diff --git a/pkgs/top-level/all-packages.nix b/pkgs/top-level/all-packages.nix
index 59dcde82652..b4f0d19878d 100644
--- a/pkgs/top-level/all-packages.nix
+++ b/pkgs/top-level/all-packages.nix
@@ -2663,19 +2663,19 @@ let
     inherit fetchurl stdenv aspell which;
   });
 
-  aterm = aterm28;
+  aterm = aterm242fixes;
 
   aterm242fixes = import ../development/libraries/aterm/2.4.2-fixes.nix {
     inherit fetchurl stdenv;
   };
 
-  aterm25 = import ../development/libraries/aterm/2.5.nix {
+  aterm25 = lowPrio (import ../development/libraries/aterm/2.5.nix {
     inherit fetchurl stdenv;
-  };
+  });
 
-  aterm28 = import ../development/libraries/aterm/2.8.nix {
+  aterm28 = lowPrio (import ../development/libraries/aterm/2.8.nix {
     inherit fetchurl stdenv;
-  };
+  });
 
   attr = useFromStdenv "attr"
     (import ../development/libraries/attr {