To allow Guix to download substitutes from
ci.guix.gnu.org or a
mirror thereof, you
must add its public key to the access control list (ACL) of archive
imports, using the
guix archive command (see Invoking guix archive). Doing so implies that you trust
ci.guix.gnu.org to not
be compromised and to serve genuine substitutes.
The public key for
ci.guix.gnu.org is installed along with Guix, in
prefix/share/guix/ci.guix.gnu.org.pub, where prefix is
the installation prefix of Guix. If you installed Guix from source,
make sure you checked the GPG signature of
guix-1.1.0.tar.gz, which contains this public key file.
Then, you can run something like this:
# guix archive --authorize < prefix/share/guix/ci.guix.gnu.org.pub
Once this is in place, the output of a command like
should change from something like:
$ guix build emacs --dry-run The following derivations would be built: /gnu/store/yr7bnx8xwcayd6j95r2clmkdl1qh688w-emacs-24.3.drv /gnu/store/x8qsh1hlhgjx6cwsjyvybnfv2i37z23w-dbus-1.6.4.tar.gz.drv /gnu/store/1ixwp12fl950d15h2cj11c73733jay0z-alsa-lib-18.104.22.168.tar.bz2.drv /gnu/store/nlma1pw0p603fpfiqy7kn4zm105r5dmw-util-linux-2.21.drv …
to something like:
$ guix build emacs --dry-run 112.3 MB would be downloaded: /gnu/store/pk3n22lbq6ydamyymqkkz7i69wiwjiwi-emacs-24.3 /gnu/store/2ygn4ncnhrpr61rssa6z0d9x22si0va3-libjpeg-8d /gnu/store/71yz6lgx4dazma9dwn2mcjxaah9w77jq-cairo-1.12.16 /gnu/store/7zdhgp0n1518lvfn8mb96sxqfmvqrl7v-libxrender-0.9.7 …
The text changed from “The following derivations would be built” to
“112.3 MB would be downloaded”. This indicates that substitutes from
ci.guix.gnu.org are usable and will be downloaded, when
possible, for future builds.
The substitute mechanism can be disabled globally by running
--no-substitutes (see Invoking guix-daemon). It can also be disabled temporarily by passing the
--no-substitutes option to
build, and other command-line tools.