diff --git a/Makefile b/Makefile
index 362d08d..a1dc5e0 100644
--- a/Makefile
+++ b/Makefile
@@ -1,5 +1,9 @@
+# HACK: sbt seems to ignore JAVA_HOME by default, force it to use the correct jdk.
+sbt      = sbt $(sbt_args)
+sbt_args = -java-home $(JAVA_HOME)
+
 run:
-	sbt run
+	$(sbt) run
 
 clean:
-	sbt clean
+	$(sbt) clean