This is fork of ChromiumOS touch keyboard driver found at https://chromium.googlesource.com/chromiumos/platform2/+/19effa94d56d31397a55292771c8ea196f419f1e/touch_keyboard/
To get some details about the project, check the README.upstream.md file.
apt install build-essential cmake
mkdir build
cd build
cmake ../
make
sudo make install
Or just run the dpkg-buildpackage -b --no-sign
command to build .deb package.
To create custom keyboard layout, edit the file layout.csv and place it as /etc/touch_keyboard/layout.csv.