For systems without CD drive, the NixOS live CD can be booted from a USB stick. You can use the dd utility to write the image: dd if=path-to-image of=/dev/sdX. Be careful about specifying the correct drive; you can use the lsblk command to get a list of block devices. $ diskutil list [..] /dev/diskN (external, physical): #: TYPE NAME SIZE IDENTIFIER [..] $ diskutil unmountDisk diskN Unmount of all volumes on diskN was successful $ sudo dd bs=1m if=nix.iso of=/dev/rdiskN Using the 'raw' rdiskN device instead of diskN completes in minutes instead of hours. After dd completes, a GUI dialog "The disk you inserted was not readable by this computer" will pop up, which can be ignored. The dd utility will write the image verbatim to the drive, making it the recommended option for both UEFI and non-UEFI installations.