Mermaid-cli and its dependency are taking up 90% of my system build time

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1

this issue is affecting me for some months already. Chromium takes over 2 hours to build and this happens over and over again.

What is the cause for these packages to never be available in the caches?

2

One likely cause could be that nobody uses the mermaid-cli pkg.

I recently tried it out to create an SVG of a graph, and then did the same in graphviz with dot. The latter produced way better diagrams, at least for my purposes. If others have a similar experience it would explain the lack of caching, by proxy of nobody using it.

3

I will look into it. Is its syntax supported in markdown renderings of different platforms like it is for mermaid?

let me test it:

graph graphname {
    a -- b -- c;
    b -- d;
}

at least not on discourse…

4

I did a quick check, and after a download of ~180 MB NAR, the CLI was there. No build happening.

What branch/channel are you using?

5

No I don’t think the code itself works. But it should be possible to embed the generated SVG.

6

I am using release-25.11 as flake input

7

Why? release-* is to nixos-* like master is to *-unstable…

Just use nixos-*.

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8

To be explicit, that is your precise problem, the release-* branches contain commits that haven’t been built by hydra yet, so you’ll have to build your own chromium pretty much every time you update.

Those branches are development targets, they’re not intended to be used as flake inputs. The nixos-* branches on the other hand can be used as flake inputs (though, personally, I recommend using the channel tarballs).

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9

Thanks! How haven’t I heard about that before?
And what are the staging branches for?

And in the home-manager repo there are just the release branches

10

It’s not intended for users. It’s all documented in the contribution docs: nixpkgs/CONTRIBUTING.md at c386eeffbb03ceb855cc0ab4368fbc5b02bf84f6 · NixOS/nixpkgs · GitHub

You’re only exposed to it because you’re using an experimental feature.

The channel tarballs are closer to what nix-channel users use.

home-manager and nixpkgs are unrelated projects, and don’t follow the same conventions.

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