The Linux distribution NixOS makes changes risk-free with sophisticated rollback capabilities. Version 22.05 updates many packages.
The developers of the slightly different Linux -Distribution NixOS have updated the substructure in the now released version 22.05 (codename Quokka). Distribution users should update soon: Support for NixOS 21.11 ends at the end of June, the new version 22.05 should be supported until the end of December.
NixOS is based on the eponymous package manager Nix, which does not overwrite anything, but every change or customization considered as a new package. Any failed updates can therefore not endanger the system and can be easily reversed.
The log of changes in NixOS 22.05 is quite long. The highlights include updating the Gnome desktop to version 42, PHP is available in version 8.1. Since the old Mattermost version has reached the end of support, the developers have now included version 6.3. Other current software packages include PostgreSQL in version 14, Systemd in the almost current version 250 and Pulseaudio 15.0, which now supports the Bluetooth codecs aptX and LDAC.
There are also numerous new services on board. Rootless Docker is now available. PostgreSQL databases can be managed with the supplied pgadmin4. IRC servers and support tools are included in the collection. The apfs module allows access to drives formatted with the current macOS. The list is too extensive and can be found in the changelog linked above.
Administrators will also find a list of possible incompatibilities with previous NixOS versions there. However, these are relatively special. There are changes that affect the cross-compiling of Haskell packages. The configuration and status directories from nixos-containers had to be moved to libcontainer-based software like Podman or Skopeo for compatibility reasons. Instead of being in /etc/containers and /var/lib/containers, they are now under /etc/nixos-containers and /var/lib/nixos-containers. In addition, security.klogd was thrown out, since systemd now takes over the logging of kernel messages.
The changelog lists other changes worth mentioning. Those who want to switch should check the long list of changes to see whether the software they use is affected by the changes.
The current installation packages can be found on the NixOS download page. The NixOS makers recommend the Live CD image with the Gnome desktop for most users. There is also a version with the KDE Plasma desktop or a much smaller version without a graphical user interface, which is controlled via the command line and also contains numerous rescue tools.