Diagram as Code: PlantUML and Mermaid-Js

  • 5 September 2022
  • 32 replies

Userlevel 6

Hello Community,


We’re excited to announce that you can now create diagrams using code with Mermaid and PlantUML apps right in Miro. 


With these apps you can automate the process of generating complex diagrams with a simple text language — so you don’t have to worry about design and layout.

  • No need to align diagrams or manually update designs — design and layout are automatically applied

  • Copy your diagram code from other sources like GitHub or Notion to automatically re-create your diagram in Miro

  • Visit the Marketplace to install Mermaid and PlantUML 

  • Note, in this first version code will generate an image. We’re curious to hear your feedback and input for the next version


  1. Both apps support editing (only on newly created diagrams).
    1. To edit, select the image generated by one of the apps and then click the toolbar icon. The source of the original diagram will be loaded in the editor.
  2. Both apps are update to the latest version supporting new diagram types like C4 architecture
  3. All output generates a vector graphics so there’s no loss of quality when zooming in
  4. Full screen mode for more editing real estate
  5. Improved the speed of both apps

Visit our Help Center to learn more:

Share your ideas or work with the Miro Community and inspire others.

Happy Diagramming,


32 replies

Userlevel 3

Hi Turner, Thank you for the details. this is amazing to get PlantUML support in Miro. 

Is there any way I can modify a plantUML diagram after it has been added to the board.

Userlevel 6

Hi Arijt, thank you for your feedback. In this first version that’s not yet possible. But we’re taking in feedback from the Community, so glad you mentioned this!



Userlevel 3

Thanks Turner for the details. Will the code be available in any repo to go through?

Would love to have the ability to export diagrams from Miro to Mermaid code so we can backup some of our important diagrams and version them.

But awesome work!

Userlevel 2

Would be great if the code/syntax was kept, and could edited on the board, updating the image on the fly.

Would really help with collaborating around problems/ideas.

Great start though! 👍🏻

Userlevel 1

This is an awesome feature! Thank you.

Also, I agree with @Timothy Connolly. One of the main advantages of mermaid is making diagrams easy to change - solves the `Doc-Rot Catch 22` as the mermaid team highlight. I would use this if I could easily edit the mermaid code for the diagram.

FWIW, draw.io let’s you do this by double clicking on the created image to edit the underlying mermaid code:

More details at https://www.diagrams.net/blog/mermaid-diagrams

Userlevel 2

+1 to editing, it would be a great alternative to draw.io if the diagrams were mutable


I’m considering asking for the PlantUML miro app to be authorised for use in our company. However it would be good to know where your rendering service sits.

Do you have your own private rendering service which takes the PlantUML code and creates the image without the PlantUML code (i.e. data) leaving your domain or do you use a public rendering server?

Thanks in advance,


another +1 to editing!

Userlevel 6

Hi @Terry MR 

We host our own PlantUML rendering service, no data leaves our infrastructure.

Hope this is helpful,


Userlevel 1

Hi @Turner Pijpers ,

very excited by the mermaid app!

A couple of things:

  1. definitely need the edit functionality, I already got pretty mad at forgetting to copy-paste my diagram in a notepad before hitting “add to board” 😞
  2. the resolution of the image being added to the board is not high enough for complex/long sequence diagrams with a lot of information - the labels become unreadable when zooming in

Thank you!


Userlevel 4

@Turner Pijpers if it’s not documented already, you should include that information on hosting PlantUML in the documentation to help those that are reviewing the plugin for a later date.


Userlevel 1

Edit - NVM. Answered already. PlantUML rendering is on Miro services!

+1 for click-to-edit as a feature request. Mermaid.js integration is great, but not practically useful unless we can edit.

Userlevel 1

This is totally useless without storing source and editing

+1 for click-to-edit feature. It is indeed a must.

Also, seems that the render in mermaid differs from the one in https://mermaid.live/ as the code breaks in Miro but not the the live editor.

Did find if WBS is also supported. It marked with @startwbs-@endwbs tag. Is Miro works only with @startuml-@enduml?

Mermaid support is really great. But it would be so much more useful to be able to edit a diagram once it is created.

Mermaid and PlantUML support is nice to have.
It’s effectively the same as not having the feature without the ability to update the diagrams. I have to maintain the sequence generating source elsewhere or save the source code to the board in another format. 
My only workaround now is to copy paste the sequence code as a comment or text block on the generated image. 

Another +1 to the click to edit feature, currently it’s only good for migrating old mermaid diagrams over but not great for using mermaid in miro.

Is there a way of knowing where the release version of editing of Mermaid docs is on your development map? I’m going to be removing it from our Miro instance for now because this seems to be still in beta.


If you generate svg on the server-side, then https://kroki.io/ would be even better as it supports many other advanced text-to-diagram models. It can also be securely self-hosted.

Hi @Turner Pijpers ! 

What are your plans for supporting editing of these diagrams? Is it prioritised?

These are great tools but without editing they are kind of useless.


+1 for supporting editing - without that I am better off checking it into version control and using my IDE to render (plugins everywhere - the renderer is open source after all)

@Turner Pijpers is this coming up soon?