Hello, On a machine configured with 20 builders: --8<---------------cut here---------------start------------->8--- (guix-service-type config => (guix-configuration (inherit config) (build-accounts 20) (discover? #t) (log-compression 'none) (extra-options '("--max-jobs=20")))) --8<---------------cut here---------------end--------------->8--- Running 'guix package -m manifest.scm' with hundreds of packages/MiB to fetch from the substitute servers, it fails like: --8<---------------cut here---------------start------------->8--- $ guix package -m ~/stow/guix/manifest.scm -M7 The following packages will be installed: acpi 1.7 adb 7.1.2_r36 adwaita-icon-theme 40.1.1 alsa-utils 1.2.4 ansible 4.7.0 anthy 9100h arc-icon-theme 20161122 arc-theme 20210412 [...] xournal 0.4.8.2016 xrandr 1.5.1 xrdb 1.2.1 xsetroot 1.1.2 yelp 41.0 substitute: updating substitutes from 'https://ci.guix.gnu.org'... 100.0% substitute: updating substitutes from 'https://bordeaux.guix.gnu.org'... 100.0% 924.3 MB will be downloaded substitution of /gnu/store/1w54x244cykra3p2bmmxv9jn12q92l0r-gimp-2.10.32-doc complete [...] substitution of /gnu/store/adq43ck5b12sx0n9hy4hgay4gk7spy5b-libxml++-2.40.1 complete substitution of /gnu/store/i379f1vadva2lnk1jh60c03s26m6rj7b-ibus-1.5.24-doc complete substitution of /gnu/store/9j1hfzgpllgshy6qn82pl8zkkgn4058w-hackneyed-x11-cursors-0.8.2 complete substitution of /gnu/store/bl9y57k0wg3aqxb8xiwddagj3i4dk036-perl-b-hooks-endofscope-0.24 complete substitution of /gnu/store/qpc614b2hbzcsjhac38m9av3cqnrwjqi-perl-datetime-1.54 complete substitution of /gnu/store/r07xvd187my02gg5smlw4pis90x7m3ah-opensp-1.5.2 complete guix substitute: warning: while fetching https://ci.guix.gnu.org/nar/lzip/q7hiikl3q3dk1r46rlyyzd90yaddydrd-gnucash-docs-4.10: server is somewhat slow guix substitute: warning: try `--no-substitutes' if the problem persists guix substitute: error: connect*: Connection timed out substitution of /gnu/store/q7hiikl3q3dk1r46rlyyzd90yaddydrd-gnucash-docs-4.10 failed guix package: error: corrupt input while restoring archive from socket --8<---------------cut here---------------end--------------->8--- It fails like the above when the number of jobs is 6 or higher, but proceeds without error when the number of jobs is 5 or less. I do not think the network to be at caused, as everything is cabled and the link is healthy and fast. Thanks, Maxim