System Architecture & App Flow Diagrams for Developers

Building software without visual documentation is like coding without comments — possible, but painful. Penguin is a visual editor that helps developers create architecture diagrams, workflow charts, and system designs without the complexity of traditional UML tools.

What Developers Use Penguin For

Software Architecture Diagrams

Document your system design with clear visual architecture:

Microservices topology
Database relationships
API gateway flows
Cloud infrastructure layouts

Create with AI: "Create a microservices architecture with API Gateway, Auth Service, User Service, Order Service, and shared PostgreSQL"

API & Data Flow Charts

Visualize how data moves through your system:

REST API request flows
GraphQL resolver chains
Event-driven workflows
Message queue patterns

State Diagrams

Map application states and transitions:

User authentication flows
Order processing states
Subscription lifecycle
Feature flag logic

Process Workflows

Document development processes:

CI/CD pipelines
Code review workflows
Deployment processes
Incident response procedures

Why Developers Choose Penguin

Speed Over Perfection

Traditional UML tools optimize for specification compliance. Penguin optimizes for speed. Create a diagram in 30 seconds, iterate as you code.

AI Understands Dev Context

Tell AI what you're building:

"Add error handling between API call and response parsing"

"Create a decision tree for user permission checks"

Local-First, Git-Friendly

Diagrams save as JSON files
Store alongside your code
Version control with Git
No cloud dependencies

Export for Documentation

PNG for README files
SVG for technical docs
JSON for backup and sharing

Real Developer Workflows

Architecture Decision Records

When proposing a new system design:

Sketch the architecture in Penguin
Export as PNG
Embed in your ADR document
Discuss with team

Sprint Planning

Visualize feature workflows before coding:

Create user flow diagram
Identify edge cases visually
Break into tickets
Reference diagram in PRs

Onboarding Documentation

Help new team members understand the system:

Document main data flows
Map service dependencies
Create state diagrams for complex features
Export to internal wiki

Getting Started

Download from Mac App Store
Create new diagram
Use toolbar or AI to add nodes
Connect with drag-and-drop
Export for your docs

Pro tip: Use auto-layout (Dagre algorithm) for clean hierarchical system diagrams.

Build better software with clear visual documentation. Try Penguin free.