The tool currently relies on Linux specific sysfs paths (e.g., /sys/class/thermal) and modprobe. For FreeBSD support, research how to read CPU frequency, temperature, and power using sysctl (e.g., dev.cpu.0.freq, hw.acpi.thermal.tz0.temperature) and possibly the coretemp kernel module. Examine existing comments in the issue for alternative approaches and test on a FreeBSD system. The main file to modify is likely src/s tui/s tui.py or a backend module that interfaces with the OS.
