The default fan control firmware works, but when doing long builds and such, the CPU temperature can hit 80C, which is higher than I like to see. So one approach is to use a semi-automatic method: set the min/max fan speed values that the firmware pays attention to, such that the temperature is kept lower than the default. (If you just set the min fan speed slightly higher, it will make an unnecessary amount of noise when the machine is idle, and still won't keep it cool enough during heavy lifting.)

[https://wiki.ubuntu.com/MacBookPro/SantaRosaFanControl This script] works with Gentoo on the Mac Mini with some modifications: