Everyone is software engineer, some of which happens to do HR, marketing, sales, recruiting ...
Small team. Move fast. Automate as many things as possible (software is eating the world ...)
I know, this is kind of idealism. But, seriously, any success example?
"Ask accountingnews: Is it possible to build an accounting firm where everyone is an accountant?"
"Ask shockedhackers: Is it possible to build an electrical business where everyone is an electrician?"
"Ask housebuilders: Is it possible to build a home construction business where everyone is a carpenter?"
etc.
At some very very small scale, sure, but usually it's because of necessity, not because it's a good way to do things. Specialization is awesome! Having people in your company that are very very good at particular aspects of your business is a huge advantage over all the poor saps that are trying to wing it with a bunch of folks that don't really know what they're doing when it comes to marketing, sales, design, copywriting, accounting, law...