In addition to numerous new and upgraded packages, this release has the following highlights: Firefox and similar browsers are now wrapped by default. The package and attribute names are plain firefox or midori, etc. Backward-compatibility attributes were set up, but note that nix-env -u will not update your current firefox-with-plugins; you have to uninstall it and install firefox instead. More discussion is on the PR. The following new services were added since the last release: services/monitoring/longview.nix services/networking/pdnsd.nix services/web-apps/pump.io.nix services/security/haka.nix i18n/inputMethod/default.nix When upgrading from a previous release, please be aware of the following incompatible changes: wmiiSnap has been replaced with wmii_hg, but services.xserver.windowManager.wmii.enable has been updated respectively so this only affects you if you have explicitly installed wmiiSnap. jobs NixOS option has been removed. It served as compatibility layer between Upstart jobs and SystemD services. All services have been rewritten to use systemd.services wmiimenu is removed, as it has been removed by the developers upstream. Use wimenu from the wmii-hg package. Gitit is no longer automatically added to the module list in NixOS and as such there will not be any manual entries for it. You will need to add an import statement to your NixOS configuration in order to use it, e.g. ]; } ]]> will include the Gitit service configuration options. nginx does not accept flags for enabling and disabling modules anymore. Instead it accepts modules argument, which is a list of modules to be built in. All modules now reside in nginxModules set. Example configuration: s3sync is removed, as it hasn't been developed by upstream for 4 years and only runs with ruby 1.8. For an actively-developer alternative look at tarsnap and others. ruby_1_8 has been removed as it's not supported from upstream anymore and probably contains security issues. tidy-html5 package is removed. Upstream only provided (lib)tidy5 during development, and now they went back to (lib)tidy to work as a drop-in replacement of the original package that has been unmaintained for years. You can (still) use the html-tidy package, which got updated to a stable release from this new upstream. extraDeviceOptions argument is removed from bumblebee package. Instead there are now two separate arguments: extraNvidiaDeviceOptions and extraNouveauDeviceOptions for setting extra X11 options for nvidia and nouveau drivers, respectively. The Ctrl+Alt+Backspace key combination no longer kills the X server by default. There's a new option services.xserver.enableCtrlAltBackspace allowing to enable the combination again. emacsPackagesNg now contains all packages from the ELPA, MELPA, and MELPA Stable repositories. Data directory for Postfix MTA server is moved from /var/postfix to /var/lib/postfix. Old configurations are migrated automatically. service.postfix module has also received many improvements, such as correct directories' access rights, new aliasFiles and mapFiles options and more. Filesystem options should now be configured as a list of strings, not a comma-separated string. The old style will continue to work, but print a warning, until the 16.09 release. An example of the new style: fileSystems."/example" = { device = "/dev/sdc"; fsType = "btrfs"; options = [ "noatime" "compress=lzo" "space_cache" "autodefrag" ]; }; CUPS, installed by services.printing module, now has its data directory in /var/lib/cups. Old configurations from /etc/cups are moved there automatically, but there might be problems. Also configuration options services.printing.cupsdConf and services.printing.cupsdFilesConf were removed because they had been allowing one to override configuration variables required for CUPS to work at all on NixOS. For most use cases, services.printing.extraConf and new option services.printing.extraFilesConf should be enough; if you encounter a situation when they are not, please file a bug. There are also Gutenprint improvements; in particular, a new option services.printing.gutenprint is added to enable automatic updating of Gutenprint PPMs; it's greatly recommended to enable it instead of adding gutenprint to the drivers list. services.xserver.vaapiDrivers has been removed. Use services.hardware.opengl.extraPackages{,32} instead. You can also specify VDPAU drivers there. programs.ibus moved to i18n.inputMethod.ibus. The option programs.ibus.plugins changed to i18n.inputMethod.ibus.engines and the option to enable ibus changed from programs.ibus.enable to i18n.inputMethod.enabled. i18n.inputMethod.enabled should be set to the used input method name, "ibus" for ibus. An example of the new style: i18n.inputMethod.enabled = "ibus"; i18n.inputMethod.ibus.engines = with pkgs.ibus-engines; [ anthy mozc ]; That is equivalent to the old version: programs.ibus.enable = true; programs.ibus.plugins = with pkgs; [ ibus-anthy mozc ]; services.udev.extraRules option now writes rules to 99-local.rules instead of 10-local.rules. This makes all the user rules apply after others, so their results wouldn't be overriden by anything else. Large parts of the services.gitlab module has been been rewritten. There are new configuration options available. The stateDir option was renamned to statePath and the satellitesDir option was removed. Please review the currently available options. The option services.nsd.zones.<name>.data no longer interpret the dollar sign ($) as a shell variable, as such it should not be escaped anymore. Thus the following zone data: \$ORIGIN example.com. \$TTL 1800 @ IN SOA ns1.vpn.nbp.name. admin.example.com. ( Should modified to look like the actual file expected by nsd: $ORIGIN example.com. $TTL 1800 @ IN SOA ns1.vpn.nbp.name. admin.example.com. ( service.syncthing.dataDir options now has to point to exact folder where syncthing is writing to. Example configuration should loook something like: services.syncthing = { enable = true; dataDir = "/home/somebody/.syncthing"; user = "somebody"; }; Other notable improvements: The command-not-found hook was extended. Apart from $NIX_AUTO_INSTALL variable, it newly also checks for $NIX_AUTO_RUN which causes it to directly run the missing commands via nix-shell (without installing anything). ejabberd module is brought back and now works on NixOS. Input method support was improved. New NixOS modules (fcitx, nabi and uim), fcitx engines (chewing, hangul, m17n, mozc and table-other) and ibus engines (hangul and m17n) have been added.