In order to play The Long Dark on macOS with maximum graphics settings, you need a computer with a configuration no worse than the following
Operating System:
OSX 10.9.3
Processor (CPU):
Core i7 @ 2.7GHz+
Memory (RAM):
8 GB RAM
Graphics Card:
Dedicated standalone GPU w/ 1GB+ VRAM
Storage:
7 GB available space
Sound Card:
On-board