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Mermaid
An open JavaScript diagramming tool whose concise syntax generates flowcharts, sequences, state diagrams, journeys, Git graphs, and timelines.
Visit official siteContent record updated Aug 1, 2026Official site reached automatically · Checked Aug 3, 2026
Why it’s here
Embedding diagrams in repository docs gives design reviews, diffs, and site publishing the same workflow as code, ideal for living system explanations.
Best fit
Prototype systems, stories, and interactions, then validate them with real players.
documentationsystems-design
Before you commit
Complex layout and pixel-level styling are limited, and renderer versions can change output; do not send secret diagrams to an uncontrolled online editor.