Hi, I encountered a similar error message today, but it worked fine after retrying. After digging around in /var/log/guix/drvs, I found these lines in an appropriately-timestamped log file: substitute: guix substitute: warning: ci.guix.gnu.org: connection failed: Connection timed out @ build-started /gnu/store/klyq05c1q8jzwnwrlmvy4ma6m2h6hbk0-compute-guix-derivation.drv - x86_64-linux /var/log/guix/drvs/kl//yq05c1q8jzwnwrlmvy4ma6m2h6hbk0-compute-guix-derivation.drv.bz2 3907994 @ build-succeeded /gnu/store/klyq05c1q8jzwnwrlmvy4ma6m2h6hbk0-compute-guix-derivation.drv - I do recall seeing the Connection timed out message, I'd even say it's probably the reason why I decided to retry the pull without much investigation. Regards, Jakub Kądziołka