ARCH=$(uname -m)
PYTHON="3.5.2"
curl -L https://raw.githubusercontent.com/yyuu/pyenv-installer/master/bin/pyenv-installer | bash
apt-get install -y libssl-dev libacl1-dev liblz4-dev libfuse-dev fuse pkg-config
apt-get install -y fakeroot build-essential git
apt-get install -y zlib1g-dev libbz2-dev libncurses5-dev libreadline-dev liblzma-dev libsqlite3-dev
env PYTHON_CONFIGURE_OPTS="--enable-shared" pyenv install -v $PYTHON
pyenv shell $PYTHON
cd /opt
git clone https://github.com/borgbackup/borg/
cd borg
git checkout 1.0.3
pip install -r requirements.d/development.txt
cd /opt
git clone https://github.com/pyinstaller/pyinstaller.git
cd pyinstaller
git checkout v3.1.1
cd bootloader
python ./waf all --no-lsb
cd ..
pip install -e .
cd /opt/borg
pip install -e .
LD_LIBRARY_PATH=~/.pyenv/versions/$PYTHON/lib/ pyinstaller -F -n borg-$ARCH --clean borg/__main__.py

Credits: bauerj‘s comment on https://github.com/borgbackup/borg/issues/1018