CRUX is a lightweight, x86-64-optimized Linux distribution targeted at experienced Linux users and delivered by a tar.xz-based package system with BSD-style initscripts. It is not based on any other Linux distribution. It also utilizes a ports system to install and upgrade applications.
CRUX does not include a GUI installation program. Instead, the user boots the kernel stored on either a CD or diskette; partitions the hard disk drive(s) to which the operating system will be installed (using a program such as fdisk or cfdisk); creates the appropriate file systems on the various partitions; mounts the CD or NFS share along with the partitions made previously for use by the package installation script; compiles a new kernel; and installs a bootloader, all via shell commands.
CRUX implements an infrastructure similar to that of BSD-based operating systems for package management. Packages consist of a Pkgfile (which is a shell script), any patches required to adjust the program to work, md5sum hashes used to verify the integrity of the downloaded files and a footprint file listing the files to be included in the packages. These files are downloaded from a CRUX software repository, compiled, and installed using the prt-get frontend to pkgutils. The software sources are downloaded from the websites of their respective upstream at the address specified in the Pkgfile.