mermaid.js

Make a variety of diagrams using markdown-like syntax. From flowcharts, sequence diagrams, to pie charts and gantt charts.

Typora has mermaid.js diagram integration, but not current to what has been pushed to their live editor.

Flowchart

Sequence Diagram

Class Diagram

State Diagram

Entity Relation Diagram

User Journey

Gantt Chart

Pie Chart

Git Diagram