diff --git a/.scalafix.conf b/.scalafix.conf
index 21d1adb27d..37456749c4 100644
--- a/.scalafix.conf
+++ b/.scalafix.conf
@@ -4,6 +4,7 @@ rules = [
   ExplicitResultTypes
   "github:ohze/scalafix-rules/ConstructorProcedureSyntax"
   "github:ohze/scalafix-rules/FinalObject"
+  "github:ohze/scalafix-rules/Any2StringAdd"
 ]
 ExplicitResultTypes {
   memberVisibility = [] # only rewrite implicit members
diff --git a/akka-actor-tests/src/test/scala/akka/actor/DeathWatchSpec.scala b/akka-actor-tests/src/test/scala/akka/actor/DeathWatchSpec.scala
index 9ac9ad1dbc..1ed59028f9 100644
--- a/akka-actor-tests/src/test/scala/akka/actor/DeathWatchSpec.scala
+++ b/akka-actor-tests/src/test/scala/akka/actor/DeathWatchSpec.scala
@@ -83,7 +83,7 @@ trait DeathWatchSpec { this: AkkaSpec with ImplicitSender with DefaultTimeout =>
 
   "The Death Watch" must {
     def expectTerminationOf(actorRef: ActorRef) =
-      expectMsgPF(5 seconds, actorRef + ": Stopped or Already terminated when linking") {
+      expectMsgPF(5 seconds, "" + actorRef + ": Stopped or Already terminated when linking") {
         case WrappedTerminated(Terminated(`actorRef`)) => true
       }
 
diff --git a/akka-actor-tests/src/test/scala/akka/pattern/AskSpec.scala b/akka-actor-tests/src/test/scala/akka/pattern/AskSpec.scala
index 17e248bc2d..cc89300f5d 100644
--- a/akka-actor-tests/src/test/scala/akka/pattern/AskSpec.scala
+++ b/akka-actor-tests/src/test/scala/akka/pattern/AskSpec.scala
@@ -30,7 +30,7 @@ class AskSpec extends AkkaSpec {
       f.isCompleted should ===(true)
       f.value.get match {
         case Failure(_: AskTimeoutException) =>
-        case v                               => fail(v + " was not Failure(AskTimeoutException)")
+        case v                               => fail("" + v + " was not Failure(AskTimeoutException)")
       }
     }
 
@@ -41,7 +41,7 @@ class AskSpec extends AkkaSpec {
       f.isCompleted should ===(true)
       f.value.get match {
         case Failure(_: AskTimeoutException) =>
-        case v                               => fail(v + " was not Failure(AskTimeoutException)")
+        case v                               => fail("" + v + " was not Failure(AskTimeoutException)")
       }
     }
 
diff --git a/akka-actor/src/main/scala/akka/dispatch/AbstractDispatcher.scala b/akka-actor/src/main/scala/akka/dispatch/AbstractDispatcher.scala
index 2a33402175..0d765ce551 100644
--- a/akka-actor/src/main/scala/akka/dispatch/AbstractDispatcher.scala
+++ b/akka-actor/src/main/scala/akka/dispatch/AbstractDispatcher.scala
@@ -75,7 +75,7 @@ private[akka] object MessageDispatcher {
     if (debug) {
       for {
         d <- actors.keys
-        a <- { println(d + " inhabitants: " + d.inhabitants); actors.valueIterator(d) }
+        a <- { println("" + d + " inhabitants: " + d.inhabitants); actors.valueIterator(d) }
       } {
         val status = if (a.isTerminated) " (terminated)" else " (alive)"
         val messages = a match {
diff --git a/akka-actor/src/main/scala/akka/dispatch/Mailbox.scala b/akka-actor/src/main/scala/akka/dispatch/Mailbox.scala
index 26f4e058b5..701ba4981e 100644
--- a/akka-actor/src/main/scala/akka/dispatch/Mailbox.scala
+++ b/akka-actor/src/main/scala/akka/dispatch/Mailbox.scala
@@ -265,7 +265,7 @@ private[akka] abstract class Mailbox(val messageQueue: MessageQueue)
     if (shouldProcessMessage) {
       val next = dequeue()
       if (next ne null) {
-        if (Mailbox.debug) println(actor.self + " processing message " + next)
+        if (Mailbox.debug) println("" + actor.self + " processing message " + next)
         actor.invoke(next)
         if (Thread.interrupted())
           throw new InterruptedException("Interrupted while processing actor messages")
@@ -289,7 +289,7 @@ private[akka] abstract class Mailbox(val messageQueue: MessageQueue)
       val msg = messageList.head
       messageList = messageList.tail
       msg.unlink()
-      if (debug) println(actor.self + " processing system message " + msg + " with " + actor.childrenRefs)
+      if (debug) println("" + actor.self + " processing system message " + msg + " with " + actor.childrenRefs)
       // we know here that systemInvoke ensures that only "fatal" exceptions get rethrown
       actor.systemInvoke(msg)
       if (Thread.interrupted())
@@ -468,7 +468,7 @@ private[akka] trait DefaultSystemMessageQueue { self: Mailbox =>
   @tailrec
   final def systemEnqueue(receiver: ActorRef, message: SystemMessage): Unit = {
     assert(message.unlinked)
-    if (Mailbox.debug) println(receiver + " having enqueued " + message)
+    if (Mailbox.debug) println("" + receiver + " having enqueued " + message)
     val currentList = systemQueueGet
     if (currentList.head == NoMessage) {
       if (actor ne null) actor.dispatcher.mailboxes.deadLetterMailbox.systemEnqueue(receiver, message)
diff --git a/akka-remote/src/test/scala/akka/remote/classic/RemotingSpec.scala b/akka-remote/src/test/scala/akka/remote/classic/RemotingSpec.scala
index 35a06d74a4..7e1ec4afa0 100644
--- a/akka-remote/src/test/scala/akka/remote/classic/RemotingSpec.scala
+++ b/akka-remote/src/test/scala/akka/remote/classic/RemotingSpec.scala
@@ -226,7 +226,7 @@ class RemotingSpec extends AkkaSpec(RemotingSpec.cfg) with ImplicitSender with D
     "support ask" in {
       Await.result(here ? "ping", timeout.duration) match {
         case ("pong", _: akka.pattern.PromiseActorRef) => // good
-        case m                                         => fail(m + " was not (pong, AskActorRef)")
+        case m                                         => fail("" + m + " was not (pong, AskActorRef)")
       }
     }
 
diff --git a/akka-testkit/src/main/scala/akka/testkit/CallingThreadDispatcher.scala b/akka-testkit/src/main/scala/akka/testkit/CallingThreadDispatcher.scala
index 41b90be549..06381cf045 100644
--- a/akka-testkit/src/main/scala/akka/testkit/CallingThreadDispatcher.scala
+++ b/akka-testkit/src/main/scala/akka/testkit/CallingThreadDispatcher.scala
@@ -276,7 +276,7 @@ class CallingThreadDispatcher(_configurator: MessageDispatcherConfigurator) exte
         }
         if (handle ne null) {
           try {
-            if (Mailbox.debug) println(mbox.actor.self + " processing message " + handle)
+            if (Mailbox.debug) println("" + mbox.actor.self + " processing message " + handle)
             mbox.actor.invoke(handle)
             intex = checkThreadInterruption(intex)
             true