function _ddev() {
    cache="/tmp/${FUNCNAME[0]}"

    if ! [ -f "$cache" ]; then
        curl -sfL 'https://api.github.com/repos/docker-library/official-images/git/trees/master?recursive=1' | sed -nE 's/.*"library\/(.+)",$/\1/p' > "$cache"
    fi
    [ "$COMP_CWORD" -ne 1 ] && return
    mapfile -t COMPREPLY < <(compgen -W "$(cat "$cache")" -- "${COMP_WORDS[1]}")
}
complete -F _ddev ddev