Why this exists.

Last updated 6 September 2026

Every engineering organisation has an architecture diagram nobody reads. It is a wall of boxes with no beginning and no order, so the person who drew it ends up narrating it in a meeting — every time, to every new joiner, in every review — and the version in the wiki quietly stops matching the system.

The diagram is not the problem. The missing thing is a route through it: where a request starts, what it touches, what comes back, and which parts you can ignore for now. That is what a person supplies when they stand at a whiteboard, and it is exactly what the file in the repository throws away.

What it does

MermaidStage takes the Mermaid diagram you already keep beside your code and turns it into a narrated three-dimensional walk-through: a directed camera, chapter by chapter, that you can stop at any moment and explore by hand. The layout is deterministic, so the same diagram always produces the same scene, and a saved Stage replays the way it was authored rather than being recomputed.

The tour runs entirely in your browser. Playing a Stage calls no language model and sends your diagram nowhere.

What it does not do yet

Narration is your browser’s own voice, which sounds different on every machine and runs a different length. That is the honest reason you cannot yet share a Stage with somebody else: the same tour would not be the same tour. Generated narration is what unlocks sharing, publishing and embedding, and it is the thing being built now.

Turning prose into a diagram — describing a system and watching it draw itself — is designed and not built. Where the product says that, it means it.

Who is behind it

MermaidStage is built by Edge Ventures. It is early, it is in active development, and the people making it would rather hear that something is wrong than not: support@mermaidstage.com.

Questions about any of this: support@mermaidstage.com.