Mermaid Chart

Dev tools

diagramming editor

SHOW HN2025

230points
59comments
#266of 3,837 in 2025
Top 7%of 2025 by points

How HN took it

MixedNo clear lean

5 positive, 17 neutral or asking, 3 mixed, 10 critical, out of 35 comments about the project. Thread score -0.09.

Design: 3 for, 2 againstExecution: 0 for, 3 againstIdea: 0 for, 3 againstPerformance: 0 for, 1 againstDocs: 0 for, 1 against

The thread, comment by comment

Each row is a top-level comment and its replies, in HN's order. Select a cell to open that comment on HN.

positive neutral or mixed critical about another commenter or something else the maker

What HN said

What people liked

  • Useful for adjusting styling and layout of Mermaid diagrams

    From 2 comments
    • My front end to mermaid is usually claude. I can’t count how many times trying to convey a complicated idea (last week, a one time use token in a 3 party where my backend can’t…
      MarkMarine on HN
    • I haven’t had issues with it enough to notice, but I do tolerate it making code mistakes as just part of the deal now. I fix the little errors (claude said it made a deps.edn…
      MarkMarine on HN
  • Sequence diagram editor is better than alternatives

    From 1 comment
    • FWIW, I find MermaidChart's sequence diagram editor better than the sequencediagram.org one!
      sebmellen on HN

Objections

  • Whiteboard layout breaks and boxes overlap

    From 2 comments
    • I spent some time playing around with this recently and loved it at first. I also realized ChatGPT is pretty good at generating Mermaid diagrams (didn't try your own AI…
      philfreo on HN
    • > it just wouldn't let me organize/drag things where I wanted, and I couldn't get things to not overlap I suspect this might be a fundamental issue with mermaid. I've always had…
      LordDragonfang on HN
  • Mermaid layout engine is weak and renders poorly

    From 2 comments
    • The only reason anyone uses mermaid is because it's low friction and most editors support it out of the box or through plugins. But its layouting engine sucks and everything…
      Vampiero on HN
    • I only use diagramming tools with automatic layout algos to generate visualizations programmatically to debug things. For documentation purpose, I largely prefer to draw them by…
      Xmd5a on HN
  • Sign-up required before trying the editor

    From 1 comment
    • You lost me at Create your account. I would just want to play with the editor and store in the local browser storage until I decide I like it.
      webprofusion on HN
  • Bundle size of mermaid.js is too large

    From 1 comment
    • Please forgive my posting on the broader topic of Mermaid... The Mermaid package has gotten much bigger recently. Compare mermaid.min.js across a sampling of major releases: ```…
      infogulch on HN

Requests

  • Improve whiteboard and layout control

    From 2 comments
    • This is definitely a gap in current Mermaid functionality. This is a gap we're aiming to close in 2025. Significant Whiteboard improvements and expanded diagram support is on the…
      dominicdewalt on HN
    • Hi there, Mermaid CEO here:) I hear you on the whiteboard. It's still in its early days. Should be substantially improved in the coming months. To clarify on mermaidchart.com and…
      AFirestone on HN
  • Headless or browserless rendering outside browsers

    From 2 comments
    • Any idea when Mermaid diagrams will render outside of web browsers? https://github.com/mermaid-js/mermaid/issues/2485 <rant> Aside, I'm the author of KeenWrite…
      thangalin on HN
    • Hello Dominic. Seconding the question on browserless rendering in the other comment. Having to (unseccessfully for us so far; the text renders incorrectly) tweak selenium setups…
      baobun on HN
  • More layout algorithms and better aesthetics

    From 2 comments
    • I have been using the beta and would certainly appreciate a few more layouts. You can have a look at yEd for inspiration. Otherwise, it looks very promising!
      dr_kiszonka on HN
    • I think the main reason why diagrams are not used as often as they should to document code bases is that we developers have to face opposite yet complementary approaches: text…
      Xmd5a on HN
  • VSCode integration

    From 1 comment
    • I used this recently as someone shared a link to a diagram at work and I edited it for my own comprehension. It's nice. I'd prefer to have this in VSCode tho!
      nejsjsjsbsb on HN

Questions

  • Difference between mermaidchart.com and mermaid.live

    From 1 comment
    • I spent some time playing around with this recently and loved it at first. I also realized ChatGPT is pretty good at generating Mermaid diagrams (didn't try your own AI…
      philfreo on HN
  • Whether Mermaid supports generics in class diagrams

    From 1 comment
    • Do Mermaid class diagrams support generics (parameterized types)?
      mlhpdx on HN

Alternatives named

  • Draw.io

    From 1 comment
    • With Draw.io embedding Mermaid diagrams and plug-ins available for VSCode and other IDEs, why is this so special?
      sergius on HN
  • sequencediagram.org

    From 1 comment
    • Nice! I love how mermaid keeps getting better! For sequence-diagrams, nothing beats https://sequencediagram.org/ (I am not connected with them in any way, just a happy user)
      maho on HN
  • PlantUML

    From 1 comment
    • That's pretty cool. Wish PlantUML community would have something like it.
      ConfusedDog on HN
  • Excalidraw

    From 1 comment
    • I settled on excalidraw via obsidian https://github.com/zsviczian/obsidian-excalidraw-plugin
      bastardoperator on HN
  • D2 and TALA

    From 1 comment
    • We make (and sell) one, you can play with it here: https://play.d2lang.com/?script=qlDQtVOo5AIEAAD__w%3D%3D&layout=tala& Bigger example:…
      terrastruct on HN

Category, keywords, summaries and labels on this page were made by AI (Thread Reader v2) and not checked by hand. Each point links to the comments it came from.

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