Product/Diagramming

C4 diagrams anyone can draw, and everyone can read.

A fast, friendly canvas with the structure of the C4 model built in. Draw your systems in minutes, then go from the boardroom view to the engineering detail without redrawing a thing.

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A container diagram in Voussar for an insurance platform, with the component palette on the left and the diagram toolbar along the top.

The canvas

Drag, drop, connect. Done.

Everything you need is in the palette, and only what makes sense at the level you're on, so diagrams come out consistent without anyone policing them.

  • 162 cloud icons for AWS, Azure and Google Cloud, plus shapes and flowchart symbols.
  • One click to tidy. Auto-layout straightens a messy diagram instantly.
  • Lines that behave: add bends, move labels, and lines hop neatly where they cross.
  • Fast to work with: undo and redo, copy and paste, keyboard shortcuts and a table view.
A system context diagram with people, internal systems and third-party services.

Zoom in, zoom out

From the big picture to the detail in one click.

Double-click any system to open it up. Every level shares the same model, so names, owners and statuses always match, and the trail back up is always in view.

System context: policyholders, brokers and claims handlers using the Meridian insurance platform, and the partners it depends on.

Styling rules

Make what matters stand out, automatically.

Set a rule once, such as "anything deprecated is amber" or "anything holding personal data gets a badge", and every diagram follows it. Nobody has to remember to recolour anything.

  • Saved views let you switch between the version for engineers and the version for the board.
  • Presentation mode turns any diagram into a clean, read-only view for meetings.
  • Icon mode swaps boxes for cloud provider icons, ideal for stakeholders.
A diagram with conditional styling rules applied, highlighting elements by tag and status.

Flows Advanced

Walk anyone through how it works.

Lay a numbered scenario, like "a customer places an order", over a diagram you already have. Step through it in a meeting, or view it as a sequence diagram with one click.

  • No second diagram to maintain. Flows use the connections that are already there.
  • A sequence diagram for free, exportable for documents and slides.
A flow shown as numbered steps over a system context diagram, with the flows panel open.

Deployment

See exactly where everything runs.

Map your services onto environments, clusters and regions. The catalog then shows where every service is deployed, so "is this running in production?" has a straight answer.

A deployment diagram placing services into nodes within an AWS production environment.

And all the details you'd hope for.

Six diagram types

System context, container, component, landscape, deployment and free-form custom diagrams.

Find your way around

A minimap, a tree of every diagram, and breadcrumbs back to where you started.

Never lose work

Voussar warns you before one person's save overwrites another's changes.

See who's looking

Know when a colleague has the same diagram open before you start editing.

Light and dark

Work in whichever you prefer, and export in either.

Board-ready export

PNG, JPEG, SVG and PDF, with optional legend, header and version footer.

Architecture catalogOne source of truth for every system you run. Reviews & governanceSign-off, history and decisions with a paper trail. Integrations & exportSlack, Teams, wikis, Structurizr and more.

Put your architecture on solid ground.

Start free and bring one real system across. You'll know within an afternoon whether your diagrams can stay true.

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