*Fresh Debian Install *
Sudo apt-get install ninja-build gettext libtool libtool-bin autoconf automake cmake g++ pkg-config unzip doxygen -y
git clone https://github.com/neovim/neovim
cd neovim && make
make install
sudo make install
cd ..
rm -rf neovim
existing neovim source
$cd neovim
$rm -rf .deps/
$rm -rf builds/
$git pull
$make
$sudo make install