Guidelines and HOWTOs/Build from source: Difference between revisions

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= Build KDE Frameworks and Applications =
= Build KDE Frameworks and Applications =
== Design features ==
Qt and most KDE software are written in C++ whereas its "competitor" GTK is written in C making it very portable and easy to produce language bindings for (for Ruby, Python, Bash etc.). So it is possible to write a complete GTK GUI app in Bash script, but so far that has not been done for Qt.


== Safety Precautions ==
== Safety Precautions ==
Configuring your build environment is the single most important step in building KDE.  Luckily, KDE frameworks development libraries are packaged by most major distributions.  In general, building and installing user space programs such as Calligra can be done safely without altering any system files. Whenever possible, it is recommended that you build KDE using your normal user account.  Unless you are interested in changing the behavior of your system, you should build with a normal account.  Even if you are a a KWin or Plasma developer wishing to test a full KDE session with compositing effects, there are ways to construct the desired testing bed entirely within your normal user account, e.g. running Plasma through a nested X server using xypher.
Configuring your build environment is the single most important step in building KDE software.  Luckily, KDE Frameworks development libraries are packaged by most major distributions.  In general, building and installing user space programs such as Calligra can be done safely without altering any system files. Whenever possible, it is recommended that you build KDE using your normal user account.  Unless you are interested in changing the behavior of your system, you should build with a normal account.  Even if you are a a KWin or Plasma developer wishing to test a full Plasma session with compositing effects, there are ways to construct the desired testing bed entirely within your normal user account, e.g. running Plasma through a nested X server using xypher.


However, to permanently alter your KDE/Plasma desktop environment through new System Configuration Modules and the like, you will often need to install shared libraries and other files in system folders. In these cases, bad installation can render your system unstable or your desktop environment unusable.  '''Always take caution before executing any commands as root!'''  A <code>sudo make install</code> '''can not always be undone by''' a simple <code>sudo make uninstall.</code> Technologies like containerization may help solve these problems in the future, but current distribution systems have no way to monitor the alterations you make to system shared libraries as the system administrator. Always keep records of what you are doing and make sure you know how to access the install logs to give yourself a better chance of reverting files by hand if necessary. And of course, please keep high quality, frequent backups of your data.
However, to permanently alter your Plasma desktop environment through new System Configuration Modules and the like, you will often need to install shared libraries and other files in system folders. In these cases, bad installation can render your system unstable or your desktop environment unusable.  '''Always take caution before executing any commands as root!'''  A <code>sudo make install</code> '''can not always be undone by''' a simple <code>sudo make uninstall</code>   .  Technologies like containerization may help solve these problems in the future, but current distribution systems have no way to monitor the alterations you make to system shared libraries as the system administrator. Another option is to use snapshots of a BTRfs formatted system harddisk and use snapper-GUI to roll back in case of an error. Always keep records of what you are doing and make sure you know how to access the install logs to give yourself a better chance of reverting files by hand if necessary. And of course, please keep high quality, frequent backups of your data.


== Configuration scripts  ==
== Configuration scripts  ==
A set of configuration scripts and bash commands are provided as a recommended configuration when building KDE manually.  If you use these as provided then your KDE build will be a lot easier and it will be easier for you to find support online. The one disadvantage to these scripts is that they hide important details from you which you may want to learn about. However the scripted and by-hand methods are completely interchangeable so once you are comfortable building KDE using the scripts you can learn more by doing everything yourself.
A set of configuration scripts and bash commands are provided as a recommended configuration when building KDE software manually.  If you use these as provided then your build will be a lot easier and it will be easier for you to find support online. The one disadvantage to these scripts is that they hide important details from you which you may want to learn about. However the scripted and by-hand methods are completely interchangeable so once you are comfortable building KDE using the scripts you can learn more by doing everything yourself.


If you want to do the work by hand you can follow the [[/Details|detailed instructions]] else continue here on.
If you want to do the work by hand you can follow the [[/Details|detailed instructions]] else continue here on.
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This section provides information about '''required''' and '''optional''' software packages needed to build the KDE applications.
This section provides information about '''required''' and '''optional''' software packages needed to build the KDE applications.


[https://www.qt.io/ Qt5] is the base of KDE software. Your distro provides suitable devel packages. Optionally, you can [[/OwnQt5| build your own Qt5]].
[https://www.qt.io/ Qt5] is the base of KDE software. Your distro provides suitable devel packages containing prominently the Qt C++ header files below /usr/include/****'''.h''' . Optionally, you can [[/OwnQt5| build your own Qt5]].


Follow this page to [[/Install the dependencies|install the required dependencies]].
Follow this page to [[/Install the dependencies|install the required dependencies]].


== Git remote prefix ==
== Git remote prefix ==
Let's setup a "kde:" prefix for git commands. Add the following text to your ~/.gitconfig:
See [[Get Involved/development#Configure Git]]
<syntaxhighlight lang="ini">
[url "git://anongit.kde.org/"]
  insteadOf = kde:
[url "ssh://[email protected]/"]
  pushInsteadOf = kde:
</syntaxhighlight>
 
If you are behind a firewall, add the following text to your ~/.gitconfig :
<syntaxhighlight lang="ini">
[url "https://anongit.kde.org/"]
  insteadOf = kde:
[url "ssh://[email protected]/"]
  pushInsteadOf = kde:
</syntaxhighlight>


== kdesrc-build ==
== kdesrc-build ==
''kdesrc-build'' is a user-space package manager. It is used to compile KDE-related projects from source, and to install them into a designated directory. (see current master [https://cgit.kde.org/kdesrc-build.git/tree/README here])
See [[Get Involved/development#Set up kdesrc-build]]
 
This guide assumes that
* you want to install KDevelop inside your home directory,
* you want to put sources, build and log files into separate subdirectories under <tt>~/kde</tt>, as well as install everything to <tt>~/kde/usr</tt>, and
* you use a Linux system and are familiar with bash.
 
Make sure to adapt these steps to your needs.
 
=== Install kdesrc-build ===
 
Start off by installing ''kdesrc-build'' and creating a basic configuration file:
<pre>
mkdir -p ~/kde/src
cd ~/kde/src
git clone kde:kdesrc-build
cd kdesrc-build
 
# Install a symlink of kdesrc-build to a location in PATH
mkdir ~/bin
ln -s "$PWD/kdesrc-build" ~/bin
export PATH=~/bin:$PATH
</pre>
 
You will need to append the line <code>export PATH=~/bin:$PATH</code> to your <tt>~/.bashrc</tt> so <code>kdesrc-build</code> is available in PATH whenever you open a terminal. Also check that PATH variable is not set to anything by default in <tt>.bashrc</tt> file
 
=== Configure kdesrc-build ===
 
The easiest way to prepare your system is to use the wizard to create the ~/.kdesrc-buildrc you will need, the default options should be ok
<pre>
./kdesrc-build-setup
</pre>
Note: do not quote or escape any file paths.
 
2017-04-23: User question:
* When I take a look at ~/.kdesrc-buildrc I see this line `source-dir ~/kdesrc` ("Directory for downloaded source code") and I wonder if this is correct because above we said that the source directory is '''~/kde/src'''.
 
=== Run kdesrc-build ===
 
To let <code>kdesrc-build</code> handle the compilation and installation of KDevelop and its (direct) dependencies, type
 
<syntaxhighlight lang="bash">
$ kdesrc-build --debug libkomparediff2 kdevplatform kdevelop-pg-qt kdevelop
</syntaxhighlight>
 
The <tt>--debug</tt> parameter will give you the verbose output, all command invocations and compiler output. Helpful for trouble-shooting. If you want to compile and install indirect dependencies as well, make sure to add the <tt>--include-dependencies</tt> parameter as well.
 
=== Set up a script for preparing the environment ===
 
Copy and use these commands to a new file called ~/kde/.setup-env:
<syntaxhighlight lang="ini">
export KF5=~/kde/usr
export QTDIR=/usr 
export CMAKE_PREFIX_PATH=$KF5:$CMAKE_PREFIX_PATH 
export XDG_DATA_DIRS=$KF5/share:$XDG_DATA_DIRS:/usr/share 
export XDG_CONFIG_DIRS=$KF5/etc/xdg:$XDG_CONFIG_DIRS:/etc/xdg 
export PATH=$KF5/bin:$QTDIR/bin:$PATH 
export QT_PLUGIN_PATH=$KF5/lib/plugins:$KF5/lib64/plugins:$KF5/lib/x86_64-linux-gnu/plugins:$QTDIR/plugins:$QT_PLUGIN_PATH 
# (lib64 instead of lib on some systems, like OpenSUSE)
export QML2_IMPORT_PATH=$KF5/lib/qml:$KF5/lib64/qml:$KF5/lib/x86_64-linux-gnu/qml:$QTDIR/qml 
export QML_IMPORT_PATH=$QML2_IMPORT_PATH 
export KDE_SESSION_VERSION=5 
export KDE_FULL_SESSION=true
export SASL_PATH=/usr/lib/sasl2:$KF5/lib/sasl2
# (lib64 instead of lib on some systems, like OpenSUSE)
PS1="(kdesrc) $PS1"
</syntaxhighlight>
 
A guide for building Plasma 5 specifically on Ubuntu 14.04 LTS can be found [[/Plasma_5_on_Ubuntu_14.04_LTS|here]].
 
=== Run KDevelop ===
 
Whenever you want to run a self-compiled KDevelop, you just have to do the following commands in terminal:
<syntaxhighlight lang="bash">
$ source ~/kde/.setup-env
$ kdevelop
</syntaxhighlight>
 
=== Analyse and fix build errors ===
 
First and foremost check that you have installed the dependencies mentioned in the wiki at [https://community.kde.org/Guidelines_and_HOWTOs/Build_from_source/Install_the_dependencies here]
 
If ''kdesrc-build'' shows you red module names with messages like "Unable to configure plasma-mediacenter with CMake!" or "Unable to build kdepim!", you have to start troubleshooting.
 
<pre>
<<<  PACKAGES FAILED TO BUILD  >>>
libkomparediff2 - ~/kde/log/<build-date>/libkomparediff2/error.log  :-(
</pre>
 
Inspect that log to figure out what's going on:
 
==== Missing ecm-config.cmake ====
<syntaxhighlight lang="bash">
$ cat ~/kde/log/<build-date>/libkomparediff2/error.log
</syntaxhighlight>
<pre>
CMake Error at CMakeLists.txt:5 (find_package):
  Could not find a package configuration file provided by "ECM" (requested
  version 0.0.9) with any of the following names:
  ECMConfig.cmake
  ecm-config.cmake
  Add the installation prefix of "ECM" to CMAKE_PREFIX_PATH or set "ECM_DIR"
  to a directory containing one of the above files.  If "ECM" provides a
  separate development package or SDK, be sure it has been installed.
</pre>
 
In this case, the ECM (extra cmake modules) package is missing. Since ECM is a KDE Framework, this error would have been avoided by the <tt>--include-dependencies</tt> parameter mentioned above.
 
However, this might also happen with dependencies that ''kdesrc-build'' is not able to handle itself. In such cases, you have to install additional packages via your system package manager. Most distribution offer ways to determine which package contains the missing files.
 
For Ubuntu, you would head over to http://packages.ubuntu.com and search for the distro package providing a particular file (ECMConfig.cmake in this case). The package search reveals <tt>extra-cmake-modules</tt> being a hot candidate; to fix above error we simply install the package and the restart the build:
 
<syntaxhighlight lang="bash">
$ sudo apt-get install extra-cmake-modules
$ kdesrc-build ...
</syntaxhighlight>
 
The error should be gone now.
==== Missing Qt5Config.cmake====
 
<pre>
CMake Error at CMakeLists.txt:45 (find_package):
  Could not find a package configuration file provided by "Qt5" (requested
  version 5.2.0) with any of the following names:
 
    Qt5Config.cmake
    qt5-config.cmake
</pre>
 
It can be fixed by installing the dependeny
<pre>sudo apt-get install qtbase5-dev</pre>
 
Run again the kdesrc-build command, and it should be fine
 
==== Missing Qt5WebKitWidgetsConfig.cmake====
 
<pre>
CMake Error at /usr/lib/x86_64-linux-gnu/cmake/Qt5/Qt5Config.cmake:26 (find_package):
  Could not find a package configuration file provided by "Qt5WebKitWidgets"
  with any of the following names:
 
    Qt5WebKitWidgetsConfig.cmake
    qt5webkitwidgets-config.cmake
</pre>
 
It can be fixed by installing the dependeny
<pre>sudo apt-get install libqt5webkit5-dev</pre>
 
Run again the kdesrc-build command, and it should be fine


= Testing =
= Testing =
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<syntaxhighlight lang="bash">
<syntaxhighlight lang="bash">
xvfb-run -s '-screen 0 1024x768x24' /path/to/awesome-run make test
$ xvfb-run -s '-screen 0 1024x768x24' /path/to/awesome-run make test
</syntaxhighlight>
</syntaxhighlight>


Line 230: Line 71:


<syntaxhighlight lang="bash">
<syntaxhighlight lang="bash">
make Experimental
$ make Experimental
</syntaxhighlight>
</syntaxhighlight>


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== Testing Plasma ==
== Testing Plasma ==


The following page details how to [[/Test plasma | test Plasma]].
See [[Get Involved/development#Plasma]]


= Troubleshooting =
= Troubleshooting =


== Compilation: how to quickly solve build problems ==
== Compilation: how to quickly solve build problems ==
 
See [[Get Involved/development#How to solve build problems]]
'''Situation:'''
 
One or more modules fail to build via <code>kdesrc-build</code> (displayed in red font).
 
'''Steps to solve''' (in the given order):
 
The following steps assume the directory structure as proposed in the ''kdesrc-build'' guide above.
# You may not have all dependencies installed. Read the output to see what missing dependency it is complaining about, search for the corresponding package for your distro, and install it.
# Check the [https://build.kde.org/view/FAILED/ list of currently broken modules] on the KDE build server.
# If you get a build failure, simple fix might be to delete the build folder for that module and try building it again.
# See [[#Analyse_and_fix_build_errors | Analyse and fix build errors]].
# Delete <tt>~/kde/build</tt> and <tt>~/kde/usr</tt>. Run <code>kdesrc-build</code> again.
# Ask for help on IRC or some mailing list, see [[Getinvolved/development#Communicating_with_the_team| Communicating with the team]].
# Check if there are changes in the build instructions: see [https://community.kde.org/index.php?title=Guidelines_and_HOWTOs/Build_from_source&action=history History of this wiki page].
# Start over from scratch.


== Runtime: Segfault when a sound is about to play (e.g. for a message box) ==
== Runtime: Segfault when a sound is about to play (e.g. for a message box) ==
Line 293: Line 118:


# Locate bluedevil files using <code>locate bluedevil</code>, for example.  
# Locate bluedevil files using <code>locate bluedevil</code>, for example.  
# Among the files there is <tt>kde/usr/share/kservices5/kded/bluedevil.desktop</code>. Remove it. If it was the cause, kded should stop crashing
# Among the files there is <code>kde/usr/share/kservices5/kded/bluedevil.desktop</code>. Remove it. If it was the cause, kded should stop crashing


'''Goal 2: Remove bluedevil from kdesrcbuild until it gets fixed.'''
'''Goal 2: Remove bluedevil from kdesrcbuild until it gets fixed.'''
Line 309: Line 134:


Further calls of <code>kdesrc-build</code> will not include the component.
Further calls of <code>kdesrc-build</code> will not include the component.
== Runtime: Couldn't start kded5 (KDE4) ==
(added: 2014-Dec)
'''Situation:''' Developing and executing KF5 apps under KDE 4.
Problem by example: Error message on console when starting ksnapshot in KF5 environment
<pre  style="white-space: pre-wrap; white-space: -moz-pre-wrap; white-space: -pre-wrap; white-space: -o-pre-wrap; word-wrap: normal;">
ksnapshot(26577)/default KSycocaPrivate::checkDatabase: Couldn't start kded5 from org.kde.kded5.service: QDBusError("org.freedesktop.DBus.Error.ServiceUnknown", "The name org.kde.kded5 was not provided by any .service files") , falling back to running kbuildsycoca5
</pre>
'''Solution (not verified yet):''' As said in the article, run this command before starting the app itself:
<syntaxhighlight lang="bash">
$ . ~/kde/.setup/env      # (or as your script is called)
$ eval `dbus-launch`    # no output expected
$ ksnapshot            # no kded5 error message expected
</syntaxhighlight>
== Runtime: Icon theme was changed (KDE4) ==
(added: 2014-Oct, verified: 2015-Feb)
'''Situation:''' developing and executing KF5 apps under KDE 4.
Problem: After working a bit with KF5 applications, your regular KDE icon theme might be changed from oxygen to breeze.
Solution: see https://forum.kde.org/viewtopic.php?f=67&t=25032: Open "Icons - KDE Control Module" and change the theme back to Oxygen.


== Get more help ==
== Get more help ==
Line 342: Line 139:
If you still have trouble with the building process or runtime setup, you can contact people as described in [[Get_Involved/development#Communicating_with_the_team|Communicating with the team]].
If you still have trouble with the building process or runtime setup, you can contact people as described in [[Get_Involved/development#Communicating_with_the_team|Communicating with the team]].


Feel free to join us by visiting [irc://irc.freenode.net/#kde-devel #kde-devel on Freenode]. A web-based client can be found at https://kiwiirc.com/client/irc.freenode.org/kde-devel
Feel free to join us by visiting [irc://irc.freenode.net/#kde-devel #kde-devel on Freenode]. A webcaptcha-based client can be found at https://kiwiirc.com/client/irc.freenode.org/kde-devel


= Alternative building methods =
= Alternative building methods =
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== Kubuntu CI ==
== Kubuntu CI ==
[[Kubuntu/PPAs#Kubuntu_Continuous_Integration_.28CI.29|Kubuntu CI]] (replaces Project Neon 5) provides packages of KDE Git master for KDE Frameworks and Plasma 5.  Install them on your Kubuntu system to work with KDE Git.
[[Kubuntu/PPAs#Kubuntu_Continuous_Integration_.28CI.29|Kubuntu CI]] (replaces Project Neon 5) provides packages of KDE Git master for KDE Frameworks and Plasma 5.  Install them on your Kubuntu system to work with KDE Git.
== openSUSE Build Service ==
[https://en.opensuse.org/SDB:KDE_repositories#Unstable_Frameworks.2C_Plasma_and_Applications The openSUSE Build Service] provides packages of KDE Git master for KDE Frameworks, Plasma, Applications and Extragear. It offers repositories for Tumbleweed and the latest stable (Leap) release.


== Docker ==
== Docker ==
The docker container keeps the target KDE separate from the working installation, so no "contamination" with unstable code can occur.
* [[/Alternatives | Build with docker]]
* [[/Alternatives | Build with docker]]

Revision as of 16:19, 3 May 2020

Build KDE Frameworks and Applications

Design features

Qt and most KDE software are written in C++ whereas its "competitor" GTK is written in C making it very portable and easy to produce language bindings for (for Ruby, Python, Bash etc.). So it is possible to write a complete GTK GUI app in Bash script, but so far that has not been done for Qt.

Safety Precautions

Configuring your build environment is the single most important step in building KDE software. Luckily, KDE Frameworks development libraries are packaged by most major distributions. In general, building and installing user space programs such as Calligra can be done safely without altering any system files. Whenever possible, it is recommended that you build KDE using your normal user account. Unless you are interested in changing the behavior of your system, you should build with a normal account. Even if you are a a KWin or Plasma developer wishing to test a full Plasma session with compositing effects, there are ways to construct the desired testing bed entirely within your normal user account, e.g. running Plasma through a nested X server using xypher.

However, to permanently alter your Plasma desktop environment through new System Configuration Modules and the like, you will often need to install shared libraries and other files in system folders. In these cases, bad installation can render your system unstable or your desktop environment unusable. Always take caution before executing any commands as root! A sudo make install can not always be undone by a simple sudo make uninstall . Technologies like containerization may help solve these problems in the future, but current distribution systems have no way to monitor the alterations you make to system shared libraries as the system administrator. Another option is to use snapshots of a BTRfs formatted system harddisk and use snapper-GUI to roll back in case of an error. Always keep records of what you are doing and make sure you know how to access the install logs to give yourself a better chance of reverting files by hand if necessary. And of course, please keep high quality, frequent backups of your data.

Configuration scripts

A set of configuration scripts and bash commands are provided as a recommended configuration when building KDE software manually. If you use these as provided then your build will be a lot easier and it will be easier for you to find support online. The one disadvantage to these scripts is that they hide important details from you which you may want to learn about. However the scripted and by-hand methods are completely interchangeable so once you are comfortable building KDE using the scripts you can learn more by doing everything yourself.

If you want to do the work by hand you can follow the detailed instructions else continue here on.

Install required devel packages

This section provides information about required and optional software packages needed to build the KDE applications.

Qt5 is the base of KDE software. Your distro provides suitable devel packages containing prominently the Qt C++ header files below /usr/include/****.h . Optionally, you can build your own Qt5.

Follow this page to install the required dependencies.

Git remote prefix

See Get Involved/development#Configure Git

kdesrc-build

See Get Involved/development#Set up kdesrc-build

Testing

Running unit tests

Unit tests are ran from the build dir of each framework; you should first cd into it.

You need a separate DBus session because the dbus server needs to have the right value of XDG_DATA_DIRS, in order to find $KF5/share/dbus-1/services for starting services (e.g. kded5).

 $ eval `dbus-launch`
 $ kdeinit5
 $ make test

Note: Regular apps will start kdeinit5 automatically. The reason it has to be started by hand when running unit tests is some strange interaction with ctest.

Warning: never start a KDE 4 application in this separate DBus session. It would conflict with your running Plasma 4 desktop.

Note: KDE_FULL_SESSION=true is needed to make sure that the correct QPA will be loaded.

Many of the tests require an X server, and will pop up windows briefly. An easy way to allow these tests to run without interfering with your normal X session is to do

 $ xvfb-run -s '-screen 0 1024x768x24' make test

The -s argument tells Xvfb to set the first screen to be 1024x768 pixels, with a depth of 24; at least one test requires a depth greater than 8. In this case, if you also ensure DBUS_SESSION_BUS_ADDRESS is not set, the tests should not find your existing DBus session, and instead launch a new DBus instance.

Note that the KWindowSystem tests require a NETWM-compatible window manager to be running. One way to do this is to create a script to run such a window manager, followed by whatever is passed to it. For example, if you have the window manager awesome installed, you could create a script called awesome-run as follows:

#!/bin/sh
awesome &
exec "$@"

and then run the tests as

$ xvfb-run -s '-screen 0 1024x768x24' /path/to/awesome-run make test

If you want to publish your test results, instead of "make test" run

$ make Experimental

The test results will appear on http://my.cdash.org/index.php?project=<projectname>

Testing Plasma

See Get Involved/development#Plasma

Troubleshooting

Compilation: how to quickly solve build problems

See Get Involved/development#How to solve build problems

Runtime: Segfault when a sound is about to play (e.g. for a message box)

(added: 2015-02-27)

Example of the problem: open kate, edit some file without saving, Ctrl+W to close, a message box is about to appear and the then segfault:

 kate(9037)/default KNotificationManager::notify: Calling notify on "Sound"
 Segmentation fault

This command can solve the problem:

 $ sudo /usr/lib64/vlc/vlc-cache-gen -f /usr/lib64/vlc/plugins

See also:

Alternative: go to kf5/build/kdesupport/phonon/phonon-vlc/ and exec `make uninstall`

Runtime: kded5 crashes because of some component

(added: 2015-Jan)

Situation: kded5 is started but crashes because of some dependency. Stacktraces show for example `bluedevil` as possible cause.

Goal 1: Disable the component to verify it as crash cause.

Steps:

  1. Locate bluedevil files using locate bluedevil, for example.
  2. Among the files there is kde/usr/share/kservices5/kded/bluedevil.desktop. Remove it. If it was the cause, kded should stop crashing

Goal 2: Remove bluedevil from kdesrcbuild until it gets fixed.

Steps:

  1. Search through the dev/kf5/src/extragear/utils/kdesrc-build/*-build-include files to find the component. In this case, it was found in kf5-workspace-build-include.
  2. Comment it out:
 # module-set kf5-bluetooth-management
 #     repository kde-projects
 #     use-modules libbluedevil bluedevil
 # end module-set

Further calls of kdesrc-build will not include the component.

Get more help

If you still have trouble with the building process or runtime setup, you can contact people as described in Communicating with the team.

Feel free to join us by visiting #kde-devel on Freenode. A webcaptcha-based client can be found at https://kiwiirc.com/client/irc.freenode.org/kde-devel

Alternative building methods

Kubuntu CI

Kubuntu CI (replaces Project Neon 5) provides packages of KDE Git master for KDE Frameworks and Plasma 5. Install them on your Kubuntu system to work with KDE Git.

openSUSE Build Service

The openSUSE Build Service provides packages of KDE Git master for KDE Frameworks, Plasma, Applications and Extragear. It offers repositories for Tumbleweed and the latest stable (Leap) release.

Docker

The docker container keeps the target KDE separate from the working installation, so no "contamination" with unstable code can occur.