Building WarpX with support for openPMD output

WarpX can dump data in the openPMD format. This feature currently requires to have a parallel version of HDF5 installed ; therefore we recommend to use spack in order to facilitate the installation.

More specifically, we recommend that you try installing the openPMD-api library 0.15.1 or newer using spack (first section below). If this fails, a back-up solution is to install parallel HDF5 with spack, and then install the openPMD-api library from source.

In order to install spack, you can simply do:

git clone
export SPACK_ROOT=$PWD/spack
. $SPACK_ROOT/share/spack/

You may want to auto-activate spack when you open a new terminal by adding this to your $HOME/.bashrc file:

echo -e "# activate spack package manager\n. ${SPACK_ROOT}/share/spack/" >> $HOME/.bashrc

WarpX Development Environment with Spack

Create and activate a Spack environment with all software needed to build WarpX

spack env create warpx-dev    # you do this once
spack env activate warpx-dev
spack add gmake
spack add mpi
spack add openpmd-api
spack add pkg-config
spack install

This will download and compile all dependencies.

Whenever you need this development environment in the future, just repeat the quick spack env activate warpx-dev step. For example, we can now compile WarpX by cd-ing into the WarpX folder and typing:

spack env activate warpx-dev

You will also need to load the same spack environment when running WarpX, for instance:

spack env activate warpx-dev
mpirun -np 4 ./warpx.exe inputs

You can check which Spack environments exist and if one is still active with

spack env list  # already created environments
spack env st    # is an environment active?

Installing openPMD-api from source

You can also build openPMD-api from source, e.g. to build against the module environment of a supercomputer cluster.

First, load the according modules of the cluster to support the openPMD-api dependencies. You can find the required and optional dependencies here.

You usually just need a C++ compiler, CMake, and one or more file backend libraries, such as HDF5 and/or ADIOS2.

If optional dependencies are installed in non-system paths, one needs to hint their installation location with an environment variable during the build phase:

# optional: only if you manually installed HDF5 and/or ADIOS2 in custom directories
export HDF5_ROOT=$HOME/path_to_installed_software/hdf5-1.12.0/
export ADIOS2_ROOT=$HOME/path_to_installed_software/adios2-2.7.1/

Then, in the $HOME/warpx_directory/, download and build openPMD-api:

git clone
mkdir openPMD-api-build
cd openPMD-api-build
cmake --build . --target install

Finally, compile WarpX:

cd ../WarpX
# Note that one some systems, /lib might need to be replaced with /lib64.
export PKG_CONFIG_PATH=$HOME/warpx_directory/openPMD-install/lib/pkgconfig:$PKG_CONFIG_PATH
export CMAKE_PREFIX_PATH=$HOME/warpx_directory/openPMD-install:$CMAKE_PREFIX_PATH



If you compile with CMake, all you need to add is the -DWarpX_OPENPMD=ON option (on by default), and we will download and build openPMD-api on-the-fly.

When running WarpX, we will recall where you installed openPMD-api via RPATHs, so you just need to load the same module environment as used for building (same MPI, HDF5, ADIOS2, for instance).

# module load ...  (compiler, MPI, HDF5, ADIOS2, ...)

mpirun -np 4 ./warpx.exe inputs