What syntax does the DSL use?

Three line kinds: `actor Name` (or `participant Name`) declares a lifeline, `A -> B: message` draws a message arrow (`-->` for dashed), and `note over A: text` adds a note. The page documents every form with examples.

Can I show self-messages?

Yes — `A -> A: loop back` renders a self-message with a loop-back arrow.

Are exports deterministic?

Yes. The same DSL source always renders the byte-identical SVG, so a committed source file always regenerates the same diagram.

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Sequence Diagram Maker — From Simple Text, In-Browser

Type actors and messages in a small documented DSL and get a rendered sequence diagram with lifelines and arrows. Export PNG/SVG, 100% private.

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How to use Sequence Diagram

1Declare your participants, one per line: actor User (or participant API).
2Add messages: User -> API: request. Use --> for dashed return arrows, and A -> A: text for self-messages.
3Optionally add notes with note over User: text (or note User,API: spans two lifelines).
4Export PNG or SVG — everything renders locally, nothing is uploaded.

Sequence Diagram FAQ

What syntax does the DSL use?: Three line kinds: `actor Name` (or `participant Name`) declares a lifeline, `A -> B: message` draws a message arrow (`-->` for dashed), and `note over A: text` adds a note. The page documents every form with examples.
Can I show self-messages?: Yes — `A -> A: loop back` renders a self-message with a loop-back arrow.
Are exports deterministic?: Yes. The same DSL source always renders the byte-identical SVG, so a committed source file always regenerates the same diagram.