Get Involved/development/Set up a development environment
Information
Note
Setting up kdesrc-build for Qt6 and KDE Frameworks 6 and setting up kdesrc-build inside a Docker container are advanced topics.
Source code for KDE software lives on KDE Invent. But before you can work on it, you'll need to set up a development environment: a set of tools that allows you to access and edit the source code, compile it into a form that the computer can run, and deploy it to a safe location. We will now go through the process of setting one up. To accomplish these tasks, you will need to enter commands using a terminal program, such as KDE's Konsole.
If you're not familiar with the command line interface, you can find tutorials here. However, advanced command-line skills are not required, and you will learn what you need along the way!
If you're a visual learner, we also provide video tutorials about setting up kdesrc-build.
Install basic tools
First you will need to use your operating system's package manager to install some basic tools:
- KDE Neon/Kubuntu/Ubuntu/Debian:
sudo apt update && sudo apt install git - Arch/Manjaro:
sudo pacman -S git cmake dialog extra-cmake-modules - Fedora:
sudo dnf install git perl perl-IPC-Cmd perl-MD5 perl-FindBin - openSUSE Tumbleweed:
sudo zypper refresh && sudo zypper install git
Configure Git
We need to set your authorship information properly so that any changes you make can be properly attributed to you:
git config --global user.name "Your Name" git config --global user.email "[email protected]"
The name you provide should be your actual name, not your KDE Identity username or a pseudonym. And the email address must be the same as the email address used for your https://bugs.kde.org account. If they don't match, then the BUG: and FEATURE: keywords won't work (see this page for more information).
Next, in order to authenticate yourself when pushing code changes, you need to add an ssh key to your GitLab profile as described here.
Set up kdesrc-build
kdesrc-build is the official KDE meta-build-system tool. It is used to manage the building of many software repositories in an automated fashion. Its primary purpose is to manage dependencies. Every software has dependencies: other pieces of software that provide lower-level functionality they rely on. In order to compile any piece of software, its dependencies must be available. KDE software has two types of dependencies: dependencies on other pieces of KDE software, and dependencies on 3rd-party software. E.g. the KDE application KCalc depends on more than 20 other KDE git repositories as well as the Qt toolkit.
Because most Linux operating systems do not provide development packages of the KDE Frameworks 5 and of other KDE libraries that are up-to-date enough for us to build from the "master" branch of the KDE git repositories, we use kdesrc-build compile them ourselves. The goal is to avoid using KDE binaries, libraries and other files from the OS (i.e. the /usr directory).
Let's set it up now! First, create a new directory for all the KDE source code. You will need many gigabytes of free disk space. Budget 50 GB for KDE Frameworks + KDE Plasma, and 10-30 GB more for some apps as well. Then clone the kdesrc-build git repository in that directory:
mkdir -p ~/kde/src cd ~/kde/src/ git clone https://invent.kde.org/sdk/kdesrc-build.git && cd kdesrc-build
Next, some distros need source repos enabled before you can install the development packages you need. Do that now, if needed:
- KDE neon/Debian/Ubuntu/Kubuntu/etc:
sudo sed -i '/^# deb-src/s/^# //' /etc/apt/sources.list && sudo apt update - openSUSE Leap & Tumbleweed:
sudo zypper mr -e $(zypper repos | awk '/source/{print $5}')
With that done, it's time to run the initial setup program, which will make some changes to your ~/.bashrc (or ~/.zshrc for zsh users) and install necessary 3rd-party packages:
./kdesrc-build --initial-setup source ~/.bashrc
The step ./kdesrc-build --initial-setup above installs the Linux binary packages that are needed such that kdesrc-buid can build all of the KDE Frameworks 5 and KDE Frameworks 6.
Note
kdesrc-build, add the following two lines to ~/.zshrc if these two lines are not already there:
autoload -U +X compinit && compinit autoload -U +X bashcompinit && bashcompinit
For more details about 3rd-party dependencies, see Get_Involved/development/Install_the_dependencies
Note
kdesrc-build is currently not smart enough to track those changes and apply them later; see https://invent.kde.org/sdk/kdesrc-build/-/issues/9 for more details. So if in the future, you happen to find any external dependencies needed to build KDE software that were not installed with kdesrc-build --initial-setup, then once you finish this tutorial, please send a merge request to https://invent.kde.org/sdk/kdesrc-build/-/blob/master/modules/ksb/FirstRun.pm in order to include the needed packages to the list.
Set up Qt
Qt is the fundamental framework that is needed for pretty much all KDE development. A recent enough version of Qt is required to proceed.
You can look up the version of the Qt framework installed on your operating system by opening the application "Info Center" (KInfoCenter) > Basic Information > About this System > "Qt Version:"
If Qt 5.15 or later is installed, you're already done done with this step and can proceed to the next section! 🎉
...Otherwise it's time to compile a more recent version of Qt using kdesrc-build. See Building Qt using kdesrc-build to learn how. If you're just getting started with development, it may be a good time to switch distros to something better suited for building KDE software from source code either as the primary operating system or in a virtual machine. But if you are an advanced user, feel free to compile your own Qt.
Disable indexing for your development environment
You'll want to disable indexing for your development-related git repos and the files they will build and install. Add ~/kde to the exclusions list in System Settings > Workspace > Search > File Search, like so:
Install kdesrc-build for Qt6
The most important git branch of many KDE git repositories requires Qt6.
In order to contribute source code changes to these KDE git repositories you need an installation of kdesrc-build that uses Qt6 (kdesrc-build kf6-qt6).
It is recommended that you install Qt6 from your Linux OS. There are two more advanced ways of installing Qt6: download and install already built Qt6 packages using the Qt Online Installer from www.qt.io or build and install Qt6 using kdesrc-build kf6-qt6.
You can find instructions on how to configure kdesrc-build for kf6-qt6 here.
In order to only build the Qt6 version of some KDE git repositories, append at the end of the file kdesrc-buildrc the lines:
options plasma-integration
cmake-options -DBUILD_WITH_QT6=ON -DBUILD_QT5=OFF
end options
options breeze
cmake-options -DBUILD_WITH_QT6=ON -DBUILD_QT5=OFF
end options
Packages needed by kdesrc-build kf6-qt6
"kdesrc-build --initial-setup" should install from your Operating System (OS) at least the packages that are needed for "kdesrc-build frameworks" to succeed for both kdesrc-build kf5-qt5 and kdesrc-build kf6-qt6.
Please install from your Operating System the following binary packages:
- Debian/Ubuntu:
sudo apt install qt6-tools-dev qt6-declarative-dev libqt6core5compat6-dev qt6-wayland qt6-wayland-dev qt6-wayland-dev-tools qt6-base-private-dev libqt6svg6-dev libqt6opengl6-dev libqt6shadertools6-dev doxygen xsltproc xmlto texinfo libutfcpp-dev sudo apt build-dep appstream # I.e. apt install libyaml-dev libsystemd-dev libgirepository1.0-dev libstemmer-dev itstool gi-docgen
- openSUSE Tumbleweed:
For Plasma you will also need the following runtime dependency: sudo zypper in qt6-qt5compat-imports
- Arch Linux:
sudo pacman -S poppler-qt6 qca-qt6 qt6-5compat qt6-base qt6-charts qt6-declarative qt6-multimedia qt6-multimedia-ffmpeg qt6-positioning qt6-tools qt6-translations qt6-wayland qt6-webchannel qt6-webengine qt6-websockets qt6-webview qtkeychain-qt6 qcoro-qt6 qt6-svg qt6-shadertools qt6-sensors
- Fedora:
sudo dnf install expat-devel libcurl-devel libyaml-devel gtk-doc sudo dnf builddep appstream
Next Steps
Reboot your computer and log back in so the package changes, and the ~/.bashrc changes take effect on your user account. Once that's done, your development environment is set up and ready to build software. Time to learn how to use kdesrc-build tool to build software from source code!