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Diagramming Tools

Diagrams communicate complex information visually. The right diagramming tool makes creating and maintaining technical illustrations efficient.

Text-Based Diagrams

Mermaid

Create diagrams in Markdown:

graph TD
    A[User] --> B[API Gateway]
    B --> C[Auth Service]
    B --> D[Core API]
    D --> E[(Database)]

Strengths: - Version controllable - No external tools needed - Renders in GitHub, GitLab, MkDocs

PlantUML

UML diagrams from text:

@startuml
actor User
User -> WebApp: Login
WebApp -> AuthService: Validate
AuthService --> WebApp: Token
WebApp --> User: Dashboard
@enduml

Strengths: - Comprehensive UML support - Many output formats - Extensive documentation

Visual Editors

Draw.io (diagrams.net)

Free, browser-based diagramming.

Strengths: - Free and open source - Works offline - Many templates - Exports to multiple formats

Excalidraw

Hand-drawn style diagrams.

Strengths: - Clean, informal look - Collaborative editing - Open source

Lucidchart

Professional diagramming platform.

Strengths: - Extensive shape libraries - Team collaboration - Integrations

Choosing a Tool

Need Recommendation
Version control Mermaid, PlantUML
Quick sketches Excalidraw
Professional diagrams Draw.io, Lucidchart
UML diagrams PlantUML
Architecture diagrams Draw.io, Mermaid

Best Practices

  1. Keep diagrams simple: One concept per diagram
  2. Use consistent styling: Colors, fonts, shapes
  3. Include legends: Explain symbols
  4. Version control sources: Track diagram changes
  5. Consider accessibility: Alt text, color contrast

Summary

Choose diagramming tools based on your workflow:

  • Text-based for version control and automation
  • Visual editors for complex diagrams
  • Keep diagrams simple and focused