Custom cracking algorithm

Hello forum members , 

I am new here. I was playing with hashcat and its really interesting the way it cracks a hash. I want to ask if its possible to supply hashcat with a custom written script in c or any other language to perform some steps. Or if its possible to pipe output of one command into another hashcat instance. 

I am trying to crack hash generated from sha256 hash of md5 hash of a string.

Hopefully its possible. Doesnt matter even if it takes millions of years as i am going to try it on known input and output mixed in a million other strings. Just to test its capability.

Thanks