Hi Léo, I've committed this, with minor changes, as c53ee79c4ce187b185a070977f69ad9d4fb55179. Léo Le Bouter writes: > + (add-after 'install 'install-credential-libsecret > + (lambda* (#:key outputs #:allow-other-keys) > + (let* ((libsecret (assoc-ref outputs "credential-libsecret"))) > + (with-directory-excursion "contrib/credential/libsecret" > + ((assoc-ref gnu:%standard-phases 'build)) > + (install-file "git-credential-libsecret" > + (string-append libsecret "/bin")))))) A few days ago, I tested your patch (applied to 19783b9f553e433743fd695302df8cac4ec91ae1, which at the time was the latest commit on master). Unfortunately, it caused git-minimal to fail to build: --8<---------------cut here---------------start------------->8--- ./pre-inst-env guix build git ... starting phase `install-credential-libsecret' make: pkg-config: No such file or directory make: pkg-config: No such file or directory gcc -g -O2 -o git-credential-libsecret.o -c git-credential-libsecret.c git-credential-libsecret.c:29:10: fatal error: glib.h: No such file or directory #include ^~~~~~~~ compilation terminated. make: *** [Makefile:19: git-credential-libsecret.o] Error 1 command "make" "-j" "2" failed with status 2 builder for `/gnu/store/fwfv6k7jl8f77awgvs0lg3dnlx85nxd9-git-minimal-2.30.1.drv' failed with exit code 1 build of /gnu/store/fwfv6k7jl8f77awgvs0lg3dnlx85nxd9-git-minimal-2.30.1.drv failed View build log at '/var/log/guix/drvs/fw/fv6k7jl8f77awgvs0lg3dnlx85nxd9-git-minimal-2.30.1.drv.bz2'. guix build: error: build of `/gnu/store/fwfv6k7jl8f77awgvs0lg3dnlx85nxd9-git-minimal-2.30.1.drv' failed --8<---------------cut here---------------end--------------->8--- The same command (./pre-inst-env guix build git) succeeded on commit 19783b9f553e433743fd695302df8cac4ec91ae1. The problem was that git-minimal inherits the arguments (thus the phases) from git, so it needs to also delete the newly added phase: (delete 'build-subtree) (delete 'split) (delete 'install-man-pages) (delete 'install-subtree) (delete 'install-credential-netrc) (delete 'install-credential-libsecret) I also took the liberty of adding #t at the end of the new phase. My understanding is that all successful phases should still be returning #t, as described below, so please take care to always return #t at the end of every phase: https://lists.gnu.org/archive/html/guix-devel/2018-01/msg00353.html https://lists.gnu.org/archive/html/guix-devel/2018-05/msg00369.html Thank you for the contribution! I hope it streamlines your workflow! -- Chris