smartmontools is available in latest CentOS repositories so it will likely be updated in next release of XCP-ng which will use updated CentOS packages. It's also available in our repository for testing updated CentOS packages with XCP-ng:

If you don't want to take the risky route, just add the test repository by downloading the .repo file, then edit it to disable xcp-ng-centos_testing by default, and then use it only for installing the updated smartmontools with:

yum update smartmontools --enablerepo='xcp-ng-centos_testing'

nvme-cli is not available in that repository, but it is from CentOS: and I added it to the wishlist at

olivierlambert created this issue in xcp-ng/xcp open List of useful extra packages for dom0 #56