diff --git a/compile/inc/src/main/scala/sbt/inc/Incremental.scala b/compile/inc/src/main/scala/sbt/inc/Incremental.scala
index 5966ea52d..db2cff86e 100644
--- a/compile/inc/src/main/scala/sbt/inc/Incremental.scala
+++ b/compile/inc/src/main/scala/sbt/inc/Incremental.scala
@@ -20,6 +20,12 @@ import java.io.File
  * - IncrementalAnyStyle
  */
 object Incremental {
+  class PrefixingLogger(val prefix: String)(orig: Logger) extends Logger {
+    def trace(t: => Throwable): Unit = orig.trace(t)
+    def success(message: => String): Unit = orig.success(message)
+    def log(level: sbt.Level.Value, message: => String): Unit = orig.log(level, message.replaceAll("(?m)^", prefix))
+  }
+
   /**
    * Runs the incremental compiler algorithm.
    *
@@ -45,7 +51,7 @@ object Incremental {
     {
       val incremental: IncrementalCommon =
         if (options.nameHashing)
-          new IncrementalNameHashing(log, options)
+          new IncrementalNameHashing(new PrefixingLogger("[naha] ")(log), options)
         else if (options.antStyle)
           new IncrementalAntStyle(log, options)
         else
diff --git a/compile/inc/src/main/scala/sbt/inc/IncrementalCommon.scala b/compile/inc/src/main/scala/sbt/inc/IncrementalCommon.scala
index e11939285..e38c68e2c 100644
--- a/compile/inc/src/main/scala/sbt/inc/IncrementalCommon.scala
+++ b/compile/inc/src/main/scala/sbt/inc/IncrementalCommon.scala
@@ -22,7 +22,8 @@ private[inc] abstract class IncrementalCommon(log: Logger, options: IncOptions)
     if (invalidatedRaw.isEmpty)
       previous
     else {
-      def debug(s: => String) = if (incDebug(options)) log.debug(s) else ()
+      val wrappedLog = new Incremental.PrefixingLogger("[inv] ")(log)
+      def debug(s: => String) = if (incDebug(options)) wrappedLog.debug(s) else ()
       val withPackageObjects = invalidatedRaw ++ invalidatedPackageObjects(invalidatedRaw, previous.relations)
       val invalidated = expand(withPackageObjects, allSources)
       val pruned = Incremental.prune(invalidated, previous, classfileManager)
@@ -64,23 +65,23 @@ private[inc] abstract class IncrementalCommon(log: Logger, options: IncOptions)
     newAPIMapping: T => Source): Unit = {
     val contextSize = options.apiDiffContextSize
     try {
+      val wrappedLog = new Incremental.PrefixingLogger("[diff] ")(log)
       val apiDiff = new APIDiff
       apiChanges foreach {
         case APIChangeDueToMacroDefinition(src) =>
-          log.debug(s"Public API is considered to be changed because $src contains a macro definition.")
+          wrappedLog.debug(s"Public API is considered to be changed because $src contains a macro definition.")
         case apiChange @ (_: SourceAPIChange[T] | _: NamesChange[T]) =>
           val src = apiChange.modified
           val oldApi = oldAPIMapping(src)
           val newApi = newAPIMapping(src)
           val apiUnifiedPatch = apiDiff.generateApiDiff(src.toString, oldApi.api, newApi.api, contextSize)
-          log.debug(s"Detected a change in a public API (${src.toString}):\n"
-            + apiUnifiedPatch)
+          wrappedLog.debug(s"Detected a change in a public API ($src):\n$apiUnifiedPatch")
       }
     } catch {
       case e: ClassNotFoundException =>
         log.error("You have api debugging enabled but DiffUtils library cannot be found on sbt's classpath")
       case e: LinkageError =>
-        log.error("Encoutared linkage error while trying to load DiffUtils library.")
+        log.error("Encountered linkage error while trying to load DiffUtils library.")
         log.trace(e)
       case e: Exception =>
         log.error("An exception has been thrown while trying to dump an api diff.")