Anmo

#!/bin/bash

#First create a repo
mkdir A && cd A && git init && touch a.dev && touch a.prod && git add -A && git commit -m 'init A' && cd ../

#Lets create another repo that will use A as submodule with sparse-checkout
mkdir B && cd B && git init && touch b && git add -A && git commit -m 'init B'

#Now we will clone A as submodule of B and will say that file/dir we only want to use in B
git submodule add ../A/ A && cd A && git config core.sparsecheckout true && echo a.prod >> ../.git/modules/A/info/sparse-checkout && git read-tree -mu HEAD && cd ../ && git add -A && git commit -m 'add A as submodule/sparse-checkout' && cd ../