Diagram GitHub Repositories (2026) · Open Source Tools

Self-hosted homelab infrastructure visualizer — interactive network diagram with live status monitoring

Agent skill: describe your stack in a sentence, get an architecture diagram with official logos

A text diagram language where you say where things go. Playground: reladraw.github.io/reladraw

Generate diagrams from textual description

A Markdown Editor That Lives in Your Browser, Desktop, and a Single URL. Fast GitHub-style Markdown editing with live preview, diagrams, LaTeX, syntax highlighting, PDF export, and multi-tab support across web, desktop, and Docker.

The MIT-licensed infinite-canvas whiteboard SDK. An open-source tldraw alternative — no license fee, free for commercial use. React, React Native, and plain JS.

Whiteboard for Driving Scenarios🚗

This unofficial extension integrates Draw.io (also known as diagrams.net) into VS Code.

FlowGram is an extensible workflow development framework with built-in canvas, form, variable, and materials that helps developers build AI workflow platforms faster and simpler.

PlantUML Class Diagram Generator for golang projects

Digital timing diagram editor

Official public Markdeep source archive

ngDiagram – open-source Angular library for interactive diagrams, node-based editors, and workflow builders. Angular-first: signals and templates.

SwiftUI library to easily render diagrams given a tree of objects. Similar to ring chart, sunburst chart, multilevel pie chart.

A JavaScript rendering engine inspired by Flutter. Build any visualization — charts, diagrams, editors — with composable widgets and Canvas/SVG.

JavaScript architecture diagrams and dependency graphs

Software architecture diagramming tool. Includes a modern easy to use Frontend + Backend + CLI to enable managing diagrams from the shell or in CI.

groma.md - Your architecture as OKF Markdown in Git, and one C4 map you can walk. Scanned from source, curated by you and your agents.

Automatically generate PlantUML diagrams in javadoc

Generate Mermaid ERD from your Ruby on Rails application.