Hgrep is a project mainly written in HASKELL and SHELL, it's free.
Haskell grep -r . implementation
grep -r .this is implementation of grep -r . function in haskell.
This is just to play a bit with haskell IO and find out if haskell native code can be faster then grep -r or zargs **.
It is not optimal yet.
to build this just run ./build.sh and you will have hgrep in bin folder