Installation Instructions

Short Version

First, you will need to install julia (see below for instructions).

Create a folder to hold your julia ACE project, and cd into the fodler. This folder will track the packages and versions which the ACE1pack code requires. For example:

mkdir ~/ACE1project
cd ~/ACE1project

From within this folder type julia to enter the Julia REPL. Then run

using Pkg; Pkg.activate("."); pkg"registry add"; pkg"registry add"; pkg"add ACE1pack, ACE1, JuLIP, IPFitting, ASE"

Before working on an ACE1 project in the ACE1project folder you will need to activate the Julia environment you just created in that folder. This can be done by starting julia with julia --project=pathtoproject, or from the package manager, or by exporting the environment variable JULIA_PROJECT set to the path to this folder. For example, export JULIA_PROJECT=~/ACE1project. <!– You can add this to your .bashrc/.bash_profile and not touch it again. –>

Setting up the Python ASE calculator

We use a wrapper called pyjulip to call julia and evaluate ACE potentials. In a terminal, with the correct julia project and python environment selected, run the following code:

python -m pip install julia
python -c "import julia; julia.install()"

Make sure to use the correct python and pip, e.g. the ones that are in the correct Conda environment. Then, to set up pyjulip:

git clone
cd pyjulip
pip install .

Detailed Instructions

If you have any difficulties with the following setup process, please file an issue. We highly recommend familiarizing oneself with the Julia package manager and how Project management is best done in Julia (there is also a summary in this section of these docs). In particular all projects should manage their own Project.toml file with appropriate version bounds, and where appropriate the Manifest.toml file can be tracked in order to guarantee reproducibility of results.

Installing Julia

Download and unpack Julia. We recommend v1.6 or upwards. Add the julia executable to your path with something like export PATH=<julia-directory>/bin:$PATH.

Start the Julia REPL (type julia followed by Enter), switch to package manager by typing ], then install the General registry and the MolSim registry:

registry add
registry add

Press Backspace or Ctrl-c to exit the package manager. Use Ctrl-d, or exit() followed by Enter, to close the Julia REPL.

Setting up a new ACE1.jl project

Create a folder for your new project and change to it. Start the Julia REPL and activate a new project by switching to the package manager with ], and then running

activate .

Now you can install ACE1pack. Remaining in the package manager, use

add ACE1pack

you will also need to add the following packages: ACE1, JuLIP, IPFitting, ASE.

Returning to a project

When returning to a project, there are several methods for reactivating it. One is to simply activate . in the package manager, as above. Alternatively set the JULIA_PROJECT environment variable to the directory with Project.toml before starting julia, or call julia as julia --project=<dir>. Special syntax like JULIA_PROJECT=@. or julia --project=@. searches the current directory and its parents for a Project.toml file.


  • On some systems ASE.jl (a dependency of IPFitting.jl) is unable to automatically install python dependencies. We found that installing Anaconda and then pointing PyCall.jl to the Anaconda installation (cf PyCall Readme) resolves this. After installing Anaconda, it should then be sufficient to build ASE.jl again.
  • If you cannot use Anaconda python, or if the last point failed, then you can try to install the python dependencies manually before trying to build ASE.jl again. Specifically, it should be sufficient to just install the ase package. Please follow the installation instructions on their website.