NEWThe assistant now builds diagrams live
Architecture,
alive.
C4Stage is a living C4 canvas. Model your systems down to the component, ask the assistant to redraw them, and watch real production health flow through every box.
C1 → C4
Four levels, one canvas
Context to component — expand a system and drill all the way down.
∞
Nesting
Systems hold containers hold components. Expand as deep as the truth goes.
24/7
Watching production
Status dots read your real health probes and roll up through every level.
0
Stale diagrams
The canvas reads your systems — not your memory of them.
HOW IT STAYS ALIVE
Model it
Draw the estate once — C4 levels, nested as deep as the truth goes.
Wire it
Point each node at a health URL. That's the whole integration.
Talk to it
New service? Tell the assistant. The diagram redraws itself.
BUILT FOR ENGINEERS
Everything your architecture does, in one living space.
Model & nest
C4 levels with real nesting. Expand a platform into containers and components without ever leaving the canvas.
Talk to it
Tell the assistant what changed and watch it redraw the diagram live. Review the diff, keep it with one click.
Watch it run
Probes light every node and problems roll up to the surface. Flows replay a real request, step by step, over live status.
Shape it by hand
Drag a service into another container, pin an edge to a face, bow it around a neighbour — the map obeys your hand, and remembers.
Drill down, not across.
The C4 model is native, not a stencil: systems hold containers hold components, on one canvas. Expand a box to go a level deeper — the map stays put — and collapse it to fold the detail away. No tab-hopping between diagrams.
Healthy is quiet. Down glows.
Point a node at its health endpoint and the diagram becomes a status page: healthy stays a small green dot, a failing service glows red, and the rollup climbs through collapsed containers so the incident shows from the context view. Play a flow over it and the broken hop is the one lit red — you see exactly which journeys it takes down.
Boxes that carry their facts.
Every node holds its tech, its description, its tags — colored chips you define once and filter by everywhere. Hide a tag and the canvas dims to the slice you care about: just the PCI surface, just Tier 1, just what's deprecated and due. Filters ride the URL, so a slice is a link you can send.
Say it. It's drawn.
Describe the change in plain language. The assistant builds nodes, edges, and nesting live on the canvas while you watch — then hands you the whole thing as a reviewable draft.
Import
Paste Mermaid — a flowchart or a C4 diagram — and it's rebuilt on the canvas, boundaries, labels and all.
Export
PNG for the deck, SVG for the doc, PDF for the review — the whole diagram or just the flow that's playing.
Mermaid
Copy the whole model — structure and flows — as Mermaid source for the repo. It round-trips: what it writes, it can read back.
Every change, visible. Nothing, lost.
Every save is a version — walk the timeline, preview any of them read-only, restore the one that was right. And compare any two: teammate saves and assistant edits land as a diff on the canvas itself, green for added, red for removed, amber for changed. This one is live — the demo's real history, the platform's payment rewire, replayed.
Same canvas, together.
Presence, cursors, and a shared draft that merges as everyone types. Comments anchor to the boxes they're about — unread dots roll up through collapsed containers — and a teammate's save lands on your screen before they've said it's pushed.
Your AI reads the repo. The canvas draws itself.
Connect Claude Code — or any MCP client — with one command and hand it the intake prompt. It reads the codebase, grounds every node, edge and health URL in a file, and creates the canvas. Corrections arrive the way a teammate's would: a spark cursor travels to each node as it appears, then the change lands as a labelled version you can review or restore.
claude mcp add --transport http c4stage https://c4stage.com/api/mcpTokens are minted in your profile; the intake prompt and the five tools are in the docs.
One link. Everyone follows.
Hit Present and hand out a link — no accounts, no screen-share blur. Every viewer's canvas mirrors yours live: select a node and it highlights for the room, play a flow and they step through it with you. End the session — or just close the tab — and the link dies with it.
ALSO IN THE BOX
Share links
A read-only canvas behind an unguessable link, no account needed — the live demo you just explored is one.
Exports
PNG for the deck, Mermaid for the repo — diagram structure and flows both, one click each.
Command palette
⌘K from anywhere — jump to a node, a canvas, or a flow without touching the mouse.
HOW IT COMPARES
The living map, next to the drawing tools.
| C4Stage | IcePanel | Lucidchart | |
|---|---|---|---|
| C4 model with drill-down | Native — one canvas, C1 → C4 | Native | Shapes, not a model |
| Live production health on the diagram | Real probes, rolled up live | — | — |
| Request flows | Animated, played over live status | Step-through flows | — |
| AI assistant | Draws into your model, live | Writes descriptions | Generates static diagrams |
| Real-time co-editing | ✓ | ✓ | ✓ |
| Change review | Git-style diff on the canvas | Version history | Revision history |
| Price | Free tier · from $19.99 per editor | Per seat | Per seat |
Compared from the vendors' public product pages, September 2026. IcePanel and Lucidchart are trademarks of their owners; C4Stage is not affiliated with either.
PLANS
Free to start. Grow when the map does.
Thirty days free, no card: one system, two collaborators and the assistant. Paid tiers add room — more canvases, more people in the room, more of the assistant — and never take away what you already built.
Free
Thirty days to map one system.
$030-day trial · no card
- 1 workspace, 1 canvas, 2 flows
- 3 collaborators — you plus two
- 2 live presentation viewers
- 10 AI actions a month — assistant messages and MCP edits
Pro
For the person who keeps the map for a team.
$19.99per editor / month · $200 a year
- 3 workspaces, 10 canvases, 10 flows each
- 10 collaborators
- 25 live presentation viewers
- 300 AI actions a month
Studio
For an organisation with more than one map.
$49.99per editor / month · $500 a year
- Unlimited workspaces, canvases and flows
- Unlimited collaborators and viewers
- Unlimited AI actions (fair use)
- Priority support
Enterprise
White label, custom builds, your own infrastructure.
Custom
- White-label deployment
- Custom builds and integrations
- SSO and per-role access control
- A named contact
Every account starts on the thirty-day trial. Pick a plan when the map outgrows it. Compare plans →
“Every architecture diagram you've ever drawn is already out of date. This one keeps itself honest.”
— why we built C4Stage
See your own systems breathe.
Bring one diagram. Wire one probe. You'll never trust a static box-and-arrow picture again.