drawioseq

Generate draw.io sequence diagrams from plain-text .seq files — automatically on every save.

How it works

1. Open or create a .seq file in your workspace
2. Write your sequence diagram using the drawio-seqgen syntax
3. Save the file — a .drawio file is generated automatically right next to it
4. Open the .drawio file in Draw.io Integration to see your diagram live

The extension also provides:

• Syntax highlighting — keywords, participant names, arrows, labels, and comments are all coloured
• Syntax checking — parse errors are underlined in red; semantic hints (unclosed blocks, activated participants that are never deactivated, unknown participant names) are shown as grey/blue dotted underlines directly in the editor

Source

The source code for this extension is available at github.com/ldaschinger/drawioseq-vscode-extension.

Requirements

Python 3 must be installed and available on your PATH as python3 or python. No additional Python packages are needed — lark is bundled with the extension.

Syntax

For the full syntax reference see the drawio-seqgen repository.

This extension is compatible with the drawio-seqgen tool as of version 1.4.26.

Commands