Welcome to the Raring Ringtail edition of Ubuntu Core, a special Ubuntu project that delivers a minimal root filesystem to advanced users with special requirements who want to build and deploy custom versions of the world's most popular free operating system.
Availability, supported architectures
Ubuntu Core 13.04 was officially announced by Canonical on April 25, 2013 and supported until January 27, 2014. It can still be downloaded from our website as tar archives for the 32-bit (i386), 64-bit (amd64), ARM Hard Float (ARMhf) and PowerPC (PPC) instruction set architectures.
Ubuntu Core usage instructions
To build a custom Ubuntu-based operating system, you'll first need to download the Ubuntu Core tar archive for your target architecture, as well as a Linux kernel package and a boot loader. Prepare a partition on the target device and format it with a stable and supported Linux file system, like EXT4, EXT3 or EXT2.
Extract the contents of the Ubuntu Core package on the Linux partition that you've just formatted, extract, compile and install the Linux kernel archive, and extract and install the boot loader. In addition, it is possible to add extra modules to the Linux kernel in the /lib/modules/$(uname -r) folder.
That's it! To see if the system works, boot the target device. If everything works, you can start installing additional packages with the apt-get command. Only your imagination is the limit of what it is possible to create with Ubuntu Core.
Summing up, Ubuntu Core 13.04 proves to be a popular project among advanced Linux users who are looking for a hassle-free solution to build and deploy custom Ubuntu-based OSes on server, desktop or embedded machines. Keep in mind though, that this release is no longer maintained and has been archived for historical purposes only.