How to install silversearcher-ag without sudo

This will install ag aka the silver searcher in your home directory ($HOME/usr), without needing sudo.

git clone -b 2.2.0 https://github.com/ggreer/the_silver_searcher.git
cd the_silver_searcher
./autogen.sh
./build.sh --prefix=$HOME/usr
make install

If you have $HOME/usr/bin in your $PATH, you can now use ag as usual.