> #x is for hexadecimal, right? If so, this can be simplified by using > the second argument of string->number: (string->number (string-drop > model 2) 16). >
So does this: --8<---------------cut here---------------start------------->8--- sl@matrixbox ~/guix [env]$ ./pre-inst-env guix shell --export-manifest gsl openblas gcc-toolchain --tune ;;; ("aarch64" #f #f #f #<<set> vhash: #<vhash 36d16e00 9 pairs> insert: #<procedure %insert (t-5ce36f5c768e728-317 t-5ce36f5c768e728-319)> ref: #<procedure vhash-assoc (key vhash #:optional equal? hash)>>) guix shell: tuning gsl@2.7 for CPU armv8-a ;; What follows is a "manifest" equivalent to the command line you gave. ;; You can store it in a file that you may then pass to any 'guix' command ;; that accepts a '--manifest' (or '-m') option. (use-modules (guix transformations)) (define transform1 (options->transformation '((tune . "armv8-a")))) (packages->manifest (list (transform1 (specification->package "gsl")) (transform1 (specification->package "openblas")) (transform1 (specification->package "gcc-toolchain")))) --8<---------------cut here---------------end--------------->8--- (I'm happy to provide ssh access to this rock64 if that can help.) Best, Sébastien