Learn the small Schemd grammar

01 / Nodes

Place a component on a bounded canvas

Every fence needs bounds="WIDTHxHEIGHT". Both dimensions must be integers from 64 to 4096.

A node has one predictable shape:

text

                    
                1
                kind:ID "label" at (x, y) color [options]

IDs are case-sensitive. Coordinates use the SVG viewBox, and options depend on the node kind. The color can be a built-in token such as #blue, a safe CSS color, or a theme alias.

02 / Connections

Connect named ports

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A connection is just as small:

text

                    
                1
                ID.port -> ID.port color [options]

Choose line, bezier, or ortho. Orthogonal routes leave component bodies through a short escape segment, avoid other node bounds, and fail with a useful error if no clear route exists.

Markers are optional: marker-start=... and marker-end=... accept none, arrow, open-arrow, dot, triangle, diamond, or diamond-filled.

03 / UML

Use relationship names instead of hand-built markers

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UML relationships are connection options. Schemd supplies the usual marker and dash pattern, while an explicit marker or solid/dashed option can override the default.

Relation	Default style
`association`	Solid line
`dependency`	Dashed, open arrow
`generalization`	Hollow triangle at the target
`realization`	Dashed, hollow triangle at the target
`aggregation`	Hollow diamond at the source
`composition`	Filled diamond at the source
`message`, `transition`	Open arrow
`include`, `extend`	Dashed, open arrow, automatic label

Add label="text" when the connector needs a name.