diff --git a/t/test-lib.sh b/t/test-lib.sh
index 6f6244a..da12b0a 100644
--- a/t/test-lib.sh
+++ b/t/test-lib.sh
@@ -94,6 +94,8 @@
 	--no-python)
 		# noop now...
 		shift ;;
+	--va|--val|--valg|--valgr|--valgri|--valgrin|--valgrind)
+		valgrind=t; shift ;;
 	*)
 		break ;;
 	esac
@@ -492,8 +494,60 @@
 # Test the binaries we have just built.  The tests are kept in
 # t/ subdirectory and are run in 'trash directory' subdirectory.
 TEST_DIRECTORY=$(pwd)
-PATH=$TEST_DIRECTORY/..:$PATH
-GIT_EXEC_PATH=$(pwd)/..
+if test -z "$valgrind"
+then
+	PATH=$TEST_DIRECTORY/..:$PATH
+	GIT_EXEC_PATH=$TEST_DIRECTORY/..
+else
+	make_symlink () {
+		test -h "$2" &&
+		test "$1" = "$(readlink "$2")" || {
+			# be super paranoid
+			if mkdir "$2".lock
+			then
+				rm -f "$2" &&
+				ln -s "$1" "$2" &&
+				rm -r "$2".lock
+			else
+				while test -d "$2".lock
+				do
+					say "Waiting for lock on $2."
+					sleep 1
+				done
+			fi
+		}
+	}
+
+	make_valgrind_symlink () {
+		# handle only executables
+		test -x "$1" || return
+
+		base=$(basename "$1")
+		symlink_target=$TEST_DIRECTORY/../$base
+		# do not override scripts
+		if test -x "$symlink_target" &&
+		    test ! -d "$symlink_target" &&
+		    test "#!" != "$(head -c 2 < "$symlink_target")"
+		then
+			symlink_target=../valgrind.sh
+		fi
+		# create the link, or replace it if it is out of date
+		make_symlink "$symlink_target" "$GIT_VALGRIND/bin/$base" || exit
+	}
+
+	# override all git executables in TEST_DIRECTORY/..
+	GIT_VALGRIND=$TEST_DIRECTORY/valgrind
+	mkdir -p "$GIT_VALGRIND"/bin
+	for file in $TEST_DIRECTORY/../git* $TEST_DIRECTORY/../test-*
+	do
+		make_valgrind_symlink $file
+	done
+	PATH=$GIT_VALGRIND/bin:$PATH
+	GIT_EXEC_PATH=$GIT_VALGRIND/bin
+	export GIT_VALGRIND
+
+	make_symlink ../../../templates "$GIT_VALGRIND"/bin/templates || exit
+fi
 GIT_TEMPLATE_DIR=$(pwd)/../templates/blt
 unset GIT_CONFIG
 GIT_CONFIG_NOSYSTEM=1