Get Involved/development/Set up a development environment

Information

Everything on this page only needs to be done once. Once you've done it, your development environment is set up and you can use it to submit patches and develop KDE Software!

Note

This procedure will set up kdesrc-build for Qt5 and KDE Frameworks 5.
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, video tutorials can be found here.

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 install git cmake
• Arch/Manjaro: sudo pacman -S git cmake dialog extra-cmake-modules
• Fedora: sudo dnf install git cmake perl perl-IPC-Cmd perl-MD5 perl-FindBin
• openSUSE Leap & Tumbleweed: sudo zypper install git breezy cmake dialog

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

Note

If you use the zsh shell and you have selected yes for auto-completions during the initial setup for kdesrc-build, add the following two lines to the configuration file ~/.zshrc if the lines do not exist in the file.

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

This process installs 3rd-party dependencies once, but they can change over time, and 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:

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 manage and build software from source code!