diff --git a/pkgs/development/compilers/hhvm/default.nix b/pkgs/development/compilers/hhvm/default.nix
index 3a37ec13758..4159b7bd52b 100644
--- a/pkgs/development/compilers/hhvm/default.nix
+++ b/pkgs/development/compilers/hhvm/default.nix
@@ -35,7 +35,7 @@ stdenv.mkDerivation rec {
     })
   ];
 
-  enableParallelBuilding = false; # occasional build problems;
+  enableParallelBuilding = true;
   dontUseCmakeBuildDir = true;
   NIX_LDFLAGS = "-lpam -L${pam}/lib";
 
diff --git a/pkgs/top-level/all-packages.nix b/pkgs/top-level/all-packages.nix
index fec0743dabd..7e0cb81243a 100644
--- a/pkgs/top-level/all-packages.nix
+++ b/pkgs/top-level/all-packages.nix
@@ -5833,9 +5833,7 @@ with pkgs;
   haxePackages = recurseIntoAttrs (callPackage ./haxe-packages.nix { });
   inherit (haxePackages) hxcpp;
 
-  hhvm = callPackage ../development/compilers/hhvm {
-    boost = boost160;
-  };
+  hhvm = callPackage ../development/compilers/hhvm { };
 
   hop = callPackage ../development/compilers/hop { };