I worked at a small unicorn (~150 engineers when I started, 400 when I left) several years ago; we ran our own Github Enterprise solely for this reason. It was

I worked at a small unicorn (~150 engineers when I started, 400 when I left) several years ago; we ran our own Github Enterprise solely for this reason. It was a pain in the ass to set-up, but mostly hand-off to keep it running. I think we had roughly one degradation event a year (something went wrong with an update), and they were brief.