Training by Simon Brown: Visualising software architecture with the C4 model

"Visualising software architecture with the C4 model" is a hands-on, 1-day workshop that focuses on the visualisation and communication of software architecture using the C4 model. The core of this workshop can be based upon a simple case study (an architecture kata) or your own software systems. This workshop will give you some pragmatic, practical and lightweight techniques that you can apply to your work the very next day. You'll learn why most software architecture diagrams are meaningless, how to critique them, how to fix them and how to use the C4 model to create a simple yet powerful set of developer-friendly diagrams to describe software architecture.


It's very likely that the majority of the software architecture diagrams you've seen are a confused mess of boxes and lines. Following the publication of the Manifesto for Agile Software Development in 2001, teams have abandoned UML, discarded the concept of modelling, and instead place a heavy reliance on conversations centered around incoherent whiteboard diagrams or shallow "Marketecture" diagrams created with Visio. Moving fast and being agile requires good communication, yet software development teams struggle with this fundamental skill. A good set of software architecture diagrams are priceless for aligning a team around a shared vision, and for getting new-joiners productive fast.

This hands-on workshop explores the visual communication of software architecture, and is based upon years of experience working with software development teams large and small across the globe. We'll look at what is commonplace today, the importance of creating a shared vocabulary, diagram notation, and the value of creating a lightweight model to describe your software system. The workshop is based upon the "C4 model", which I created as a way to help software development teams describe and communicate software architecture, both during up-front design sessions and when retrospectively documenting an existing codebase. It's a way to create maps of your code, at various levels of detail. Static structure, runtime and deployment diagrams are all covered, so you'll be able to tell different stories to different audiences.


  • [09:00 - 09:15] Introduction
  • [09:15 - 10:30] Software diagramming exercise 1
  • [10:30 - 11:00] Break
  • [11:00 - 12:00] Review and feedback
    • Diagramming anti-patterns and typical problems
    • The "model-code gap"
  • [12:00 - 13:00] Lunch
  • [13:00 - 14:00] C4 model - core diagrams
    • Abstractions and creating a shared vocabulary with a ubiquitous language
    • An overview of the C4 model
    • Notation and tips for better diagrams
    • System Context diagrams
    • Container diagrams
    • Component diagrams
  • [14:00 - 15:30] Software diagramming exercise 2
  • [15:30 - 16:00] Break
  • [16:00 - 16:30] C4 model - supplementary diagrams
    • C4 and UML
    • System Landscape diagrams
    • Dynamic diagrams
    • Deployment diagrams
    • Frequently asked questions
  • [16:30 - 16:45] Tooling
    • Diagrams vs models
    • Extracting software architecture information from code and "architecturally-evident coding styles"
  • [16:45 - 17:00] Discussion, questions and wrap-up