diff --git a/build.gradle b/build.gradle
index d5d739e..bcc45e5 100644
--- a/build.gradle
+++ b/build.gradle
@@ -2,7 +2,7 @@ apply plugin: 'java'
 apply plugin: 'maven'
 
 group = "jupyter"
-version = '0.1.0'
+version = '0.2.1'
 
 repositories {
   mavenCentral()
diff --git a/src/main/java/jupyter/Displayer.java b/src/main/java/jupyter/Displayer.java
index 929278a..b1a177b 100644
--- a/src/main/java/jupyter/Displayer.java
+++ b/src/main/java/jupyter/Displayer.java
@@ -48,6 +48,6 @@ public abstract class Displayer<T> {
    *
    * @param types MIME types that are supported by the kernel
    */
-  void setMimeTypes(String... types) {
+  public void setMimeTypes(String... types) {
   }
 }
diff --git a/src/test/java/jupyter/TestMimeTypeNotification.java b/src/test/java/jupyter/TestMimeTypeNotification.java
index 0c1df02..a069d4b 100644
--- a/src/test/java/jupyter/TestMimeTypeNotification.java
+++ b/src/test/java/jupyter/TestMimeTypeNotification.java
@@ -52,7 +52,7 @@ public Map<String, String> display(String obj) {
     }
 
     @Override
-    void setMimeTypes(String... types) {
+    public void setMimeTypes(String... types) {
       mimeTypes = new HashSet<>(Arrays.asList(types));
     }
   }