methodatlas
Architecture

C4 Model

Turns architecture context, options, and consequences into a tangible result by drawing system context, identifying containers, and adding code-level detail only when needed.

Core question
How can the system be described at the right level of detail for communication and decisions?
LowWorkshop + async1-4 h
Open runsheetPlan sessionStart comparison
Purpose

The method helps clarify architecture context, options, and consequences concretely. It organizes technical context, alternatives, and consequences. The result is captured as a context diagram, container diagram, and component diagram.

How it works

The team follows the steps: draw system context, identify containers, break important containers into components, and add code-level detail only when needed. Each step is captured visibly. At the end, a context diagram, container diagram, and component diagram are available so decisions, tests, or actions can follow directly.

Visual orientation

Method sketch for a quick mental model.

C4 Model · Zoom-in von Kontext bis CodeVier Ebenen vom Systemkontext bis zur Implementierung
C4 ModelVier Architektur-Ebenen zeigen den Zoom vom Systemkontext über Container und Components bis zum optionalen Code-Level.Architektur über vier Zoomstufen erklärenJede Ebene beantwortet eine andere Frage, ohne alle Details in ein Diagramm zu pressen.ZoomZoombei BedarfC1System ContextWer nutzt welches System?PersonNutzerSystemim FokusExternNachbarC2ContainerApps, APIs und DatenstoresWeb AppUIAPIBackendDatabaseDatenWorkerJobsC3ComponentBausteine im ContainerControllerEingangServiceLogikPolicyRegelnRepositoryPersistenzAdapterIntegrationC4CodeKlassen, Module, TestsService.tsModulPolicy.tsRegelRepo.tsDatenTestsBelegeSequenzDetailpfad

Flow

  1. 1Draw system context
  2. 2Identify containers
  3. 3Break important containers into components
  4. 4Add code-level detail only when needed

The runsheet guides execution with 5 phases, timeboxes, 5 pitfalls, and clear stop criteria.

Open runsheet

Ideal for

  • Architecture communication
  • Onboarding
  • Design reviews

Not good for

  • Domain discovery
  • Strategic market analysis

Deep dive

In detail

C4 Model follows a clear working logic: draw system context, identify containers, break important containers into components, and add code-level detail only when needed. This turns the method into a visible thinking process rather than only a conversation. Participants move step by step from raw material, observations, or options toward a shared structure. The result is a context diagram, container diagram, and component diagram that make decisions, learning, or further planning actionable.

Facilitation

Prepare a clear guiding question, the right information, and a visible workspace. Plan about 1-4 h with 1-5 people and use the format either in a workshop or asynchronously. The facilitation stays lightweight; short timeboxes, visible intermediate results, and a parking lot for open questions help.

Output artifacts
Context DiagramContainer DiagramComponent Diagram
Tags
diagramsarchitecturecommunicationvisualization

Sources

Introduction | C4 modelc4model.com
Artifact templates
C4 Model Working TemplateCompact working template for C4 Model with context, input, output artifacts, and next step.
canvas

c4-model-working-template.md

Compact working template for C4 Model with context, input, output artifacts, and next step.

C4 Model Working Template

Context

What is this method used for?

Core question

Which question should be answered at the end?

Input

Which data, observations, or materials are available?

Working area

  • Area 1:
  • Area 2:
  • Area 3:
  • Relationships / patterns:

Output artifacts

  • Context Diagram:
  • Container Diagram:
  • Component Diagram:

Open questions

  • ...

Next step

Owner, date, success signal.

When to choose differently

Short decision aid for existing alternatives.

Views and Beyond

Statt C4 Model, wenn du Architektur mit mehreren Sichten für Dokumentation und Stakeholder systematisch beschreiben willst.

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