This package FTBFS with newer versions of GHC (ghc-8.6.5) with the
following error:

Building executable 'werewolf' for werewolf-1.5.2.0..
[ 1 of 53] Compiling Game.Werewolf.Message ( app/Game/Werewolf/Message.hs, dist-ghc/build/werewolf/werewolf-tmp/Game/Werewolf/Message.o )
[ 2 of 53] Compiling Game.Werewolf.Variant.NoRoleKnowledge.Command ( app/Game/Werewolf/Variant/NoRoleKnowledge/Command.hs, dist-ghc/build/werewolf/werewolf-tmp/Game/Werewolf/Variant/NoRoleKnowledge/Command.o )
[ 3 of 53] Compiling Game.Werewolf.Variant.NoRoleKnowledge.Engine ( app/Game/Werewolf/Variant/NoRoleKnowledge/Engine.hs, dist-ghc/build/werewolf/werewolf-tmp/Game/Werewolf/Variant/NoRoleKnowledge/Engine.o )
[ 4 of 53] Compiling Game.Werewolf.Variant.NoRoleKnowledgeOrReveal.Command ( app/Game/Werewolf/Variant/NoRoleKnowledgeOrReveal/Command.hs, dist-ghc/build/werewolf/werewolf-tmp/Game/Werewolf/Variant/NoRoleKnowledgeOrReveal/Command.o )

app/Game/Werewolf/Variant/NoRoleKnowledgeOrReveal/Command.hs:56:31: error:
    • Parse error in expression!
    • In the quasi-quotation:
        [iFile|variant/no-role-knowledge-or-reveal/command/status/dead-players.txt|]
   |
56 | deadPlayersText game = [iFile|variant/no-role-knowledge-or-reveal/command/status/dead-players.txt|]
   |                               ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
make: *** [/usr/share/cdbs/1/class/hlibrary.mk:147: build-ghc-stamp] Error 1
dpkg-buildpackage: error: debian/rules binary subprocess returned exit status 2

Dear submitter,

as the package haskell-werewolf has just been removed from the Debian archive
unstable we hereby close the associated bug reports.  We are sorry
that we couldn't deal with your issue properly.

For details on the removal, please see https://bugs.debian.org/1011223

The version of this package that was in Debian prior to this removal
can still be found using http://snapshot.debian.org/.

Please note that the changes have been done on the master archive and
will not propagate to any mirrors until the next dinstall run at the
earliest.

This message was generated automatically; if you believe that there is
a problem with it please contact the archive administrators by mailing
ftpmaster@ftp-master.debian.org.

Debian distribution maintenance software
pp.
Thorsten Alteholz (the ftpmaster behind the curtain)