I've been hiring part-time engineers for about 2 years now at my consulting company. I post on r/Jobs4Bitcoins, ask for their github and that they speak English fluently.
I have some really good engineers who love working for me. I do weekly standups, give them direction and then get the f-- out of their way.
We have a kanban board where I populate tasks and the devs just grab what they want to work on. We don't do sprints.