Clickable Diagrams for Confluence → Mermaid apps

Your Mermaid app for Confluence stopped being maintained

What the options are — including the free ones.

What happened

Several apps that render Mermaid diagrams in Confluence were last updated in 2024 and sit on Connect, the platform Atlassian is retiring. Among them Mermaid for Confluence (around 700 installations) and Mermaid Integration for Confluence (around 590), both last touched in December 2024.

They still work today. They will not be updated again, and during 2026–2027 they stop rendering. See what Connect end of life actually means if this is new to you.

Your diagrams are safe. Mermaid is plain text. Whether it lives in a page or in an attached .mmd file, it is not locked inside anything.

Start here: you may not need to pay at all

We sell a diagram app, and we will still say this plainly: there are free, actively maintained Mermaid apps for Confluence. Search the Marketplace for "Mermaid" and sort by recent updates — several were released in 2026.

If all you need is "show this Mermaid text as a picture", install one of those and stop reading. Paying for a solved problem is not a good trade.

When a free renderer is not enough

Three cases, in our experience the only three that matter:

1. The diagram has to be navigable

An architecture map is not a picture, it is a menu. A person looks at the box labelled "Payments", wants the documentation behind it, and clicks. Free renderers give you an image; the click goes nowhere.

Mermaid supports links natively:

graph TD
  A[Payments service] --> B[(Ledger)]
  click A "https://your-wiki/display/OPS/Payments"

The question is whether your app honours that line, and whether the link keeps working after somebody renames the page.

2. You have more than one diagram format

Real wikis are mixed: Mermaid from the developers, draw.io from the architects, exported SVG from whoever used Visio. One app per format means three macros, three settings dialogs, three things to migrate next time.

3. The diagrams got big

Past thirty boxes, a rendered picture becomes unreadable in a page macro. You need search inside the diagram and a full-screen view, or nobody uses it.

What our app does with Mermaid

Feature	Detail
Flowcharts	`graph` and `flowchart`, all four directions (TD, TB, LR, RL, BT)
Shapes	box `[text]`, rounded `(text)`, decision `{text}`
Edge labels	`-->\|yes\|`
Links	`click A "..."`, to external URLs or pages in your own Confluence
Loops back	Handled — a "rejected, return to author" arrow does not stretch the layout into a ladder
Other formats	Same macro also reads SVG and draw.io files
Search	Type a word, matching shapes are outlined, the rest fades
Where it runs	Inside your own browser on your own site. Runs on Atlassian — no vendor servers

Not supported yet: sequence diagrams, class diagrams, state diagrams, Gantt charts, pie charts. Only flowcharts. If your diagrams are sequence diagrams, this app is the wrong tool today and we would rather you knew now.

How to use it

Save your Mermaid diagram as a file with a .mmd extension.
Attach it to the Confluence page.
Add the macro. The diagram is drawn from the text.

Keeping the diagram as a file rather than pasted into the page has a side benefit: the same file can live in your git repository, so the diagram and the code it describes change together.

Questions

Send your .mmd file to support@horizonventures.app and we will tell you whether it renders — before you install anything.