[johngalt]

Depends on the nature of the work. Begin with the understanding that operational concerns will never be zero hours. The best freelancer in the world will need guidance from the internal staff.

If you've already got something in place and operating at <10 hours a week, I'd keep it in house with whatever dev has more ops experience. Or whichever one drew the short straw after no one admits to having ops experience. You could hand it off to your newer hires to gain an understanding of what you do. The key is to define who responds to what.

Keep an engineer on retainer that you can call in to handle one-off builds and emergencies. Big changes/deployments where you can't afford to gain experience the hard way.