Draft Canvas Open editor

Draw software. Explain how it works.

A local-first canvas for turning architecture into a clear story. Sketch the idea, step inside the detail, walk the room through the flow.

Free and open source No account Nothing you draw is uploaded

A pencil sketch of an orders system, inked over as you watch. A storefront calls an orders API, which writes to an orders database and publishes to a queue; a fulfilment worker consumes it. A decision note on the database reads: charge before saving. The four connectors are numbered as the steps of one flow.

What it does

From a sketch to a story.

Fig. 01 Press a letter and the shape lands. Drag from its edge for what usually comes next.

Try it on your own repo

Hand your agent
the pencil.

Point Claude Code, Codex, Cursor, Gemini CLI or Junie at Draft Canvas Desktop. It reads the code, draws what’s really there, and shows its working. Minutes, not a meeting.

  1. Let it in.

    Open your project in the desktop app. In Settings → AI agents, turn on Allow agent access and pick your agent.

  2. Teach it the craft.

    Click Agent skill → Install skill. Now it knows shapes, depth and flows the way you do.

  3. Hand over the brief.

    Paste it into your agent and watch the sheet fill in.

Brief for your agent

Use the Draft Canvas skill to draw the architecture of this repository. Use appropriate C4 views, meaningful grouping boundaries, and look-inside details for key services. Attach decision notes, open questions and relevant code snippets to the shapes, connectors or boundaries they explain. Add presentation flows for the main request path and failure paths the code supports. Include source evidence and mark inferences.

Sheet
Your repo
Drawn by
Your agent
Checked by
You

A little space to think

Big ideas. Rough drafts.

You don’t need the whole picture to start.
Just a thought worth drawing out.

Draft Canvas Desktop v1.15.2

Put it on your desk.

Diagrams as files beside your code, a window of their own, and a door your coding agent can draw through.

Or, on a Mac with Homebrew

brew install --cask acltabontabon/tap/draft-canvas

First launch? The installers aren’t code-signed yet, so macOS and Windows warn you once. Here’s how to open it.

Prefer a tab? The browser editor needs no account and works offline; move between the two with a .draftcanvas file. All releases Privacy Self-hosting