You'll need the following dependencies:
- cmake
- libdevhelp-dev
- libgail-3-dev
- libgee-0.8-dev
- libgtksourceview-3.0-dev
- libgtkspell3-3-dev
- libgranite-dev
- libpeas-dev
- libsoup2.4-dev
- libvala-0.34-dev
- libvte-2.91-dev
- libwebkit2gtk-4.0-dev
- libzeitgeist-2.0
- valac
It's recommended to create a clean build environment
mkdir build
cd build/
Run cmake to configure the build environment and then make to build
cmake -DCMAKE_INSTALL_PREFIX=/usr ..
make
To install, use make install, then execute with io.elementary.code
sudo make install
io.elementary.code