You'll need the following dependencies:
- gobject-introspection
- libecal1.2-dev
- libedataserver1.2-dev
- libical-dev
- libgranite-dev
- libwingpanel-2.0-dev
- meson
- valac >= 0.40.3
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