apt-get install -y autoconf make gcc
Reference : https://blog.packagist.com/composer-2-0-is-now-available/ Download using wget and then replace the existing composer command inside the bin folder
wget https://raw.githubusercontent.com/composer/getcomposer.org/76a7060ccb93902cd7576b67264ad91c8a2700e2/web/installer -O - -q | php -- --quiet