The following packages are included by default on a fresh DigitalOcean droplet using Debian 9.3 (stretch):
adduser/now 3.115 all [installed,local]
apt/now 1.4.8 amd64 [installed,local]
apt-utils/now 1.4.8 amd64 [installed,local]
aptitude/now 0.8.7-1 amd64 [installed,local]
aptitude-common/now 0.8.7-1 all [installed,local]
base-files/now 9.9+deb9u3 amd64 [installed,local]
base-passwd/now 3.5.43 amd64 [installed,local]