diff --git a/pkgs/tools/compression/lz4/default.nix b/pkgs/tools/compression/lz4/default.nix
index 26e82886b6f..d27ada615c7 100644
--- a/pkgs/tools/compression/lz4/default.nix
+++ b/pkgs/tools/compression/lz4/default.nix
@@ -11,8 +11,7 @@ stdenv.mkDerivation rec {
     owner = "Cyan4973";
   };
 
-  # valgrind is required only by `make test`
-  buildInputs = [ valgrind ];
+  buildInputs = stdenv.lib.optional doCheck valgrind;
 
   enableParallelBuilding = true;
 
diff --git a/pkgs/tools/compression/xdelta/default.nix b/pkgs/tools/compression/xdelta/default.nix
index 11d7004d959..fcc3b373fd1 100644
--- a/pkgs/tools/compression/xdelta/default.nix
+++ b/pkgs/tools/compression/xdelta/default.nix
@@ -1,7 +1,7 @@
 { stdenv, fetchFromGitHub, autoreconfHook }:
 
 let version = "3.0.9"; in
-stdenv.mkDerivation {
+stdenv.mkDerivation rec {
   name = "xdelta-${version}";
   
   src = fetchFromGitHub {
@@ -15,7 +15,7 @@ stdenv.mkDerivation {
 
   postPatch = ''
     cd xdelta3
-
+  '' + stdenv.lib.optionalString doCheck ''
     mkdir tmp
     substituteInPlace testing/file.h --replace /tmp tmp
     substituteInPlace xdelta3-test.h --replace /tmp $PWD/tmp