Looks like HaRe has been abandoned. The last commit here is from 2017. There are no build plans for GHC > 8.0.
I made this fact explicit via revisions, e.g.: https://hackage.haskell.org/package/HaRe-0.8.4.1/revisions/
Maybe you want to make this explicit by archiving this repo or flagging the unmaintained status prominently in the README.
Is there any follow-up project? I am interested in a tool to find clones in Haskell code bases...