Diagrams as code
Write a few objects in Diagon's compact diagram language on the left; the diagram draws and lays itself out live on the right.
Desktop app · Windows / Linux · macOS soon
Diagrams that are code.
Write a few objects on the left, watch the diagram lay itself out on the right — then drag any node and its position is written straight back into your code. Both directions. Always in sync.
30-day free trial · €4.99/month or €49.90/year · cancel anytime
01The loop
round-trip
The loop
Write
a few objects in Diagon's compact diagram language.
Watch
the layout engine draw and arrange the diagram live.
Drag
any node — its position lands back in your code.
Describe
a diagram in plain words and let the local AI draft it.
02What makes it Diagon
4 capabilities
What makes it Diagon
Drag writes code
Grab any node with the mouse and its position is written straight back into your code. The source stays the single source of truth — both ways.
Its own layout engine
A custom layered auto-layout engine built for this language — no external diagram libraries, no browser-tab feel. A real desktop app.
AI that stays home
Describe a diagram in plain words and Diagon drafts it — with a model that ships inside the app and runs on your machine. Nothing leaves it. No account, no cloud.
03See it move
1.0
See it move
Demo video
Landing here with the 1.0 release.
04How buying works
How buying works
Try free. Subscribe when it earns its keep.
Every feature is free for 30 days — no account, no card. Then a subscription keeps the whole app unlocked — €4.99 a month, or €49.90 a year with two months free. Cancel anytime; when it ends, Diagon locks until you renew, and your diagrams — plain-text files — stay yours either way. Checkout, invoicing and VAT are handled by our merchant of record.
- Windows
- Linux
- macOS · soon
05Questions
4 answers
Questions, answered
- How does the trial work?
- Every feature, free for 30 days from first launch — no account, no card. After that, a subscription key — entered once — keeps the app unlocked.
- What does the subscription include?
- The full app and every update while it's active — €4.99 monthly, or €49.90 yearly (two months free). It renews itself with a tiny licence check when you're online; cancel anytime from the self-service link in your order confirmation. When it ends, Diagon locks until you renew — your diagrams are plain-text files and stay yours either way.
- Does the AI send my data anywhere?
- No. The model is bundled with the app and runs locally, so your diagram text never leaves your machine — not to us, not to anyone. The app does reach the network for two small things: if you use an icon URL in a diagram, that icon is fetched from the host you named, and a licence check sends your licence key and nothing else.
- Which platforms?
- Windows and Linux (AppImage + deb) today — each download is ~2 GB because the AI model ships inside the app. The macOS build is on its way.