SQLite doesn't have all the conveniences of Oracle products or DB2 so that is not a good analogy.
I'd define a minimal working system as the distro's MTA set up to BE a smarthost instead of set up to USE a smarthost which is usually not much, and an imap server so "normal" non-mutt using endusers can access it.
Everything else is bolt on fun once that basic setup works. Client side spam filtering gets you out of being the middleman, which is awesome if you'd be stuck as the middleman.
There's nothing wrong with the article as a display of nearly the largest most complicated system you can design, which is perfectly cool and fun. Personally I'd add commentary to the article about load balancing and proxying and DNS needs more than "yup gonna have to do DNS" but it is very near a maxed out design.
Many HN comments are along the lines of "this maxed out design is large and complicated which implies ..." However That doesn't imply anything about non-maxed out designs. The level of what can be accomplished in (insert programming language) in a maximally complicated situation doesn't necessarily imply much about the difficulty of "hello world"
Exim and a simple dovecot imap are about ten lines of config editing total. It won't do much, but sometimes that exactly what is needed.
I'd define a minimal working system as the distro's MTA set up to BE a smarthost instead of set up to USE a smarthost which is usually not much, and an imap server so "normal" non-mutt using endusers can access it.
Everything else is bolt on fun once that basic setup works. Client side spam filtering gets you out of being the middleman, which is awesome if you'd be stuck as the middleman.
There's nothing wrong with the article as a display of nearly the largest most complicated system you can design, which is perfectly cool and fun. Personally I'd add commentary to the article about load balancing and proxying and DNS needs more than "yup gonna have to do DNS" but it is very near a maxed out design.
Many HN comments are along the lines of "this maxed out design is large and complicated which implies ..." However That doesn't imply anything about non-maxed out designs. The level of what can be accomplished in (insert programming language) in a maximally complicated situation doesn't necessarily imply much about the difficulty of "hello world"
Exim and a simple dovecot imap are about ten lines of config editing total. It won't do much, but sometimes that exactly what is needed.