liveusb-builder is a script suite to create multiboot USB stick for GNU/Linux distributions. It's lightweight with few dependencies, and it's extensible and hackable.

The source code is hosted on both git.wehack.space and GitHub.

A presentation in Chinese is at https://wehack.space/vimacs/liveusb-builder.odp.

• Multiboot support with syslinux and GRUB
• Support placing kernel files (kernel and initramfs) and other data files (squashfs, CD image) in separate partitions
• Download an up-to-date CD image and verify it
• A GNU/Linux command line tool

You need these packages on your GNU/Linux system to use liveusb-builder.

• udevil: for mounting iso files
• wget: for downloading
• syslinux (recommended): bootloader for legacy BIOS
• GRUB: bootloader for leagacy BIOS if there's no syslinux, and bootloader for UEFI

For Arch Linux users, just install liveusb-builder-git from AUR.

First mount your USB drive partition. I recommend using udevil so that you can write files without as root.

Then run buildlive script as follows, suppose your USB is /dev/sdb and /dev/sdb1 is mount to /media/sdb1:

# install Arch, Mint (x86_64 with MATE Desktop) and Fedora 28 to USB
./buildlive --root=/media/sdb1 arch mint/64/mate fedora/28

Partition your disk as follows to create a 500MB FAT32 boot partition, and an ext2 partition using the remaining space, suppose your USB is /dev/sdb.

$ sudo fdisk /dev/sdb

Command (m for help): o
Created a new DOS disklabel with disk identifier 0x24c5dd70.

Command (m for help): n
Partition type
   p   primary (0 primary, 0 extended, 4 free)
   e   extended (container for logical partitions)
Select (default p):

Using default response p.
Partition number (1-4, default 1):
First sector (2048-30463999, default 2048):
Last sector, +sectors or +size{K,M,G,T,P} (2048-30463999, default 30463999): +500M

Created a new partition 1 of type 'Linux' and of size 500 MiB.

Command (m for help): t
Selected partition 1
Hex code (type L to list all codes): b
Changed type of partition 'Linux' to 'W95 FAT32'.

Command (m for help): a
Selected partition 1
The bootable flag on partition 1 is enabled now.

Command (m for help): n
Partition type
   p   primary (1 primary, 0 extended, 3 free)
   e   extended (container for logical partitions)
Select (default p):

Using default response p.
Partition number (2-4, default 2):
First sector (1026048-30463999, default 1026048):
Last sector, +sectors or +size{K,M,G,T,P} (1026048-30463999, default 30463999):

Created a new partition 2 of type 'Linux' and of size 14 GiB.

Command (m for help): w
The partition table has been altered.
Calling ioctl() to re-read partition table.
Syncing disks.

Format the partitions:

sudo mkfs.msdos -F 32 /dev/sdb1
sudo mkfs.ext2 /dev/sdb2

Mount them and create the directory, and we need to make the directory liveusb-data writable by the current user.

udevil mount /dev/sdb1 /media/boot
udevil mount /dev/sdb2 /media/root
sudo install -d /media/root/liveusb-data
sudo chown $(whoami) /media/root/liveusb-data/

At last, make the Live USB (we install Arch and Fedora 28 in it):

$ ./buildlive --boot /media/boot --root /media/root arch fedora/28

The resulting USB stick works on QEMU with PC BIOS (SeaBIOS), UEFI (OVMF), libreboot (i440fx, GRUB txtmode) as firmware.

You can search keyword multiboot on GitHub and find some related projects. Listed below is some related work I know or find.

• Yumi: a Windows GUI multiboot USB builder, I need a similar tool that runs on GNU/Linux, so I created this project
• aguslr/multibootusb: provides grub.cfg files for many CD images, I used some of the kernel command line of distros in this project, but some grub.cfg files use features provided by GRUB and thus not portable for loaders like syslinux
• MultiBootLiveUSB
• Multiboot USB drive - ArchWiki
• cbodden/multiboot
• mbusb/multibootusb