Compiling On Linux

Compiling software is the process of turning human-readable source code into machine code a computer can execute. Compiling Mixxx is fairly straightforward on Linux. The steps below outline what to do. If you need help after reading this page, feel free to ask questions on our Zulip chat.

Install build dependencies

Mixxx relies on several external libraries for various features.

Debian / Ubuntu / Raspbian

First of all install cmake, the tool that we need to build the project, running:

sudo apt-get install cmake

If your distribution is Debian 9/10 based (such as Ubuntu 16.04/18.04), you can install them by running:

sudo apt-get install g++ git scons cmake ccache libportmidi-dev libopusfile-dev \
  libshout-dev libtag1-dev libprotobuf-dev protobuf-compiler \
  libusb-1.0-0-dev libfftw3-dev libmad0-dev portaudio19-dev \
  libchromaprint-dev librubberband-dev libsqlite3-dev \
  libid3tag0-dev libflac-dev libsndfile-dev libupower-glib-dev \
  libavcodec-dev libavformat-dev \
  libgl-dev liblilv-dev \
  libjack-dev libjack0 portaudio19-dev \
  libfaad-dev libmp4v2-dev \
  libmp3lame-dev libebur128-dev qt5keychain-dev libmodplug-dev 

Note: libfaad-dev libmp4v2-dev are required for M4A support. The installation order is important.

Beginning with Debian 10 (Ubuntu 20.04) support for libmp4v2 has been dropped. Instead install additional FFmpeg packages to build Mixxx with FFmpeg enabled:

sudo apt-get install g++ git scons cmake ccache libportmidi-dev libopusfile-dev \
  libshout-dev libtag1-dev libprotobuf-dev protobuf-compiler \
  libusb-1.0-0-dev libfftw3-dev libmad0-dev portaudio19-dev \
  libchromaprint-dev librubberband-dev libsqlite3-dev \
  libid3tag0-dev libflac-dev libsndfile-dev libupower-glib-dev \
  libavcodec-dev libavformat-dev libavutil-dev libswresample-dev \
  libgl-dev liblilv-dev \
  libjack-dev libjack0 portaudio19-dev \
  libmp3lame-dev libebur128-dev qt5keychain-dev libmodplug-dev

And build with:

scons faad=0 ffmpeg=1

If you are building the Mixxx main or 2.3 git branch, additionally run:

sudo apt-get install qt5-default qt5keychain-dev qtdeclarative5-dev libqt5opengl5-dev qtscript5-dev libqt5svg5-dev libqt5x11extras5-dev libvamp-sdk2v5 libhidapi-libusb0 libqt5sql5-sqlite libmodplug-dev

If you are building Mixxx 2.2, additionally run:

sudo apt-get install qt5-default qtdeclarative5-dev libqt5opengl5-dev qtscript5-dev libqt5svg5-dev libqt5x11extras5-dev libqt5sql5-sqlite libmodplug-dev

If you are building Mixxx 2.1, additionally run:

sudo apt-get install libqt4-dev libqt4-sql-sqlite libqt4-opengl-dev libqt4-svg libqt4-xmlpatterns libqt4-sql

Fedora

On Fedora, enable the RPMFusion package repository. You only need to enable the free repository; the nonfree repository is not necessary for Mixxx. Then run:

sudo dnf groupinstall "Development Tools"
sudo dnf install gcc-c++ ccache lame-devel qt5-declarative-devel
sudo dnf builddep mixxx

Arch & Derivatives

If you are developing in Arch, you should have the base-devel group installed.

The tools you are going to need for working with Mixxx are:

sudo pacman -S --needed git gcc cmake

Alternatively, you can substitute gcc with clang.

Then install the dependencies:

sudo pacman -S --needed libid3tag libmad portaudio qt libogg \
    libvorbis libsndfile portmidi libmp4v2 faad2 libshout \
    taglib protobuf vamp-plugin-sdk rubberband \
    chromaprint sqlite upower lilv lame \
    soundtouch opusfile

Nix & NixOS

If you have the nix package manager installed (can be done on any Linux system), or you are running NixOS, getting started is the easiest.

Creating a release

nix-build shell.nix --arg releaseMode true --arg defaultLv2Plugins true

This will build a fully functional mixxx derivate to run at any time.

Development Environment

To get a working development environment start a nix-shell like this:

nix-shell --arg enableKeyfinder true --arg defaultLv2Plugins true

You can then use the commands configure, build, run, debug for your workcycle. The result will be placed in the folder cbuild. ccache is used inside the development shell to speed up your recompile times.

VSCode support

You can use following task for building mixxx inside the nix development environment and have proper error parsing:

{
    "label": "build",
    "type": "shell",
    "command": "nix-shell --arg enableKeyfinder true --arg defaultLv2Plugins true --command 'build;'",
    "options": {
        "cwd": "${workspaceFolder}"
    },
    "problemMatcher": {
        "base": "$gcc",
        "fileLocation": ["absolute"]
    },
    "group": {
        "kind": "build",
        "isDefault": true
    },
    "runOptions": { "instances": 1}
}

Non-system Qt

If your distribution's Qt package is older than the version required by Mixxx, download the latest Qt source code. For each Qt version, it is available at that link in a directory called "single" and has a filename like qt-everywhere-src-VERSION.tar.xz. Extract that archive and compile the source code:

tar xf qt-everywhere-src-VERSION.tar.xz
cd qt-everywhere-src-VERSION
./configure -prefix /path/to/qt/install -system-sqlite -sql-sqlite -qt-zlib -opensource -confirm-license -nomake examples -nomake tests -skip qt3d -skip qtwebengine
make -j`nproc`
make install

Other

For other distributions, you will need to install the following through your distribution's package manager. On most distributions, you will also need the corresponding -dev or -devel packages for each package. If you cannot find a package listed here that starts with "lib", try searching for the package name without the "lib" prefix.

• cmake
• libid3tag
• libmad
• PortAudio-v19
• Qt 5
• libogg, libvorbis, libvorbisfile
• libsndfile
• PortMidi & PortTime
• libmp4 (or libmp4v2) (optional, for M4A file support)

Download Mixxx source code

If you are still running as root from installing packages, return to using your normal unprivileged user account (press Ctrl + D or run exit).

Either download the source for the latest release from the downloads page on the website, or checkout a snapshot from our git repository:

• For the latest development (master) branch: git clone https://github.com/mixxxdj/mixxx.git
• For the latest stable branch: git clone -b <version> https://github.com/mixxxdj/mixxx.git

To update to the latest version of a git branch, enter (cd into) the directory you cloned the git repository into and run git pull. Refer to Using Git for more details.

Compile and install

CMake

Configure

Mixxx uses the CMake build system as of Mixxx 2.3. Building and installing Mixxx follows the standard CMake procedures.

To build with CMake, first create a new directory and enter it. This is typically under the project root, but it can be anywhere you want. This guide will assume you have the Mixxx source code in ~/mixxx. If you have it somewhere else, replace ~/mixxx with the path where the source code is.

mkdir ~/mixxx/build

Now configure CMake. This only needs to be done once; you don't need to repeat it when you compile Mixxx again. This step checks if you have all the dependencies installed, similar to the configure script of GNU autotools. /usr/local is used as the installation path in this example, but you can set this to anywhere as long as your $PATH environment variable includes a bin directory under the installation path (/usr/local/bin if the installation path is /usr/local). Don't use the prefix /usr, because it is reserved for packaged version of Mixxx (deb/rpm/...) and will interfere with the update process of you package manager.

cmake -DCMAKE_INSTALL_PREFIX=/usr/local -S ~/mixxx -B ~/mixxx/build

Compile Mixxx

cmake --build ~/mixxx/build --parallel `nproc`

Contrary to the behavior of the old SCons build system, CMake does not move the produced binaries into the root folder of the project.

Install Mixxx

If you want to compile and install in one step, you can skip the compilation step above and just run this command.

cmake --build ~/mixxx/build --target install --parallel `nproc`

Debug build

If you want to make a debug build, add -DCMAKE_BUILD_TYPE=Debug -DDEBUG_ASSERTIONS_FATAL=ON to the end of the cmake configure command. Debug builds should be started with the command line option --debugAssertBreak to trigger a breakpoint in the debugger if debug assertions are violated or to abort Mixxx immediately. This ensures that messages about violated debug assertions are not missed between various other debug log messages. We recommend this if you are working on Mixxx code, but not if you are performing with Mixxx.

ccache

We highly recommend installing CCache if you will be contributing code to Mixxx. If you won't be writing or testing code and are just building Mixxx to use it for yourself, you can skip installing CCache. CCache drastically speeds up the time to recompile Mixxx, especially when switching between git branches. CMake works with CCache automatically.

You will probably want to increase the default ccache size of 5.0GB to something much larger to accommodate Mixxx's large build sizes. You can adjust the cache size with the --set-config flag:

ccache --set-config=max_size=20.0G

Non-System-Qt

Append -DCMAKE_PREFIX_PATH=/path/to/qt/install (where /path/to/qt/install is the path you used when building Qt) to the cmake configure command to instruct cmake to prefer the Qt version from that path.

SCons

Mixxx 2.2 and earlier use the SCons build system. Mixxx 2.3 also supports SCons, but SCons support will be removed in Mixxx 2.4.

Once you have the source code, change to the newly created "mixxx" directory (run cd mixxx). Mixxx uses the SCons build system rather than the more common GNU autotools and GNU make. Running scons -h in the "mixxx" directory shows a complete list of build flags if you'd like to customize. To compile without any special options, as a regular user, run:

scons prefix=INSTALLATION_DIRECTORY -j `nproc` optimize=native

Change INSTALLATION_DIRECTORY to the location you want to install Mixxx to. If you want to install Mixxx for all users of the OS, you do not need to specify a prefix and can leave it as the default, which is /local. If you only want to install Mixxx for your user, you can specify a location in your home directory such as ~/local

Running scons will take some time, depending on the speed of your computer. Specifying NUMBER_OF_CPU_CORES will tell scons to run that many threads at a time while compiling. This speeds up compilation on multi-core CPUs. You can check how many threads your CPU can run simultaneously with the lscpu command (look for the CPU(s) field in the output). Setting more threads than your CPU can handle will decrease performance.

Once Mixxx has compiled, if you set the prefix options for scons to a directory that your normal user does not have write access to, run

sudo scons prefix=INSTALLATION_DIRECTORY install

to install it. If you set the prefix to a directory your user does have write access to, then you do not need sudo before scons. The prefix option must be the same as before or scons will recompile Mixxx before installing it.

If you want to be able to run Mixxx on different types of CPUs, change optimize=native to optimize=portable. If you want to contribute code to Mixxx and use a debugger, use optimize=off.

To compile on a Raspberry Pi (only compatible on Rapsberry Pi 3 and later), use the arguments: optimize=native machine=armhf with scons.

Debug build

To catch bugs early during development build and run Mixxx with the following options.

build=debug debug_assertions_fatal=1

Debug builds should be started with the command line option --debugAssertBreak to trigger a breakpoint in the debugger if debug assertions are violated or to abort Mixxx immediately. This ensures that messages about violated debug assertions are not missed between various other debug log messages. We recommend this if you are working on Mixxx code, but not if you are performing with Mixxx.

Optional: Build with m4a/AAC file support

If you want to play m4a files, add faad=1 to your scons commands above. This requires the libraries faad2 and libmp4v2 (or libmp4) to be installed.

Optional: Compile with Clang

Clang is a C/C++ compiler based on LLVM. Using Clang has various benefits:

• Better error messages
• Colorized compilation output
• Better tools for analyzing problems in your program ( Address Sanitizer, Thread Sanitizer, MemorySanitizer, etc.)

On Debian, Clang is provided as a package with a version number attached. Using 6.0 as an example, install it like this:

sudo apt-get install clang-6.0

To compile Mixxx using Clang 6.0, before running scons:

export CC=clang-6.0
export CXX=clang++-6.0

You can now use clang-specific SCons options.

• To enable colorized output, use the color=1 scons flag.
• To enable Address Sanitizer, use the asan=1 scons flag.

Troubleshooting scons

If scons can't find installed dependencies, try

scons --config=force

Uninstall

To uninstall a copy of Mixxx that you compiled with SCons, cd into the directory where you ran scons before, then run:

scons -c prefix=INSTALLATION_DIRECTORY install

INSTALLATION_DIRECTORY must be the same as that used when compiling and installing. If you needed to use sudo to install, also use sudo to uninstall.

Clean up

If scons fails with mysterious errors about not finding dependencies that you know are installed, it may be using outdated cached information to look for the dependencies. This can happen after upgrading your GNU/Linux distribution. To resolve this, try running scons -c and recompiling Mixxx.

Run without installing

If you want to run your compiled version without installing, from the same directory, run:

./mixxx --resourcePath res/ --settingsPath <folder>

You can omit the --settingsPath argument, but then mixxxx will use and potentially overwrite your user-wide configs.