One model.
Every diagram.
Always right.

Voussar keeps every architecture diagram in your organisation accurate. Map your systems once, share them across every team, and always know what you run, who owns it and what breaks if it changes.

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Free plan, no card needed 14-day trial of every paid plan Hosted in the UK

Your architecture diagrams are already out of date.

Every team draws its own. The same service ends up in a dozen slide decks, wiki pages and whiteboards, each one slightly different. The moment it's renamed, retired or handed to a new owner, most of those copies are wrong, and nobody knows which.

And that costs more than anyone budgets for.

  • Slower onboarding. New starters learn your estate from whoever has time to explain it, not from the documentation.
  • Riskier change. Teams find out what a change touches during the incident, rather than before it.
  • Painful audits. When someone asks who approved a design, and what it looked like at the time, there's no answer.

Voussar fixes it at the source.

Every system is described once, in one catalog the whole organisation shares. Every diagram is drawn from it. Change something once and every diagram, in every team, is right straight away.

The platform

Everything your architecture practice needs, in one place.

Diagrams, catalog, reviews and history that work together, so the picture your teams rely on is the one that's true.

A container diagram for an insurance platform in Voussar: customer and broker channels behind an API gateway, core services, and the data store each service owns.
  • Context, container and component views
  • 162 cloud icons
  • Auto-tidy layout
Explore diagramming
1 changeupdates every diagram that uses it, in every team
6diagram types, from the big picture to deployment
162AWS, Azure and Google Cloud icons built in
UKhosted on Microsoft Azure, encrypted throughout

Impact analysis

Know what breaks before you change it.

Open any system and see everything that depends on it, how far the knock-on effects reach, and every diagram it appears in, across the whole organisation.

  • Plan changes with confidence. No more discovering the blast radius during the outage.
  • Retire legacy safely. See exactly who still relies on it before you switch it off.
  • Answer in seconds, not after a week of asking around.
An element profile with relationships, an impact analysis and where it is used.

Reviews & approvals

Sign-off that actually means something.

Designs go to the right people for approval, and only approved work reaches the shared catalog. Every decision is recorded with who made it, when and why.

  • Choose your approvers, and how many of them must agree.
  • Keep decision records alongside the systems they affect.
  • Hand auditors the evidence: what was approved, by whom, and what it looked like at the time.
Explore reviews & governance
Change history with save comments, approved snapshots and compare and restore actions.

AI assistants

Your AI assistant, fluent in your architecture.

Connect Claude, ChatGPT or any assistant that supports MCP. Ask it questions about your estate, or have it draft new diagrams and decision records for your team to review.

  • Answers grounded in your real estate, not guesses.
  • Nothing changes without review. Diagrams an assistant drafts go through the same approvals as your team's work.
  • Your data stays yours. Voussar sends nothing to an AI provider, and you choose who may connect.
See how AI access works
We're retiring the legacy rating engine next quarter. What still depends on it?
search_elements · get_element
Three things still call it: Quote & Bind, the Broker Portal and the nightly renewals batch. It appears on four diagrams across two teams, and the renewals batch is marked business critical.
Draft a decision record for the migration.
create_adr
Done. "Retire the legacy rating engine" is saved as a proposed decision, ready for your team to review.
An example conversation in Claude, using Voussar's AI tools

Data flows

Know where your personal data goes.

Record every integration between your systems: what it carries, how often, who owns it, and what happens if it stops. Your data protection and resilience teams get a live register instead of a spreadsheet.

  • Personal data classified on every flow, from none to special category.
  • Criticality recorded, so you know which outages hurt.
  • Always current, because the register and the diagrams are the same thing.
Explore data flows
The organisation-wide data flow register.

Built on the C4 model

From the big picture to the detail in one click.

Show the board how the business fits together, then double-click to show an engineer exactly how one service works. Same model, same names, every level.

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

Who it's for

Built for organisations with more than one team.

Heads of architecture

One trusted picture of the whole estate.

Stop chasing teams for updates. Set the standard once, and get a review process that makes "approved" mean something.

Engineering & platform teams

Publish once. Never redraw it again.

Other teams reference your services instead of copying them, so when you change something they see it the same day.

CTOs, risk & compliance

Evidence on demand.

Who approved what and when, where personal data flows, and an audit trail nobody can edit. Ready when the auditor asks.

And much more

Everything you'd expect, and plenty you wouldn't.

Freshness trackingSee what hasn't been checked recently, and remind its owner automatically. Decision recordsCapture why, not just what, linked to the systems it affects. Flows & sequence diagramsWalk through any scenario step by step, on the diagram you already have. Deployment diagramsShow which services run where, in every environment. Styling rulesColour anything deprecated, critical or customer-facing automatically. Comments & mentionsDiscuss any system or connection, and get a daily digest of what matters to you. Slack & Microsoft TeamsApprovals, changes and comments, sent where your teams already work. Live wiki embedsPut diagrams in Confluence or your intranet, and they stay up to date. Structurizr import & exportBring an existing model across, and take it with you any time. PNG, SVG & PDF exportBoard-ready diagrams with legends, headers and version footers. Single sign-on & 2FASign in with your identity provider, and require it across the organisation. Tamper-proof audit logEvery administrative action recorded, and exportable to CSV.

Pricing

Simple pricing for the whole organisation.

One flat price per organisation, however many diagrams you draw within your plan. Start free, and try any paid plan free for 14 days.

Free

Try Voussar on one real system, for as long as you like.

£0forever

No card needed

Start free
  • 1 workspace and 4 diagrams
  • 2 people
  • 10 shared catalog entries
  • Impact analysis and change history
  • AI assistant access
  • PNG export

Basic

For one team that wants its architecture done properly.

£49/ month

or £490 a year, 2 months free

Start 14-day trial
  • Everything in Free, plus:
  • 5 workspaces and 25 diagrams
  • 10 people and 5 groups
  • 100 shared catalog entries
  • Reviews and approvals
  • Architecture decision records
  • Share links and custom colours
  • JPEG and SVG export
Recommended

Advanced

For multiple teams and departments working from one model.

£149/ month

or £1,490 a year, 2 months free

Start 14-day trial
  • Everything in Basic, plus:
  • 25 workspaces and 150 diagrams
  • 50 people and 50 groups
  • 1,000 shared catalog entries
  • Flows and sequence diagrams
  • Mark the version everyone should use
  • Slack, Teams and webhooks
  • Live wiki embeds
  • PDF export

Enterprise

For the whole organisation, with single sign-on.

£499/ month

or £4,990 a year, 2 months free

Talk to sales
  • Everything in Advanced, plus:
  • Room for up to 100,000 people, diagrams and workspaces
  • Single sign-on with your identity provider
  • Require SSO for everyone
  • The highest AI and API allowance

Prices in GBP, excluding VAT. Compare every feature

Questions

What buyers ask us.

How is Voussar different from Visio, Miro or Lucidchart?

Drawing tools store pictures. Voussar stores your architecture itself: each system is described once, with an owner, a status and a history, and every diagram is drawn from that shared description. Change it once and every diagram is right, in every team. You still get a fast, friendly canvas on top.

Do we have to know the C4 model to use it?

No. C4 gives your diagrams a consistent shape, and Voussar guides you through it by only offering what makes sense at each level. If you already use C4, you'll feel at home immediately. If not, it's the easiest way to start.

Can we bring in our existing diagrams?

If your architecture is already described in Structurizr, you can import it directly. Otherwise most teams start by drawing one important system, then publishing its parts to the catalog so every other team can reuse them.

Is our data safe?

Voussar is hosted in the UK on Microsoft Azure. Your data is encrypted in transit and at rest, each organisation's data is kept separate, and every administrative action is written to an audit log that can't be edited. Single sign-on and two-factor authentication are both available.

What happens when we reach a plan limit?

Nothing you've already built is removed or locked. Voussar simply tells you when the next diagram or invitation would go over your plan, and upgrading lifts the limit straight away.

Can we change plan, or pay annually?

Yes. You can move between plans at any time from your settings and it takes effect immediately, with charges worked out to the day. Pay monthly, or annually and get two months free. VAT invoices are available as PDFs.

Does the AI read our data?

Voussar doesn't run any AI of its own and sends nothing to an AI provider. If you choose to connect your own assistant, such as Claude or ChatGPT, it reads only what the person connecting can see, and your organisation's owners decide who may connect at all.

Is there a free trial?

Every paid plan comes with a 14-day free trial. You set up a Direct Debit when you sign up, and nothing is collected until the trial ends. The Free plan needs no payment details and never expires.

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.

Start free, no card needed Book a demo

Free plan forever · 14-day trial of every paid plan · Hosted in the UK