Break out of circular dependency in workstation build

Containerfile

@@ -6,12 +6,21 @@ ARG FACTER_makeopts
 ARG PROFILE
 
 RUN eix-sync -q
+
+# Set up some conveniences
 RUN FACTER_build=stage1 puppet agent --test --certname ci --environment main --tags nest::base::distcc,nest::base::portage,nest::base::puppet --logdir /var/log/puppet --rundir /var/run/puppet --vardir /var/lib/puppet --runtimeout 0; [ $? -eq 2 ]
+
+# Switch to desired profile and make the base system consistent with it,
+# breaking out of a possible circular dependency between mesa and libva.
 RUN eselect profile set "nest:${PROFILE}"
 RUN emerge --info
+RUN USE='-vaapi' emerge -v --update --deep --newuse --with-bdeps=y @world
 RUN emerge -v --update --deep --newuse --with-bdeps=y @world
 RUN emerge --depclean
+
+# Configure the stage
 RUN FACTER_build=stage1 puppet agent --test --runtimeout 0; [ $? -eq 2 ]
+
 RUN rm -rf /var/db/repos
 
 CMD ["/bin/zsh"]