diff --git a/scripts/run-tut.sh b/scripts/run-tut.sh
index ad51ea6260..17a6299e03 100755
--- a/scripts/run-tut.sh
+++ b/scripts/run-tut.sh
@@ -2,5 +2,4 @@
 
 COURSIER_CLASSPATH="$(./coursier fetch -p com.chuusai:shapeless_2.11:2.3.1 org.scala-lang.modules::scala-xml:1.0.3)"
 
-./coursier launch -r "https://dl.bintray.com/tpolecat/maven/" org.tpolecat:tut-core_2.11:0.4.4 -- . tut-tmp '.*\.md$' -classpath "$COURSIER_CLASSPATH"
-
+./coursier launch -r "https://dl.bintray.com/tpolecat/maven/" org.tpolecat:tut-core_2.11:0.4.4 -- . tut-tmp '.*\.md$' -classpath "$COURSIER_CLASSPATH" -Xfatal-warnings -feature
diff --git a/tutorials/tour/implicit-conversions.md b/tutorials/tour/implicit-conversions.md
index aa53946c5c..71db42e38a 100644
--- a/tutorials/tour/implicit-conversions.md
+++ b/tutorials/tour/implicit-conversions.md
@@ -17,7 +17,7 @@ Implicit conversions are applied in two situations:
 * If an expression `e` is of type `S`, and `S` does not conform to the expression's expected type `T`.
 * In a selection `e.m` with `e` of type `T`, if the selector `m` does not denote a member of `T`.
 
-In the first case, a conversion `c` is searched for which is applicable to `e` and whose result type conforms to `T`. 
+In the first case, a conversion `c` is searched for which is applicable to `e` and whose result type conforms to `T`.
 In the second case, a conversion `c` is searched for which is applicable to `e` and whose result contains a member named `m`.
 
 The following operation on the two lists xs and ys of type `List[Int]` is legal:
@@ -33,7 +33,7 @@ implicit def list2ordered[A](x: List[A])
     (implicit elem2ordered: A => Ordered[A]): Ordered[List[A]] =
   new Ordered[List[A]] { /* .. */ }
 
-implicit def int2ordered(x: Int): Ordered[Int] = 
+implicit def int2ordered(x: Int): Ordered[Int] =
   new Ordered[Int] { /* .. */ }
 ```
 
@@ -42,6 +42,8 @@ The implicitly imported object `scala.Predef` declares several predefined types
 For example, when calling a Java method that expects a `java.lang.Integer`, you are free to pass it a `scala.Int` instead. That's because Predef includes the following implicit conversions:
 
 ```tut
+import scala.language.implicitConversions
+
 implicit def int2Integer(x: Int) =
   java.lang.Integer.valueOf(x)
 ```