- New options for the declarative configuration of the user space part of ALSA have been introduced under [hardware.alsa](#opt-hardware.alsa.enable), including setting the default capture and playback device, defining sound card aliases and volume controls.
  Note: these are intended for users not running a sound server like PulseAudio or PipeWire, but having ALSA as their only sound system.

- `services.k3s` now provides the `autoDeployCharts` option that allows to automatically deploy Helm charts via the k3s Helm controller.

- [Mattermost](#opt-services.mattermost.enable), a self-hosted chat collaboration platform supporting calls, playbooks, and boards, has been updated. It now has multiple versions, disabled telemetry, and a native frontend build in nixpkgs, removing all upstream prebuilt blobs.
  - Mattermost telemetry reporting is now disabled by default, though security update notifications are enabled. Look at [`services.mattermost.telemetry`](#opt-services.mattermost.telemetry.enableDiagnostics) for options to control this behavior.
  - The Mattermost module will produce eval warnings if a database password would end up in the Nix store, and recommend alternatives such as peer authentication or using the environment file.
  - We now support `mmctl` for Mattermost administration if both [](#opt-services.mattermost.socket.enable) and [](#opt-services.mattermost.socket.export) are set, which export the Mattermost control socket path into the system environment.

- `services.geoclue2` now uses [beaconDB](https://beacondb.net/) as a default geolocation service, replacing Mozilla Location Services which was [retired in June 2024](https://github.com/mozilla/ichnaea/issues/2065).

- `security.acme` now supports renewal using CSRs (Certificate Signing Request) through the options `security.acme.*.csr` and `security.acme.*.csrKey`.

- `programs.fzf.keybindings` now supports the fish shell.

- A toggle has been added under `users.users.<name>.enable` to allow toggling individual users conditionally. If set to false, the user account will not be created.

- New hooks were added:
  - `writableTmpDirAsHomeHook`: This setup hook ensures that the directory specified by the `HOME` environment variable is writable.
  - `addBinToPathHook`: This setup hook checks if the `bin/` directory exists in the `$out` output path and, if so, adds it to the `PATH` environment variable.
  - `gitSetupHook`: This setup hook sets up a valid Git configuration, including the `user.name` and `user.email` fields.

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## NixOS Wiki {#sec-release-25.05-wiki}

The official NixOS Wiki at [wiki.nixos.org](https://wiki.nixos.org) has new and improved articles, new contributors and some improvements in its dark theme and mobile readability.

```{=include=} sections
../release-notes-nixpkgs/rl-2505.section.md
```