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The C4 model for software architecture
O modelo C4 de documentação para Arquitetura de Software
用于软件架构的C4模型
ソフトウェアアーキテクチャのためのC4モデル


Uses and benefits

The C4 model is an easy to learn, developer friendly approach to software architecture diagramming. Good software architecture diagrams assist with communication inside/outside of software development/product teams, efficient onboarding of new staff, architecture reviews/evaluations, risk identification (e.g. risk-storming), threat modelling (e.g. STRIDE/LINDDUN), etc.

Or watch "Visualising software architecture with the C4 model"

Introduction

Ask somebody in the building industry to visually communicate the architecture of a building and you'll be presented with site plans, floor plans, elevation views, cross-section views and detail drawings. In contrast, ask a software developer to communicate the software architecture of a software system using diagrams and you'll likely get a confused mess of boxes and lines ... inconsistent notation (colour coding, shapes, line styles, etc), ambiguous naming, unlabelled relationships, generic terminology, missing technology choices, mixed abstractions, etc.

A software architecture sketch

A software architecture sketch