I presume you mean site reliability engineer. Then yes, my clients purchase the whole package. Development, deployment, hosting, production maintenance. So if something goes wrong, really anything, I'm their first point of contact.

Before, we had many situations where they asked me to take a look because something could have been a software issue but then turned out to be an AWS issue instead. That's always nasty if I need to tell my client "sorry you're offline, try calling Amazon". Even if they understand that there's nothing I can do, emotionally they still feel disappointed in me. When I use my own infrastructure, I can avoid these situations because it's in my power to make the necessary hosting repairs, too.

I've always found it interesting how simply "Not Megacorporation X" can be a competitive advantage. It doesn't make a lot of economic sense, but people will go through a lot of work - and it can be lucrative to you on the business-side facilitating this - to avoid having to interface with a faceless conglomerate like Amazon.

For my customers, it does make A LOT of economic sense. The financial damage from being offline for a few hours and unable to reach any support person at your hosting company is very much real.

At their spending level, "Megacorporation X" would not pick up the phone for them. But I do. So in effect, my competitive advantage is not that I'm not a megacorp, but my competitive advantage is that I pick up the phone when they call.