+There are several optional dependencies; we will talk about that later.
+
+Compiling Quassel - short version
+---------------------------------
+
+Quassel uses CMake as its build system. The canonical way to build any CMake-
+based project is as follows:
+
+cd /path/to/source
+mkdir build
+cd build
+cmake ..
+make
+make install
+
+Compiling Quassel - long version
+--------------------------------
+
+First of all, it is highly recommended for any CMake-based project to be built
+in a separate build directory rather than in-source. That way, your source
+checkout remains pristine, and you can easily remove any build artifacts by just
+deleting the build directory. This directory can be located anywhere; in the
+short example above, we've just created a directory called "build" inside the
+source checkout.
+
+From inside the build directory, you can then run the "cmake" command, followed
+by the path to the source. Additionally, you can append various options. Note
+that CMake caches the options you provide on the command line, so if you rerun
+it later in the same build directory, you don't need to specify them again.
+
+Quassel supports several options to enable or disable features, and can make
+use of several optional dependencies if installed. CMake will give a nice
+summary of all that after its run, so we'll just mention the most important
+options here:
+
+-DWANT_(CORE|QTCLIENT|MONO)=(ON|OFF)
+ Choose which Quassel binaries to build.
+
+-DUSE_CCACHE=ON
+ Enable ccache if the ccache binary is available. This avoids the need for
+ hacks using PATH or the CXX variable to make ccache work.
+ Distributors may want to disable automatic detection if they have their
+ own caching mechanism set up.
+
+-DUSE_QT4=ON
+ Build against the deprecated Qt4 instead of the default Qt5. Note that you
+ should empty your build directory when switching between Qt versions,
+ otherwise weird things may happen.
+
+-DWITH_KDE=ON
+ Enable integration into KDE4 (with Qt4) or KDE Frameworks (with Qt5).
+
+-DWITH_BUNDLED_ICONS=ON
+ Quassel requires a number of icons that are part of the KDE/Plasma icon themes
+ Breeze and Oxygen, but are generally not supported by other themes. In order
+ to avoid missing icons, Quassel bundles the subset of icons it uses from the
+ afforementioned themes, and uses that as a fallback if the system theme does
+ not provide a required icon.
+ If it is ensured that Breeze and/or Oxygen are installed on your system (e.g.
+ through package dependencies), this option can be turned off to save less
+ than 2 MB of disk space.
+
+-DWITH_OXYGEN_ICONS=(ON|OFF)
+ Support the Oxygen icon theme. Oxygen was the default theme in KDE 4, and
+ also the bundled icon theme in Quassel before version 0.13. Since the move
+ to Qt5, the more modern Breeze icon theme is preferred, and thus Oxygen
+ is disabled by default when building against Qt5.
+
+-DWITH_WEBENGINE=ON
+ Use WebEngine for showing previews of webpages linked in the chat. Requires
+ the QtWebEngine module to be available, and increases the client's RAM usage
+ by *a lot* if enabled at runtime. Only available for Qt5. The default is ON.
+
+-DWITH_WEBKIT=OFF
+ Use WebKit for showing previews of webpages linked in the chat. Requires
+ the QtWebKit module to be available, and increases the client's RAM usage
+ by *a lot* if enabled at runtime.
+ Note that WebKit support is deprecated and mostly unmaintained in Qt, and
+ should no longer be used for security reasons. The default is OFF.
+
+-DEMBED_DATA=(ON|OFF)
+ Specifies whether Quassel's data files (icons, translations and so on)
+ should be installed normally, or embedded into the binaries. The latter is
+ useful if you want to run Quassel from the build directory, or don't want
+ to use a standard installation. In particular, EMBED_DATA defaults to ON
+ on Windows and OS X, and to OFF on Linux.
+
+You can find the list of optional packages for additional features in CMake's
+feature summary; install missing packages for enabling the functionality listed
+in the explanation. If you want to forcefully disable an optional feature, use
+-DCMAKE_DISABLE_FIND_PACKAGE_Foo=TRUE, where "Foo" is the package name listed.
+
+Quassel also supports the usual CMake options, most importantly
+
+-DCMAKE_INSTALL_PREFIX=/prefix/path - specify the installation prefix
+-DCMAKE_BUILD_TYPE=(Debug|Release|RelWithDebug) - specify the build type
+
+If you want to narrow down the languages to be installed, you can set the
+LINGUAS environment variable with a space-separated list of language codes,
+for example LINGUAS="de en_US".
+
+After running CMake, you can just run "make" in the build directory, and
+"make install" for installing the result into the installation prefix.