[otsukare]

How would you do the things mentioned in the article using Guix?

You could write your own custom package definitions, extending the default to change up compile flags and allocators, but then you need to do this for every single package (and maintain them all). I'm not sure Guix gives you much here, though maybe that's fine for one or two packages.

The most pain-free option I can think of is the --tune flag (which is similar to applying -march=native), but packages have to be defined as tunable for it to work (and not many are).

Is there another option?

[dannymi]

    guix build --with-configure-flag="jq=CFLAGS=-O3" jq

If you want it to be permanent, then you can use a guix home profile (that's a declarative configuration of your home directory) with a patch function in the package list there:

    (define llama-tune
      (options->transformation `((tune . "znver3")))) ; Zen 3

    (home-environment
     (packages (list (llama-tune (specification->package "llama")))))

or:

    (define jq-patch
      (options->transformation `((with-configure-flag . "jq=CFLAGS=-O3"))))

[...]

    (jq-patch (specification->package "jq"))

[...]

You can also write a 10 line guile script to automatically do it for all dependencies (I sometimes do--for example for emacs). That would cause a massive rebuild, though.

>The most pain-free option I can think of is the --tune flag (which is similar to applying -march=native), but

> packages have to be defined as tunable for it to work (and not many are).

We did it that way on purpose--from prior experience, otherwise, you would get a combinatorial explosion of different package combinations.

If it does help for some package X, please email us a 2 line patch adding (tunable? . #t) to that one package.

If you do use --tune, it will tune everything that is tuneable in the dependency graph. But at least all dependents (not dependencies) will be just grafted--not be rebuilt.