publicly visible projects that implement DDD which listeners can look at and learn from?
  • To help Python developers in their efforts to learn and implement DDD and other aspects of enterprise architecture you have been working on a book. Can you talk about your motivation for that undertaking, what listeners can expect to learn when the read it, and any challenges that you have encountered in the process?
  • What are some trends in terms of system design and architecture, or technology influences, that you are keeping an eye on?

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