Low tech as long as the temps at night are at least mid to low 40F’s, same as a refrigerator:
Gut, skin and bag the beast ASAP. Whole or in pieces is fine.
Get it to a local cooler if possible. Otherwise…
Hang to let cool and dry.
Protect it from sun, rain and/or heavy fog with an overhead & side tarp/very loose water proof bag.
Let the bag(s) be exposed to the open air in the late evening and night.
In the early morning, insulate the carcass with a sleeping bag/heavy blanket as much as possible.
Remove sleeping bag/blanket and let it re-cool the next evening & night. Repeat the last 2 steps as needed.
I’ve used this method with deer and elk for as long as 10 days. It works even if the meat freezes at lower overnight temps.