diff --git a/.travis.yml b/.travis.yml
index 75b4211..c37e4ed 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -33,6 +33,7 @@ env:
   - SCALA_VERSION=2.12.1
   - SCALA_VERSION=2.12.2
   - SCALA_VERSION=2.12.3
+  - SCALA_VERSION=2.12.4
   - SCALA_VERSION=2.13.0-M2
 
 # there's no better way it seems.. https://github.com/travis-ci/travis-ci/issues/1519
@@ -47,6 +48,8 @@ matrix:
       env: SCALA_VERSION=2.12.2
     - jdk: openjdk6
       env: SCALA_VERSION=2.12.3
+    - jdk: openjdk6
+      env: SCALA_VERSION=2.12.4
     - jdk: openjdk6
       env: SCALA_VERSION=2.13.0-M2
 
diff --git a/build.sbt b/build.sbt
index 33a0231..c98d27e 100644
--- a/build.sbt
+++ b/build.sbt
@@ -51,7 +51,7 @@ lazy val defaults = Seq(
   scalaVersion := crossScalaVersions.value.last,
   crossScalaVersions := {
     val latest211 = 11
-    val latest212 = 3
+    val latest212 = 4
     val pre213 = List("M2")
     val skipVersions = Set("2.11.9", "2.11.10")
     val scala211Versions =
diff --git a/plugin/src/test/resources/patches/2.12.4.patch b/plugin/src/test/resources/patches/2.12.4.patch
new file mode 100644
index 0000000..7d6008c
--- /dev/null
+++ b/plugin/src/test/resources/patches/2.12.4.patch
@@ -0,0 +1,53 @@
+--- target/expected_output/basic/akka/rk/buh/is/it/A.java
++++ target/expected_output/basic/akka/rk/buh/is/it/A.java
+@@ -48,13 +48,13 @@
+     public  class NonStatic {
+       public   NonStatic ()  { throw new RuntimeException(); }
+     }
++    public  akka.rk.buh.is.it.A.D$.E$ E ()  { throw new RuntimeException(); }
+     public   D$ ()  { throw new RuntimeException(); }
+     /**
+      * def A.D.math
+      * @return (undocumented)
+      */
+     public  long math ()  { throw new RuntimeException(); }
+-    public  akka.rk.buh.is.it.A.D$.E$ E ()  { throw new RuntimeException(); }
+   }
+   /**
+    * class A.B
+@@ -94,12 +94,12 @@
+     public  class C1$ {
+       public   C1$ ()  { throw new RuntimeException(); }
+     }
+-    public   C1 ()  { throw new RuntimeException(); }
+     /**
+      * Accessor for nested Scala object
+      * @return (undocumented)
+      */
+     public  akka.rk.buh.is.it.A.C1.C1$ C1 ()  { throw new RuntimeException(); }
++    public   C1 ()  { throw new RuntimeException(); }
+   }
+   /**
+    * object C1
+@@ -147,6 +147,11 @@
+   static public  java.lang.String stattic ()  { throw new RuntimeException(); }
+   static public  java.lang.Object x ()  { throw new RuntimeException(); }
+   /**
++   * Accessor for nested Scala object
++   * @return (undocumented)
++   */
++  public  akka.rk.buh.is.it.A.D$ D ()  { throw new RuntimeException(); }
++  /**
+    * varargs
+    * @param s (undocumented)
+    * @return (undocumented)
+@@ -219,9 +224,4 @@
+    */
+   public  int testthrows () throws java.lang.IllegalArgumentException, java.lang.NullPointerException { throw new RuntimeException(); }
+   public  scala.runtime.Null$ getNull ()  { throw new RuntimeException(); }
+-  /**
+-   * Accessor for nested Scala object
+-   * @return (undocumented)
+-   */
+-  public  akka.rk.buh.is.it.A.D$ D ()  { throw new RuntimeException(); }
+ }