For Ubuntu 22.04. Install conda and then create a new conda environment with python 3.8 and activate the env. Then install gfortran, git and pip3.8. Finally install Exostriker using its git repository via pip.
conda create --name py38 python=3.8 conda activate py38 sudo apt-get install gfortran sudo apt-get install git curl https://bootstrap.pypa.io/get-pip.py -o get-pip.py python3.8 get-pip.py pip3.8 install git+https://github.com/3fon3fonov/exostriker