- [btrbk](https://digint.ch/btrbk/index.html), a backup tool for btrfs subvolumes, taking advantage of btrfs specific capabilities to create atomic snapshots and transfer them incrementally to your backup locations. Available as [services.btrbk](options.html#opt-services.brtbk.instances).
- [geoipupdate](https://github.com/maxmind/geoipupdate), a GeoIP database updater from MaxMind. Available as [services.geoipupdate](options.html#opt-services.geoipupdate.enable).
- [sourcehut](https://sr.ht), a collection of tools useful for software development. Available as [services.sourcehut](options.html#opt-services.sourcehut.enable).
- [ucarp](https://download.pureftpd.org/pub/ucarp/README), an userspace implementation of the Common Address Redundancy Protocol (CARP). Available as [networking.ucarp](options.html#opt-networking.ucarp.enable).
- Users of flashrom should migrate to [programs.flashrom.enable](options.html#opt-programs.flashrom.enable) and add themselves to the `flashrom` group to be able to access programmers supported by flashrom.
- [buildkite-agent-metrics](https://github.com/buildkite/buildkite-agent-metrics), a command-line tool for collecting Buildkite agent metrics, now has a Prometheus exporter available as [services.prometheus.exporters.buildkite-agent](#opt-services.prometheus.exporters.buildkite-agent.enable).
- [influxdb-exporter](https://github.com/prometheus/influxdb_exporter) a Prometheus exporter that exports metrics received on an InfluxDB compatible endpoint is now available as [services.prometheus.exporters.influxdb](#opt-services.prometheus.exporters.influxdb.enable).
- [mx-puppet-discord](https://github.com/matrix-discord/mx-puppet-discord), a discord puppeting bridge for matrix. Available as [services.mx-puppet-discord](#opt-services.mx-puppet-discord.enable).
- [MeshCentral](https://www.meshcommander.com/meshcentral2/overview), a remote administration service ("TeamViewer but self-hosted and with more features") is now available with a package and a module: [services.meshcentral.enable](#opt-services.meshcentral.enable)
- [influxdb2](https://github.com/influxdata/influxdb), a Scalable datastore for metrics, events, and real-time analytics. Available as [services.influxdb2](#opt-services.influxdb2.enable).
- [fluidd](https://docs.fluidd.xyz/), a Klipper web interface for managing 3d printers using moonraker. Available as [fluidd](#opt-services.fluidd.enable).
- [sx](https://github.com/earnestly/sx), a simple alternative to both xinit and startx for starting a Xorg server. Available as [services.xserver.displayManager.sx](#opt-services.xserver.displayManager.sx.enable)
- [postfixadmin](https://postfixadmin.sourceforge.io/), a web based virtual user administration interface for Postfix mail servers. Available as [postfixadmin](#opt-services.postfixadmin.enable).
-`services.paperless.ocrLanguages` has no replacement. Users should migrate to [`services.paperless-ng.extraConfig`](options.html#opt-services.paperless-ng.extraConfig) instead:
- The `erigon` ethereum node has moved it's database location in `2021-08-03`, users upgrading must manually move their chaindata (see [release notes](https://github.com/ledgerwatch/erigon/releases/tag/v2021.08.03)).
-`consul` was upgraded to a new major release with breaking changes, see [upstream changelog](https://github.com/hashicorp/consul/releases/tag/v1.10.0).
-`yggdrasil` was upgraded to a new major release with breaking changes, see [upstream changelog](https://github.com/yggdrasil-network/yggdrasil-go/releases/tag/v0.4.0).
-`icingaweb2` was upgraded to a new release which requires a manual database upgrade, see [upstream changelog](https://github.com/Icinga/icingaweb2/releases/tag/v2.9.0).
-`tt-rss` was upgraded to the commit on 2021-06-21, which has breaking changes. If you use `services.tt-rss.extraConfig` you should migrate to the `putenv`-style configuration. See [this Discourse post](https://community.tt-rss.org/t/rip-config-php-hello-classes-config-php/4337) in the tt-rss forums for more details.
-`services.uptimed` now uses `/var/lib/uptimed` as its stateDirectory instead of `/var/spool/uptimed`. Make sure to move all files to the new directory.
- Deprecated package aliases in `emacs.pkgs.*` have been removed. These aliases were remnants of the old Emacs package infrastructure. We now use exact upstream names wherever possible.
- The `openrazer` and `openrazer-daemon` packages as well as the `hardware.openrazer` module now require users to be members of the `openrazer` group instead of `plugdev`. With this change, users no longer need be granted the entire set of `plugdev` group permissions, which can include permissions other than those required by `openrazer`. This is desirable from a security point of view. The setting [`harware.openrazer.users`](options.html#opt-services.hardware.openrazer.users) can be used to add users to the `openrazer` group.
- The fontconfig service's dpi option has been removed.
Fontconfig should use Xft settings by default so there's no need to override one value in multiple places.
The user can set DPI via ~/.Xresources properly, or at the system level per monitor, or as a last resort at the system level with `services.xserver.dpi`.
- The `yambar` package has been split into `yambar` and `yambar-wayland`, corresponding to the xorg and wayland backend respectively. Please switch to `yambar-wayland` if you are on wayland.
- The `todoman` package was upgraded from 3.9.0 to 4.0.0. This introduces breaking changes in the [configuration file](https://todoman.readthedocs.io/en/stable/configure.html#configuration-file) format.
- The linux kernel package infrastructure was moved out of `all-packages.nix`, and restructured. Linux related functions and attributes now live under the `pkgs.linuxKernel` attribute set.
In particular the versioned `linuxPackages_*` package sets (such as `linuxPackages_5_4`) and kernels from `pkgs` were moved there and now live under `pkgs.linuxKernel.packages.*`. The unversioned ones (such as `linuxPackages_latest`) remain untouched.
- The setting [`services.openssh.logLevel`](options.html#opt-services.openssh.logLevel) `"VERBOSE"``"INFO"`. This brings NixOS in line with upstream and other Linux distributions, and reduces log spam on servers due to bruteforcing botnets.
However, if [`services.fail2ban.enable`](options.html#opt-services.fail2ban.enable) is `true`, the `fail2ban` will override the verbosity to `"VERBOSE"`, so that `fail2ban` can observe the failed login attempts from the SSH logs.
- Sway: The terminal emulator `rxvt-unicode` is no longer installed by default via `programs.sway.extraPackages`. The current default configuration uses `alacritty` (and soon `foot`) so this is only an issue when using a customized configuration and not installing `rxvt-unicode` explicitly.
-`python3` now defaults to Python 3.9. Python 3.9 introduces many deprecation warnings, please look at the [What's New In Python 3.9 post](https://docs.python.org/3/whatsnew/3.9.html) for more information.
-`qtile` hase been updated from '0.16.0' to '0.18.0', please check [qtile changelog](https://github.com/qtile/qtile/blob/master/CHANGELOG) for changes.
- The `claws-mail` package now references the new GTK+ 3 release branch, major version 4. To use the GTK+ 2 releases, one can install the `claws-mail-gtk2` package.
- The wordpress module provides a new interface which allows to use different webservers with the new option [`services.wordpress.webserver`](options.html#opt-services.wordpress.webserver). Currently `httpd` and `nginx` are supported. The definitions of wordpress sites should now be set in [`services.wordpress.sites`](options.html#opt-services.wordpress.sites).
- The [networking.wireless.iwd](options.html#opt-networking.wireless.iwd.enable) module has a new [networking.wireless.iwd.settings](options.html#opt-networking.wireless.iwd.settings) option.
- The [services.syncoid.enable](options.html#opt-services.syncoid.enable) module now properly drops ZFS permissions after usage. Before it delegated permissions to whole pools instead of datasets and didn't clean up after execution. You can manually look this up for your pools by running `zfs allow your-pool-name` and use `zfs unallow syncoid your-pool-name` to clean this up.
- Zfs: `latestCompatibleLinuxPackages` is now exported on the zfs package. One can use `boot.kernelPackages = config.boot.zfs.package.latestCompatibleLinuxPackages;` to always track the latest compatible kernel with a given version of zfs.
- Nginx will use the value of `sslTrustedCertificate` if provided for a virtual host, even if `enableACME` is set. This is useful for providers not using the same certificate to sign OCSP responses and server certificates.
- MariaDB was upgraded from 10.5.x to 10.6.x. Please read the [upstream release notes](https://mariadb.com/kb/en/changes-improvements-in-mariadb-106/) for changes and upgrade instructions.
- The MariaDB C client library, also known as libmysqlclient or mariadb-connector-c, was upgraded from 3.1.x to 3.2.x. While this should hopefully not have any impact, this upgrade comes with some changes to default behavior, so you might want to review the [upstream release notes](https://mariadb.com/kb/en/changes-and-improvements-in-mariadb-connector-c-32/).
- GNOME desktop environment now enables `QGnomePlatform` as the Qt platform theme, which should avoid crashes when opening file chooser dialogs in Qt apps by using XDG desktop portal. Additionally, it will make the apps fit better visually.
-`rofi` has been updated from '1.6.1' to '1.7.0', one important thing is the removal of the old xresources based configuration setup. Read more [in rofi's changelog](https://github.com/davatorium/rofi/blob/cb12e6fc058f4a0f4f/Changelog#L1).
- ipfs now defaults to not listening on you local network. This setting was change as server providers won't accept port scanning on their private network. If you have several ipfs instances running on a network you own, feel free to change the setting `ipfs.localDiscovery = true;`. localDiscovery enables different instances to discover each other and share data.