Mermaid

The most straightforward diagramming solution is Mermaid, which is integrated directly into Obsidian.

```mermaid
flowchart LR
    A <--> B
```

yields

flowchart LR
    A <--> B

As a bonus, this also works in Quartz for static site diagramming.

See also

Graphviz

The second-most straightforward approach seems to be Graphviz. There’s a community plugin for it which will automatically render dot code blocks:

```dot
digraph G {
    Hello -> World;
}
```

becomes

digraph G {
    Hello -> World;
}

From there, see the Graphviz docs.

See also