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Part F: Experience and Best Practices

Theory and practice intersect when organisations apply Architecture as Code principles across diverse contexts. This part synthesises lessons learned from real-world implementations, cross-disciplinary collaboration, and mature practices that span multiple domains.

Understanding the fundamental differences between related disciplines is essential before exploring their synergies. Documentation as Code versus Architecture as Code clarifies the distinct purposes these practices serve—communication versus structural enforcement—and explains how modelling tools like CALM and Structurizr differ fundamentally from diagram tools like Mermaid and PlantUML.

The various "as Code" disciplines—Documentation as Code, Requirements as Code, Policy as Code, Security as Code, and others—are most powerful when they work together rather than in isolation. Understanding how these practices interplay creates synergies that amplify value beyond what any single discipline delivers alone. The soft as code interplay shows how these seemingly distinct concerns actually reinforce one another.

Best practices emerge from the collective experience of organisations that have navigated Architecture as Code transformation successfully. These aren't theoretical ideals but pragmatic patterns proven across finance, public services, healthcare, and technology sectors. They reflect the reality that perfection is less important than consistent progress and the discipline to learn from both successes and setbacks.

The practices explored here draw on all previous parts—from the foundational principles through platform capabilities, security controls, delivery practices, and organisational transformation. They represent the integration of these distinct threads into cohesive, sustainable approaches.

What you will learn in this part:

• The fundamental differences between Documentation as Code and Architecture as Code
• How modelling tools (CALM, Structurizr) differ from diagram tools (Mermaid, PlantUML)
• How different "as Code" disciplines create synergies through integration
• Code organisation and modularity patterns that scale across teams
• Security and compliance patterns that balance protection with velocity
• Performance management in globally distributed architectures
• Governance models that empower teams whilst maintaining control
• Vendor and tool management strategies that reduce lock-in
• Continuous improvement practices that sustain long-term success

These experiences and patterns prepare organisations to anticipate future developments whilst maintaining effective practices today, setting the stage for the forward-looking perspectives in Part G.