This blog outlines installation of OpenBSD 6.0 alongside macOS using the native boot loader. Pre-install Tasks First download a disk image of 64-bit OpenBSD installer(installXX.fs) from OpenBSD site and write it to a USB drive. $ sudo dd if=Downloads/install60.fs of=/dev/disk2 bs=1m Broadcom wireless chips used in MacBook lacks a driver in OpenBSD. I used TP-LINK TL-WN725N USB wireless adapter. Download the urtwn firmware from OpenBSD site Now we will mount the EFI partition and copy the firmware file downloaded to it. $ sudo mkdir /Volumes/efi $ sudo mount -t msdos /dev/disk0s1 /Volumes/efi $ sudo cp urtwn-firmware-1.2.tgz /Volumes/efi/ Now we will create two HFS partitions using the Disk Utility application in macOS.