Hi Ludo’! Could you please take a look at the bug report ? There are two reproducible problems when building the guix-1.2.0 package. There is a patch already for the first of the two problems (an incomplete cleanup) at . For the other issue with a wrong path "dtmp/guix-tests/store/", there is a summary at . This problem is existing since years and seems to be depending on the underlying file-system. It seems to appear with a tmp-store on a unionfs-fuse or NFS. In the past it got hidden by switching to overlayfs or changes on the NFS server side. As the CI for aarch64 is always lagging behind these issues are kind of blockers to me. Today they block the build of guix-1.2.0-8.7624ebb. Bye Stefan