Hello Guix! When someone’s working on a channel, it’s typical to have that channel already in your ‘guix’ and to use ‘guix build -L /path/to/checkout PKG’ to test a package from a working copy of the channel. Here’s what it looks like: --8<---------------cut here---------------start------------->8--- $ cat ~/.config/guix/past-channels.scm (cons (channel (name 'guix-past) (url "https://gitlab.inria.fr/guix-hpc/guix-past") (introduction (make-channel-introduction "0c119db2ea86a389769f4d2b9c6f5c41c027e336" (openpgp-fingerprint "3CE4 6455 8A84 FDC6 9DB4 0CFB 090B 1199 3D9A EBB5")))) %default-channels) $ guix pull -p /tmp/test -C ~/.config/guix/past-channels.scm [...] $ /tmp/test/bin/guix build -L ~/src/guix-past/modules autoconf@2.59 -n ;;; note: source file /home/ludo/src/guix-past/modules/past/packages/assembly.scm ;;; newer than compiled /gnu/store/6b0ww9dxvfig7wdxqcyjs0hlw331la4z-guix-past/lib/guile/3.0/site-ccache/past/packages/assembly.go ;;; note: source file /home/ludo/src/guix-past/modules/past/packages/autotools.scm ;;; newer than compiled /gnu/store/6b0ww9dxvfig7wdxqcyjs0hlw331la4z-guix-past/lib/guile/3.0/site-ccache/past/packages/autotools.go ;;; found fresh local cache at /home/ludo/.cache/guile/ccache/3.0-LE-8-4.3/home/ludo/src/guix-past/modules/past/packages/autotools.scm.go ;;; note: source file /home/ludo/src/guix-past/modules/past/packages/backup.scm ;;; newer than compiled /gnu/store/6b0ww9dxvfig7wdxqcyjs0hlw331la4z-guix-past/lib/guile/3.0/site-ccache/past/packages/backup.go ;;; found fresh local cache at /home/ludo/.cache/guile/ccache/3.0-LE-8-4.3/home/ludo/src/guix-past/modules/past/packages/backup.scm.go ;;; note: source file /home/ludo/src/guix-past/modules/past/packages/guile-xyz.scm ;;; newer than compiled /gnu/store/6b0ww9dxvfig7wdxqcyjs0hlw331la4z-guix-past/lib/guile/3.0/site-ccache/past/packages/guile-xyz.go ;;; found fresh local cache at /home/ludo/.cache/guile/ccache/3.0-LE-8-4.3/home/ludo/src/guix-past/modules/past/packages/guile-xyz.scm.go ;;; note: source file /home/ludo/src/guix-past/modules/past/packages/boost.scm ;;; newer than compiled /gnu/store/6b0ww9dxvfig7wdxqcyjs0hlw331la4z-guix-past/lib/guile/3.0/site-ccache/past/packages/boost.go ;;; found fresh local cache at /home/ludo/.cache/guile/ccache/3.0-LE-8-4.3/home/ludo/src/guix-past/modules/past/packages/boost.scm.go ;;; note: source file /home/ludo/src/guix-past/modules/past/packages/graphviz.scm ;;; newer than compiled /gnu/store/6b0ww9dxvfig7wdxqcyjs0hlw331la4z-guix-past/lib/guile/3.0/site-ccache/past/packages/graphviz.go ;;; note: source file /home/ludo/src/guix-past/modules/past/packages/maths.scm ;;; newer than compiled /gnu/store/6b0ww9dxvfig7wdxqcyjs0hlw331la4z-guix-past/lib/guile/3.0/site-ccache/past/packages/maths.go ;;; note: source file /home/ludo/src/guix-past/modules/past/packages/maths.scm ;;; newer than compiled /home/ludo/.cache/guile/ccache/3.0-LE-8-4.3/home/ludo/src/guix-past/modules/past/packages/maths.scm.go ;;; note: source file /home/ludo/src/guix-past/modules/past/packages/perl.scm ;;; newer than compiled /gnu/store/6b0ww9dxvfig7wdxqcyjs0hlw331la4z-guix-past/lib/guile/3.0/site-ccache/past/packages/perl.go ;;; found fresh local cache at /home/ludo/.cache/guile/ccache/3.0-LE-8-4.3/home/ludo/src/guix-past/modules/past/packages/perl.scm.go ;;; note: source file /home/ludo/src/guix-past/modules/past/packages/python.scm ;;; newer than compiled /gnu/store/6b0ww9dxvfig7wdxqcyjs0hlw331la4z-guix-past/lib/guile/3.0/site-ccache/past/packages/python.go ;;; note: source file /home/ludo/src/guix-past/modules/past/packages/python.scm ;;; newer than compiled /home/ludo/.cache/guile/ccache/3.0-LE-8-4.3/home/ludo/src/guix-past/modules/past/packages/python.scm.go ;;; note: source file /home/ludo/src/guix-past/modules/past/packages/statistics.scm ;;; newer than compiled /gnu/store/6b0ww9dxvfig7wdxqcyjs0hlw331la4z-guix-past/lib/guile/3.0/site-ccache/past/packages/statistics.go ;;; note: source file /home/ludo/src/guix-past/modules/past/packages/simgrid.scm ;;; newer than compiled /gnu/store/6b0ww9dxvfig7wdxqcyjs0hlw331la4z-guix-past/lib/guile/3.0/site-ccache/past/packages/simgrid.go ;;; found fresh local cache at /home/ludo/.cache/guile/ccache/3.0-LE-8-4.3/home/ludo/src/guix-past/modules/past/packages/simgrid.scm.go ;;; note: source file /home/ludo/src/guix-past/modules/past/packages/web.scm ;;; newer than compiled /gnu/store/6b0ww9dxvfig7wdxqcyjs0hlw331la4z-guix-past/lib/guile/3.0/site-ccache/past/packages/web.go /gnu/store/nah91czddjcb72ghx9kh2z6jwad0kh4d-autoconf-2.59 --8<---------------cut here---------------end--------------->8--- The problem as can be seen above is that all these Guile warnings are confusing at best and useless: there’s nothing the user can do about them. Ludo’.