ripgrep aka rg provides great defaults to search inside files.
It automatically skip .git directories and files ignored by git reducing the amount of data being searched.
These are sane defaults to have and can safe you a lot of development time.
Searching for the same word inside the same directory gives me this.
time rg -li 'pattern'
real 0m17.514s user 0m15.610s sys 0m8.822s
time grep -ilR 'pattern'
real 1m9.520s user 0m29.768s sys 0m8.352s