flatpak --user install flathub org.kde.Sdk/x86_64/5.12 # required SDK version might be higher, check the manifest at https://github.com/flathub/website.i2pd.i2pd/blob/master/website.i2pd.i2pd.json
flatpak --user install flathub org.kde.Sdk/x86_64/5.14 # required SDK version might be higher, check the manifest at https://github.com/flathub/website.i2pd.i2pd/blob/master/website.i2pd.i2pd.json
git clone https://github.com/flathub/website.i2pd.i2pd && cd website.i2pd.i2pd
export FLATPAK_BUILDER_N_JOBS=4 # build process jobs count