Building From Source (for dummies)

Here's how I got it to build-- this is non-optimal, but it works:

Debian Sid:

apt-get install build-essential qt5-default git cmake kdelibs5-dev
apt-get build-dep krita
mkdir ~/code
cd ~/code
git clone https://github.com/callaa/Drawpile.git
cd Drawpile
mkdir build
cd build
cmake ..
make
sudo make install

If you're building Qt, want to make the debug build, or only build the server, use cmake options:
cmake -DCLIENT=off -DCMAKE_PREFIX_PATH=/usr/local/Qt-5.3.1 -DCMAKE_INSTALL_RPATH:STRING="/usr/local/Qt-5.3.1/lib" -DCMAKE_BUILD_TYPE=debug ..