1. Install dependencies
sudo apt-get install git autoconf automake xorg-dev graphicsmagick gv libmotif-dev libcurl4-openssl-dev build-essential shapelib libshp-dev festival festival-dev libgeotiff-dev libgraphicsmagick1-dev
2. Get the code
git clone https://github.com/Xastir/Xastir
3. run bootstrap script and create a build directory
cd Xastir
/bootstrap.sh
mkdir build
4. Build, compile and install
cd build
../configure
make
sudo make install