diff --git a/mk/check.mk b/mk/check.mk
index 9fcda7cd7ad..766815d755d 100644
--- a/mk/check.mk
+++ b/mk/check.mk
@@ -93,7 +93,7 @@ check-content: contenttest
 
 .PHONY: check-wpt
 check-wpt:
-	bash $(S)src/test/wpt/run.sh $(S)
+	bash $(S)src/test/wpt/run.sh $(S) $(B)
 
 .PHONY: tidy
 tidy:
diff --git a/src/test/wpt/run.sh b/src/test/wpt/run.sh
index b60b7c2a1fb..6b61c55af02 100644
--- a/src/test/wpt/run.sh
+++ b/src/test/wpt/run.sh
@@ -2,7 +2,7 @@
 # License, v. 2.0. If a copy of the MPL was not distributed with this
 # file, You can obtain one at http://mozilla.org/MPL/2.0/.
 
-cd $1/build
+cd $2
 
 test -d _virtualenv || virtualenv _virtualenv
 test -d $1/src/test/wpt/metadata || mkdir -p $1/src/test/wpt/metadata
@@ -10,4 +10,4 @@ test -d $1/src/test/wpt/prefs || mkdir -p $1/src/test/wpt/prefs
 source _virtualenv/bin/activate
 (python -c "import html5lib" &>/dev/null) || pip install html5lib
 (python -c "import wptrunner"  &>/dev/null) || pip install wptrunner
-python $1/src/test/wpt/run.py
+python $1/src/test/wpt/run.py --binary $2/../servo