Ghost Arc — build systems.
Ghost Arc combines real-time collaborative diagramming with an AI agent that designs system architecture from a single sentence — then generates a full technical spec.
Everything you need
Diagram faster, together.
From the first node to the finished spec, Ghost Arc keeps your whole team in sync — with AI doing the heavy lifting.
Real-time Collaboration
Multiple team members can work on the same canvas simultaneously. See each other's cursors, changes, and presence indicators live.
AI System Designer
Describe your system in plain English. The AI agent places nodes, draws connections, and builds your architecture on the canvas automatically.
Spec Generation
Turn your architecture diagram into a structured technical specification in seconds. Export as Markdown for documentation or sharing.
Rich Node Shapes
Express your architecture clearly with rectangles, circles, diamonds, cylinders, hexagons, and pill shapes — each color-customisable.
Smart Edges & Labels
Draw connections between services with smooth edges. Hover to highlight, single-click to select, double-click to add inline labels.
Shareable Rooms
Every project lives in its own room with a shareable link. Invite collaborators by email and manage access from within the editor.
How it works
From idea to spec in minutes.
Create a project
Open your dashboard and create a new project in seconds. Each project gets its own collaborative room.
Design with AI or drag-and-drop
Describe what you want to build in the AI chat, or drag shapes from the bottom panel and connect them by hand.
Collaborate and ship
Invite your team, iterate together in real time, then generate a spec document and export it for your engineering workflow.
Ready to map your system?
Ghost Arc is free to start. No credit card required. Open the editor, type what you're building, and let the AI handle the rest.