Er, upgrading ArchLinux via Dockerfile? idk.

Dockerfile

FROM base/archlinux

RUN pacman --noconfirm -S --needed archlinux-keyring     && \
    pacman --noconfirm -S --needed openssl pacman        && \
    pacman-key --init                                    && \
    pacman-key --populate archlinux                      && \
    pacman-key --refresh-keys                            && \
    pacman-db-upgrade                                    && \
    pacman --noconfirm -Syy                              && \
    pacman --noconfirm -S --needed archlinux-keyring     && \
    pacman --noconfirm -S --needed openssl pacman        && \
    pacman-db-upgrade                                    && \
    pacman --noconfirm -Suu                              && \
    pacman --noconfirm -Rns $(pacman -Qdttq)             && \
    pacman --noconfirm -Scc                              && \
    pacman-optimize                                      && \
    find /etc/ -type f -name '*.pac*' -exec rm {} \;     && \
    rm -rf /var/cache/pacman/pkg/*