diff --git a/docs/_config.yml b/docs/_config.yml
index 11d18f0ac20939968302e99d071171a2f58d542c..ce0fdf5fb4f03d7cb7a2b31403cda4a32b0096a7 100644
--- a/docs/_config.yml
+++ b/docs/_config.yml
@@ -5,6 +5,6 @@ markdown: kramdown
 # of Spark, Scala, and Mesos.
 SPARK_VERSION: 0.9.0-incubating-SNAPSHOT
 SPARK_VERSION_SHORT: 0.9.0
-SCALA_VERSION: 2.10
+SCALA_VERSION: "2.10"
 MESOS_VERSION: 0.13.0
 SPARK_ISSUE_TRACKER_URL: https://spark-project.atlassian.net