Installation

Tools and library dependencies

ryujin requires deal.II version 9.6.0 or newer, compiled with support enabled for MPI and P4est.

Debian

On Debian 13 (trixie) or newer, run the following as root to install deal.II, all development libraries, and the necessary tools:

apt install libdeal.ii-dev cmake cmake-curses-gui numdiff make g++ ninja-build git

Ubuntu

On Ubuntu LTS 26.04, run:

sudo apt install libdeal.ii-dev cmake cmake-curses-gui numdiff make g++ ninja-build git

Ubuntu LTS 24.04 and LTS 22.04 ship deal.II 9.5.1 and 9.3.2, which are too old. Add the deal.II 9.7.1 backports PPA first, then install the same packages:

sudo apt install software-properties-common
sudo add-apt-repository ppa:ginggs/deal.ii-9.7.1-backports
sudo apt update
sudo apt install libdeal.ii-dev cmake cmake-curses-gui numdiff make g++ ninja-build git

The deal.II download page lists PPAs for other deal.II releases.

macOS

The simplest route is the precompiled macOS bundle for deal.II, available from the deal.II GitHub download page.

Windows

We strongly recommend setting up the Windows Subsystem for Linux v2 (WSL) and installing Ubuntu LTS 26.04 from the Microsoft Store. Launch the Ubuntu app, which starts a Bash shell, and follow the Ubuntu instructions above.

If the Linux command line is new to you, this tutorial is a good starting point.

Generic instructions for downloading, installing, or manually compiling deal.II are on the deal.II homepage and the deal.II wiki. Make sure deal.II is configured with MPI and P4est support, and that git, numdiff, cmake and make are in your PATH.

Retrieving and compiling ryujin

With deal.II and the command line tools installed, check out the repository and run make:

1. Clone the repository and fetch its submodules:

   git clone https://github.com/conservation-laws/ryujin
   cd ryujin
   git submodule init
   git submodule update

2. Compile a release build:

   make release

3. The executable is now at build/run/ryujin.

ryujin uses the CMake build system. The Makefile in the repository holds a handful of convenience targets and its use is entirely optional; when invoked it creates a build subdirectory, runs cmake to configure the project, and builds it.

Target	Effect
make debug	Switch to a debug build and compile
make release	Switch to a release build and compile
make edit_cache	Run ccmake in the build directory

See Usage for running the solver, and Compile-time options for tuning the build.