diff --git a/xmonad.cabal b/xmonad.cabal
index 611dff5..53d4ca4 100644
--- a/xmonad.cabal
+++ b/xmonad.cabal
@@ -84,7 +84,11 @@ library
                  , setlocale
                  , unix
                  , utf8-string           >= 0.3 && < 1.1
-  ghc-options:     -funbox-strict-fields -Wall -fno-warn-unused-do-bind
+  ghc-options:     -funbox-strict-fields -Wall -fno-warn-unused-do-bind -Wno-unused-imports
+
+  -- Keep this in sync with the oldest version in 'tested-with'
+  if impl(ghc <= 8.4.4)
+     ghc-options: -Werror=unused-imports
 
   if flag(testing)
     buildable: False
@@ -92,7 +96,11 @@ library
 executable xmonad
   main-is:       Main.hs
   build-depends: base, X11, mtl, unix, xmonad
-  ghc-options:   -Wall -fno-warn-unused-do-bind
+  ghc-options:   -Wall -fno-warn-unused-do-bind -Wno-unused-imports
+
+  -- Keep this in sync with the oldest version in 'tested-with'
+  if impl(ghc <= 8.4.4)
+     ghc-options: -Werror=unused-imports
 
 executable generatemanpage
   main-is:        GenerateManpage.hs