Hello!

> Nitpick: no need for hanging indents in GNU ChangeLog messages.

Okay, fixed that.

> You'll want to break these long lines; we aim to limit line width below
> 80 columns.  'guix lint' should complain.

Done.

> All these FetchContent substitutions could perhaps be unnecessary if
> they were referring to the right package name and with the use of the
> -DFETCHCONTENT_TRY_FIND_PACKAGE_MODE=ALWAYS configure flag, which forces
> CMake to look at the packages from the system and fail if they aren't
> found instead of fetching their source and building them.

Unfortunately it seems that it does not work.  I checked it and cmake
wasn't able to to find libraries.  I'd prefer keep this as it is.  Maybe
I'll figure out how to do it in a more effective way later.

> The rest LGTM, although it'd be nice to modernize the definition to use
> gexps and remove the input labels.

Not sure how to properly handle things like this without input labels:

--8<---------------cut here---------------start------------->8---
       ("libigl-test-data"
        ,(origin
           (method git-fetch)
           (uri (git-reference
                 (url "https://github.com/libigl/libigl-tests-data")
                 (commit "19cedf96d70702d8b3a83eb27934780c542356fe")))
           (file-name (git-file-name "libigl-test-data" version))
           (sha256
            (base32 "1wxglrxw74xw4a4jmmjpm8719f3mnlbxbwygjb4ddfixxxyya4i2"))))
--8<---------------cut here---------------end--------------->8---

I'd prefer to keep input labels for now as it is more stylistic change
and does not affect the build.

- avp

-- 
Artyom "avp" Poptsov <poptsov.artyom@gmail.com>
Home page: https://memory-heap.org/~avp/
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