postgres

I never use it for databases. I find I don’t gain much from containerizing it, because the interesting and difficult bits of customizing and tayloring a database to your needs are on the data file system or in kernel parameters, not in the database binaries themselves. On most distributions it’s trivial to install the binaries for postgres/mariadb or whatnot.

Databases are usually fairly resource intensive too, so you’d want a separate VM for it anyway.