-raspi_root/: raspi_root .FORCE
- printf '${SOURCES}' >$@/etc/apt/sources.list
- -chroot "$@" apt-key add - <./raspberrypi-archive-keyring.gpg
+norecommends: raspi_root/etc/apt/apt.conf.d/10norecommends
+raspi_root/etc/apt/apt.conf.d/10norecommends: raspi_root
+ mkdir -p "$</etc/apt/apt.conf.d/"
+ printf 'APT::Install-Recommends "false";\n' >"$@"
+ chmod 644 "$@"
+
+apt_keys: raspi_root
+ -chroot "$<" apt-key add - <./raspbian-archive-keyring.gpg
+ -chroot "$<" apt-key add - <./raspberrypi-archive-keyring.gpg
+ -chroot "$<" apt-key add - <./debian-archive-stretch-stable.gpg
+
+raspi_root/: raspi_root norecommends apt_keys .FORCE
+ printf %s "$$SOURCES" >$@/etc/apt/sources.list