In the weekly build scripts, the spack mirror create command in 04_SpackInstall.sh does not have the correct behavior when installing only a subset of the environment's root specs. In particular, even though the unified-dev template specs 'ufs-weather-model ^[email protected]', spack mirror create, at least on Acorn, is fetching [email protected] instead. This is true even when I specify only ufs-weather-model or ufs-weather-model ^[email protected] for the arguments to spack mirror create. For now I intend to work around it by adding the option to disable fetching there, then I'll use spack fetch as part of Acorn's spack_install_wrapper(), but I'll leave this issue here for discussion in case anyone else is affected. For anyone using the default --all (maybe we should have an option for fetching all even if not all packages will be installed?), this shouldn't be a problem. I don't know if anyone else plans to only install a subset of unified-dev.