Grep util when ?

[SimonDevStack]

[oech3]

grep is not coreutils. But there are uutils/util-linux,sed,tar,etc...

100% drop-in for GNU grep might difficult because we probally don't want to add new project depending on onig which was archived and no reasonable alts: rust-lang/regex#1126 (comment) .
But you might able to have shebang wrapper for rg.
@BurntSushi