For openSUSE Tumbleweed run the following as root:
zypper addrepo https://download.opensuse.org/repositories/home:jloehel:dradis/openSUSE_Tumbleweed/home:jloehel:dradis.repo
zypper refresh
zypper install rubygem-rake-compiler
For openSUSE Factory ARM run the following as root:
zypper addrepo https://download.opensuse.org/repositories/home:jloehel:dradis/openSUSE_Factory_ARM/home:jloehel:dradis.repo
zypper refresh
zypper install rubygem-rake-compiler
For 15.6 run the following as root:
zypper addrepo https://download.opensuse.org/repositories/home:jloehel:dradis/15.6/home:jloehel:dradis.repo
zypper refresh
zypper install rubygem-rake-compiler
For 15.5 run the following as root:
zypper addrepo https://download.opensuse.org/repositories/home:jloehel:dradis/15.5/home:jloehel:dradis.repo
zypper refresh
zypper install rubygem-rake-compiler