CRUX is a DIY distribution that is perhaps less know than others, but it is the inspiration behind the mighty Arch Linux as the distribution Judd Vinet was originally using.
The intro on the main page states that "CRUX is a lightweight, i686-optimized Linux distribution targeted at experienced users", and I would suggest to take this seriously. It's unlike installing Linux MInt or Fedora, it's not even like installing a modified Gentoo, more somewhere between Gentoo or Linux from Scratch and Slackware, with the latter being the easy one. Like most advanced distributions CRUX aims at keeping it simple, adhering to the KISS philospohy. For that it uses a straightforward tar.gz-based package system and BSD-style initscripts, again similar to Slackware and Arch for example. The system is configured through manually editing text files. The main repository as small and provides few packages, but users have access to a ports system which suposedly "makes it easy to install and upgrade applications". We'll see how that works, but personally I think this sounds great. If you like something with a similar outlook to Slackware, perhaps a bit more rolling but not quite as much as Arch and not foisting systemd on you just yet, with a BSD-style ports tree then this could be for you. Actually, a lot of the more advanced Linux distributions seem to be modelling themselves on the BSD's in this respect. It's basically a repository with source code that compiles for your machine at install time.