When comparing NixOS vs Slax, the Slant community recommends NixOS for most people. In the question“What are the best Linux distributions for desktops?” NixOS is ranked 19th while Slax is ranked 54th. The most important reason people chose NixOS is:
Atomic non-destructive upgrades / rollback of a system upgrade / declarative reproducible system configuration / unprivileged installation of packages / transparent source or binary deployment.
Specs
Ranked in these QuestionsQuestion Ranking
Pros
Pro State of the art package manager
Atomic non-destructive upgrades / rollback of a system upgrade / declarative reproducible system configuration / unprivileged installation of packages / transparent source or binary deployment.
Pro Minimal
You can start with a minimal environment and add packages and software to suit your needs as you go along.
Pro Reproducible system
NixOS is configured using the Nix package manager, allowing your system to be replicated and kept in sync across multiple machines. Great for keeping a laptop and desktop in sync.
Pro Robust
Packages don't break after a NixOS upgrade as they are prone to with other distros (especially Arch).
Pro Persistent changes
Changes you make in the configuration persist if you run from USB.
Pro Pretty fast to boot up
It was considerably fast to turn on when booting from cd.
Pro Modules
Standard tar archives plus some simple shell scripting produces modules that you can load dynamically into the OS for added apps and functionality.
Pro Modern desktop
Pro Small footprint
About 200mb, but with a full KDE4 environment and loads of useful apps.
Cons
Con Documentation is not good
A lot of the documentation of various functions is buried on the source code, their respective manuals, or non-existent. The documentation, the conventions, and the scattered toolchain really made searching for stuff easily missable.
Con A configuration change might end up bricking your system
Con Overly complicated HDD/SSD installation
While it has a nice layout Slax's lack of an installer tool like Tinycore's just can't be justified. It seems strange that it comes built in with programs that some users may not want, yet it doesn't have an easy way to install it. Due to its heavier use of RAM, built in software, and lack of an installer its hard to choose it over TC.
Con Works slowly on old computers
Con Infrequent releases
Since Slax is maintained by only one person, releases are not that frequent. So it may take a while to get bug fixes or new features once you start using it.