You'll need the following dependencies:
- libaccountsservice-dev
- libibus-1.0-dev
- libgnome-desktop-3-dev
- libgranite-dev
- libswitchboard-2.0-dev
- meson >= 0.46.1
- policykit-1
- valac
Run meson to configure the build environment and then ninja to build
meson build --prefix=/usr
cd build
ninja
To install, use ninja install
sudo ninja install