diff --git a/default.nix b/default.nix
index 85743b914393847fa8adc383ade8d394f06fa7cd..1a6a0ee4da75fbc7a7098f6881afc2e8e2ae4194 100644
--- a/default.nix
+++ b/default.nix
@@ -63,7 +63,7 @@ let
               inherit (self) lib;
               pkgs = self;
             };
-            buildHaskellPackages = haskellPackages;
+            buildHaskellPackages = self.buildPackages.haskell.packages.ghc865;
             ghc = ghcHEAD;
             compilerConfig = self1: super1: {
               # Packages included in GHC's global package database