diff --git a/flake.nix b/flake.nix
index 43dc0e957..1d71dc429 100644
--- a/flake.nix
+++ b/flake.nix
@@ -471,8 +471,6 @@
                     # Disabled, as it doesn't currently build with Nix.
                     #weeder = weederVersion;
 
-                    fourmolu = fourmoluVersion;
-
                     cabal-fmt = "latest";
 
                     #TODO Explicitly requiring tasty-discover shouldn't be necessary - see the commented-out `build-tool-depends` in primer.cabal.