- The ibus-table input method has had a change in config format, which causes all previous settings to be lost. See [this commit message](https://github.com/mike-fabian/ibus-table/commit/f9195f877c5212fef0dfa446acb328c45ba5852b) for details.
- NixOS module system type `types.optionSet` and `lib.mkOption` argument `options` are deprecated. Use `types.submodule` instead. ([\#54637](https://github.com/NixOS/nixpkgs/pull/54637))
- `matrix-synapse` has been updated to version 0.99. It will [no longer generate a self-signed certificate on first launch](https://github.com/matrix-org/synapse/pull/4509) and will be [the last version to accept self-signed certificates](https://matrix.org/blog/2019/02/05/synapse-0-99-0/). As such, it is now recommended to use a proper certificate verified by a root CA (for example Let's Encrypt). The new [manual chapter on Matrix](#module-services-matrix) contains a working example of using nginx as a reverse proxy in front of `matrix-synapse`, using Let's Encrypt certificates.
- `mailutils` now works by default when `sendmail` is not in a setuid wrapper. As a consequence, the `sendmailPath` argument, having lost its main use, has been removed.
- `graylog` has been upgraded from version 2.\* to 3.\*. Some setups making use of extraConfig (especially those exposing Graylog via reverse proxies) need to be updated as upstream removed/replaced some settings. See [Upgrading Graylog](http://docs.graylog.org/en/3.0/pages/upgrade/graylog-3.0.html#simplified-http-interface-configuration) for details.
- The option `users.ldap.bind.password` was renamed to `users.ldap.bind.passwordFile`, and needs to be readable by the `nslcd` user. Same applies to the new `users.ldap.daemon.rootpwmodpwFile` option.
- `nodejs-6_x` is end-of-life. `nodejs-6_x`, `nodejs-slim-6_x` and `nodePackages_6_x` are removed.
## Other Notable Changes {#sec-release-19.03-notable-changes}
- The `services.matomo` module gained the option `services.matomo.package` which determines the used Matomo version.
The Matomo module now also comes with the systemd service `matomo-archive-processing.service` and a timer that automatically triggers archive processing every hour. This means that you can safely [ disable browser triggers for Matomo archiving ](https://matomo.org/docs/setup-auto-archiving/#disable-browser-triggers-for-matomo-archiving-and-limit-matomo-reports-to-updating-every-hour) at `Administration > System > General Settings`.
Additionally, you can enable to [ delete old visitor logs ](https://matomo.org/docs/privacy/#step-2-delete-old-visitors-logs) at `Administration > System > Privacy`, but make sure that you run `systemctl start matomo-archive-processing.service` at least once without errors if you have already collected data before, so that the reports get archived before the source data gets deleted.
- `composableDerivation` along with supporting library functions has been removed.
- The deprecated `truecrypt` package has been removed and `truecrypt` attribute is now an alias for `veracrypt`. VeraCrypt is backward-compatible with TrueCrypt volumes. Note that `cryptsetup` also supports loading TrueCrypt volumes.
- The Kubernetes DNS addons, kube-dns, has been replaced with CoreDNS. This change is made in accordance with Kubernetes making CoreDNS the official default starting from [Kubernetes v1.11](https://github.com/kubernetes/kubernetes/blob/master/CHANGELOG-1.11.md#sig-cluster-lifecycle). Please beware that upgrading DNS-addon on existing clusters might induce minor downtime while the DNS-addon terminates and re-initializes. Also note that the DNS-service now runs with 2 pod replicas by default. The desired number of replicas can be configured using: `services.kubernetes.addons.dns.replicas`.
- The quassel-webserver package and module was removed from nixpkgs due to the lack of maintainers.
- The manual gained a [ new chapter on self-hosting `matrix-synapse` and `riot-web` ](#module-services-matrix), the most prevalent server and client implementations for the [Matrix](https://matrix.org/) federated communication network.