diff --git a/aws-api/src/main/scala/net/kemitix/s3thorp/aws/api/S3Client.scala b/aws-api/src/main/scala/net/kemitix/s3thorp/aws/api/S3Client.scala
index ebe2fb1..7835490 100644
--- a/aws-api/src/main/scala/net/kemitix/s3thorp/aws/api/S3Client.scala
+++ b/aws-api/src/main/scala/net/kemitix/s3thorp/aws/api/S3Client.scala
@@ -1,13 +1,13 @@
 package net.kemitix.s3thorp.aws.api
 
 import net.kemitix.s3thorp.aws.api.S3Action.{CopyS3Action, DeleteS3Action}
-import net.kemitix.s3thorp.domain.{Bucket, LocalFile, MD5Hash, RemoteKey, S3ObjectsData}
+import net.kemitix.s3thorp.domain.{Bucket, LocalFile, Logger, MD5Hash, RemoteKey, S3ObjectsData}
 
 trait S3Client[M[_]] {
 
   def listObjects(bucket: Bucket,
                   prefix: RemoteKey
-                 )(implicit info: Int => String => M[Unit]): M[S3ObjectsData]
+                 )(implicit logger: Logger[M]): M[S3ObjectsData]
 
   def upload(localFile: LocalFile,
              bucket: Bucket,
@@ -15,17 +15,16 @@ trait S3Client[M[_]] {
              multiPartThreshold: Long,
              tryCount: Int,
              maxRetries: Int)
-            (implicit info: Int => String => M[Unit],
-             warn: String => M[Unit]): M[S3Action]
+            (implicit logger: Logger[M]): M[S3Action]
 
   def copy(bucket: Bucket,
            sourceKey: RemoteKey,
            hash: MD5Hash,
            targetKey: RemoteKey
-          )(implicit info: Int => String => M[Unit]): M[CopyS3Action]
+          )(implicit logger: Logger[M]): M[CopyS3Action]
 
   def delete(bucket: Bucket,
              remoteKey: RemoteKey
-            )(implicit info: Int => String => M[Unit]): M[DeleteS3Action]
+            )(implicit logger: Logger[M]): M[DeleteS3Action]
 
 }
diff --git a/aws-lib/src/main/scala/net/kemitix/s3thorp/aws/lib/S3ClientCopier.scala b/aws-lib/src/main/scala/net/kemitix/s3thorp/aws/lib/S3ClientCopier.scala
index 1ee9c32..ae7e638 100644
--- a/aws-lib/src/main/scala/net/kemitix/s3thorp/aws/lib/S3ClientCopier.scala
+++ b/aws-lib/src/main/scala/net/kemitix/s3thorp/aws/lib/S3ClientCopier.scala
@@ -6,7 +6,7 @@ import com.amazonaws.services.s3.AmazonS3
 import com.amazonaws.services.s3.model.CopyObjectRequest
 import net.kemitix.s3thorp.aws.api.S3Action.CopyS3Action
 import net.kemitix.s3thorp.aws.lib.S3ClientLogging.{logCopyFinish, logCopyStart}
-import net.kemitix.s3thorp.domain.{Bucket, MD5Hash, RemoteKey}
+import net.kemitix.s3thorp.domain.{Bucket, Logger, MD5Hash, RemoteKey}
 
 class S3ClientCopier[M[_]: Monad](amazonS3: AmazonS3) {
 
@@ -14,7 +14,7 @@ class S3ClientCopier[M[_]: Monad](amazonS3: AmazonS3) {
            sourceKey: RemoteKey,
            hash: MD5Hash,
            targetKey: RemoteKey)
-          (implicit info: Int => String => M[Unit]): M[CopyS3Action] =
+          (implicit logger: Logger[M]): M[CopyS3Action] =
   for {
     _ <- logCopyStart[M](bucket, sourceKey, targetKey)
     _ <- copyObject(bucket, sourceKey, hash, targetKey)
diff --git a/aws-lib/src/main/scala/net/kemitix/s3thorp/aws/lib/S3ClientDeleter.scala b/aws-lib/src/main/scala/net/kemitix/s3thorp/aws/lib/S3ClientDeleter.scala
index 170a049..0cae593 100644
--- a/aws-lib/src/main/scala/net/kemitix/s3thorp/aws/lib/S3ClientDeleter.scala
+++ b/aws-lib/src/main/scala/net/kemitix/s3thorp/aws/lib/S3ClientDeleter.scala
@@ -6,13 +6,13 @@ import com.amazonaws.services.s3.AmazonS3
 import com.amazonaws.services.s3.model.DeleteObjectRequest
 import net.kemitix.s3thorp.aws.api.S3Action.DeleteS3Action
 import net.kemitix.s3thorp.aws.lib.S3ClientLogging.{logDeleteFinish, logDeleteStart}
-import net.kemitix.s3thorp.domain.{Bucket, RemoteKey}
+import net.kemitix.s3thorp.domain.{Bucket, Logger, RemoteKey}
 
 class S3ClientDeleter[M[_]: Monad](amazonS3: AmazonS3) {
 
   def delete(bucket: Bucket,
              remoteKey: RemoteKey)
-            (implicit info: Int => String => M[Unit]): M[DeleteS3Action] =
+            (implicit logger: Logger[M]): M[DeleteS3Action] =
     for {
       _ <- logDeleteStart[M](bucket, remoteKey)
       _ <- deleteObject(bucket, remoteKey)
diff --git a/aws-lib/src/main/scala/net/kemitix/s3thorp/aws/lib/S3ClientLogging.scala b/aws-lib/src/main/scala/net/kemitix/s3thorp/aws/lib/S3ClientLogging.scala
index 4e9669d..c56cdba 100644
--- a/aws-lib/src/main/scala/net/kemitix/s3thorp/aws/lib/S3ClientLogging.scala
+++ b/aws-lib/src/main/scala/net/kemitix/s3thorp/aws/lib/S3ClientLogging.scala
@@ -2,45 +2,40 @@ package net.kemitix.s3thorp.aws.lib
 
 import cats.Monad
 import com.amazonaws.services.s3.model.PutObjectResult
-import net.kemitix.s3thorp.domain.{Bucket, LocalFile, RemoteKey}
+import net.kemitix.s3thorp.domain.{Bucket, LocalFile, Logger, RemoteKey}
 
 object S3ClientLogging {
 
   def logListObjectsStart[M[_]: Monad](bucket: Bucket,
                           prefix: RemoteKey)
-                         (implicit info: Int => String => M[Unit]): M[Unit] =
-    info(1)(s"Fetch S3 Summary: ${bucket.name}:${prefix.key}")
+                         (implicit logger: Logger[M]): M[Unit] =
+    logger.info(s"Fetch S3 Summary: ${bucket.name}:${prefix.key}")
 
   def logListObjectsFinish[M[_]: Monad](bucket: Bucket,
                            prefix: RemoteKey)
-                          (implicit info: Int => String => M[Unit]): M[Unit] =
-    info(2)(s"Fetched S3 Summary: ${bucket.name}:${prefix.key}")
-
-  def logUploadFinish[M[_]: Monad](localFile: LocalFile,
-                      bucket: Bucket)
-                     (implicit info: Int => String => M[Unit]): PutObjectResult => M[Unit] =
-    _ => info(2)(s"Uploaded: ${bucket.name}:${localFile.remoteKey.key}")
+                          (implicit logger: Logger[M]): M[Unit] =
+    logger.info(s"Fetched S3 Summary: ${bucket.name}:${prefix.key}")
 
   def logCopyStart[M[_]: Monad](bucket: Bucket,
                                 sourceKey: RemoteKey,
                                 targetKey: RemoteKey)
-                               (implicit info: Int => String => M[Unit]): M[Unit] =
-    info(1)(s"Copy: ${bucket.name}:${sourceKey.key} => ${targetKey.key}")
+                               (implicit logger: Logger[M]): M[Unit] =
+    logger.info(s"Copy: ${bucket.name}:${sourceKey.key} => ${targetKey.key}")
 
   def logCopyFinish[M[_]: Monad](bucket: Bucket,
                     sourceKey: RemoteKey,
                     targetKey: RemoteKey)
-                   (implicit info: Int => String => M[Unit]): M[Unit] =
-    info(2)(s"Copied: ${bucket.name}:${sourceKey.key} => ${targetKey.key}")
+                   (implicit logger: Logger[M]): M[Unit] =
+    logger.info(s"Copied: ${bucket.name}:${sourceKey.key} => ${targetKey.key}")
 
   def logDeleteStart[M[_]: Monad](bucket: Bucket,
                      remoteKey: RemoteKey)
-                    (implicit info: Int => String => M[Unit]): M[Unit] =
-      info(1)(s"Delete: ${bucket.name}:${remoteKey.key}")
+                    (implicit logger: Logger[M]): M[Unit] =
+      logger.info(s"Delete: ${bucket.name}:${remoteKey.key}")
 
   def logDeleteFinish[M[_]: Monad](bucket: Bucket,
                       remoteKey: RemoteKey)
-                     (implicit info: Int => String => M[Unit]): M[Unit] =
-      info(2)(s"Deleted: ${bucket.name}:${remoteKey.key}")
+                     (implicit logger: Logger[M]): M[Unit] =
+      logger.info(s"Deleted: ${bucket.name}:${remoteKey.key}")
 
 }
diff --git a/aws-lib/src/main/scala/net/kemitix/s3thorp/aws/lib/S3ClientObjectLister.scala b/aws-lib/src/main/scala/net/kemitix/s3thorp/aws/lib/S3ClientObjectLister.scala
index dd5898c..272d90d 100644
--- a/aws-lib/src/main/scala/net/kemitix/s3thorp/aws/lib/S3ClientObjectLister.scala
+++ b/aws-lib/src/main/scala/net/kemitix/s3thorp/aws/lib/S3ClientObjectLister.scala
@@ -15,7 +15,7 @@ class S3ClientObjectLister[M[_]: Monad](amazonS3: AmazonS3) {
 
   def listObjects(bucket: Bucket,
                   prefix: RemoteKey)
-                 (implicit info: Int => String => M[Unit]): M[S3ObjectsData] = {
+                 (implicit logger: Logger[M]): M[S3ObjectsData] = {
 
     type Token = String
     type Batch = (Stream[S3ObjectSummary], Option[Token])
diff --git a/aws-lib/src/main/scala/net/kemitix/s3thorp/aws/lib/ThorpS3Client.scala b/aws-lib/src/main/scala/net/kemitix/s3thorp/aws/lib/ThorpS3Client.scala
index b821c34..cfa5456 100644
--- a/aws-lib/src/main/scala/net/kemitix/s3thorp/aws/lib/ThorpS3Client.scala
+++ b/aws-lib/src/main/scala/net/kemitix/s3thorp/aws/lib/ThorpS3Client.scala
@@ -18,14 +18,14 @@ class ThorpS3Client[M[_]: Monad](amazonS3Client: => AmazonS3,
 
   override def listObjects(bucket: Bucket,
                            prefix: RemoteKey)
-                          (implicit info: Int => String => M[Unit]): M[S3ObjectsData] =
+                          (implicit logger: Logger[M]): M[S3ObjectsData] =
     objectLister.listObjects(bucket, prefix)
 
   override def copy(bucket: Bucket,
                     sourceKey: RemoteKey,
                     hash: MD5Hash,
                     targetKey: RemoteKey)
-                   (implicit info: Int => String => M[Unit]): M[CopyS3Action] =
+                   (implicit logger: Logger[M]): M[CopyS3Action] =
     copier.copy(bucket, sourceKey,hash, targetKey)
 
   override def upload(localFile: LocalFile,
@@ -34,13 +34,12 @@ class ThorpS3Client[M[_]: Monad](amazonS3Client: => AmazonS3,
                       multiPartThreshold: Long,
                       tryCount: Int,
                       maxRetries: Int)
-                     (implicit info: Int => String => M[Unit],
-                      warn: String => M[Unit]): M[S3Action] =
+                     (implicit logger: Logger[M]): M[S3Action] =
     uploader.upload(localFile, bucket, progressListener, multiPartThreshold, 1, maxRetries)
 
   override def delete(bucket: Bucket,
                       remoteKey: RemoteKey)
-                     (implicit info: Int => String => M[Unit]): M[DeleteS3Action] =
+                     (implicit logger: Logger[M]): M[DeleteS3Action] =
     deleter.delete(bucket, remoteKey)
 
 }
diff --git a/aws-lib/src/main/scala/net/kemitix/s3thorp/aws/lib/Uploader.scala b/aws-lib/src/main/scala/net/kemitix/s3thorp/aws/lib/Uploader.scala
index 3576bfa..98b928e 100644
--- a/aws-lib/src/main/scala/net/kemitix/s3thorp/aws/lib/Uploader.scala
+++ b/aws-lib/src/main/scala/net/kemitix/s3thorp/aws/lib/Uploader.scala
@@ -10,7 +10,7 @@ import net.kemitix.s3thorp.aws.api.S3Action.{ErroredS3Action, UploadS3Action}
 import net.kemitix.s3thorp.aws.api.UploadEvent.{ByteTransferEvent, RequestEvent, TransferEvent}
 import net.kemitix.s3thorp.aws.api.{S3Action, UploadProgressListener}
 import net.kemitix.s3thorp.aws.lib.UploaderLogging.{logMultiPartUploadFinished, logMultiPartUploadStart}
-import net.kemitix.s3thorp.domain.{Bucket, LocalFile, MD5Hash, RemoteKey}
+import net.kemitix.s3thorp.domain.{Bucket, LocalFile, Logger, MD5Hash, RemoteKey}
 
 import scala.util.Try
 
@@ -26,8 +26,7 @@ class Uploader[M[_]: Monad](transferManager: => AmazonTransferManager) {
              multiPartThreshold: Long,
              tryCount: Int,
              maxRetries: Int)
-            (implicit info: Int => String => M[Unit],
-             warn: String => M[Unit]): M[S3Action] =
+            (implicit logger: Logger[M]): M[S3Action] =
     for {
       _ <- logMultiPartUploadStart[M](localFile, tryCount)
       upload <- transfer(localFile, bucket, uploadProgressListener)
diff --git a/aws-lib/src/main/scala/net/kemitix/s3thorp/aws/lib/UploaderLogging.scala b/aws-lib/src/main/scala/net/kemitix/s3thorp/aws/lib/UploaderLogging.scala
index 207c111..ab3d8b1 100644
--- a/aws-lib/src/main/scala/net/kemitix/s3thorp/aws/lib/UploaderLogging.scala
+++ b/aws-lib/src/main/scala/net/kemitix/s3thorp/aws/lib/UploaderLogging.scala
@@ -3,20 +3,20 @@ package net.kemitix.s3thorp.aws.lib
 import cats.Monad
 import net.kemitix.s3thorp.domain.Terminal.clearLine
 import net.kemitix.s3thorp.domain.SizeTranslation.sizeInEnglish
-import net.kemitix.s3thorp.domain.LocalFile
+import net.kemitix.s3thorp.domain.{LocalFile, Logger}
 
 object UploaderLogging {
 
   def logMultiPartUploadStart[M[_]: Monad](localFile: LocalFile,
                               tryCount: Int)
-                             (implicit info: Int => String => M[Unit]): M[Unit] = {
+                             (implicit logger: Logger[M]): M[Unit] = {
       val tryMessage = if (tryCount == 1) "" else s"try $tryCount"
       val size = sizeInEnglish(localFile.file.length)
-      info(1)(s"${clearLine}upload:$tryMessage:$size:${localFile.remoteKey.key}")
+      logger.info(s"${clearLine}upload:$tryMessage:$size:${localFile.remoteKey.key}")
     }
 
   def logMultiPartUploadFinished[M[_]: Monad](localFile: LocalFile)
-                                (implicit info: Int => String => M[Unit]): M[Unit] =
-    info(4)(s"upload:finished: ${localFile.remoteKey.key}")
+                                (implicit logger: Logger[M]): M[Unit] =
+    logger.debug(s"upload:finished: ${localFile.remoteKey.key}")
 
 }
diff --git a/aws-lib/src/test/scala/net/kemitix/s3thorp/aws/lib/DummyLogger.scala b/aws-lib/src/test/scala/net/kemitix/s3thorp/aws/lib/DummyLogger.scala
new file mode 100644
index 0000000..ff4cf04
--- /dev/null
+++ b/aws-lib/src/test/scala/net/kemitix/s3thorp/aws/lib/DummyLogger.scala
@@ -0,0 +1,16 @@
+package net.kemitix.s3thorp.aws.lib
+
+import cats.Monad
+import net.kemitix.s3thorp.domain.Logger
+
+class DummyLogger[M[_]: Monad] extends Logger[M] {
+
+  override def debug(message: => String): M[Unit] = Monad[M].unit
+
+  override def info(message: =>String): M[Unit] = Monad[M].unit
+
+  override def warn(message: String): M[Unit] = Monad[M].unit
+
+  override def error(message: String): M[Unit] = Monad[M].unit
+
+}
diff --git a/aws-lib/src/test/scala/net/kemitix/s3thorp/aws/lib/S3ClientSuite.scala b/aws-lib/src/test/scala/net/kemitix/s3thorp/aws/lib/S3ClientSuite.scala
index c4a0690..f2c8821 100644
--- a/aws-lib/src/test/scala/net/kemitix/s3thorp/aws/lib/S3ClientSuite.scala
+++ b/aws-lib/src/test/scala/net/kemitix/s3thorp/aws/lib/S3ClientSuite.scala
@@ -23,8 +23,7 @@ class S3ClientSuite
 
   private val prefix = RemoteKey("prefix")
   implicit private val config: Config = Config(Bucket("bucket"), prefix, source = source)
-  implicit private val logInfo: Int => String => Id[Unit] = _ => _ => ()
-  implicit private val logWarn: String => Id[Unit] = _ => ()
+  implicit private val implLogger: Logger[Id] = new DummyLogger[Id]
   private val fileToKey = KeyGenerator.generateKey(config.source, config.prefix) _
 
   describe("getS3Status") {
diff --git a/aws-lib/src/test/scala/net/kemitix/s3thorp/aws/lib/ThorpS3ClientSuite.scala b/aws-lib/src/test/scala/net/kemitix/s3thorp/aws/lib/ThorpS3ClientSuite.scala
index 86bc114..03bd7d7 100644
--- a/aws-lib/src/test/scala/net/kemitix/s3thorp/aws/lib/ThorpS3ClientSuite.scala
+++ b/aws-lib/src/test/scala/net/kemitix/s3thorp/aws/lib/ThorpS3ClientSuite.scala
@@ -21,7 +21,7 @@ class ThorpS3ClientSuite
     val source = Resource(this, "upload")
     val prefix = RemoteKey("prefix")
     implicit val config: Config = Config(Bucket("bucket"), prefix, source = source)
-    implicit val logInfo: Int => String => Id[Unit] = _ => _ => ()
+    implicit val implLogger: Logger[Id] = new DummyLogger[Id]
 
     val lm = LastModified(Instant.now.truncatedTo(ChronoUnit.MILLIS))
 
diff --git a/aws-lib/src/test/scala/net/kemitix/s3thorp/aws/lib/UploaderSuite.scala b/aws-lib/src/test/scala/net/kemitix/s3thorp/aws/lib/UploaderSuite.scala
index 0e681cb..d2d5cde 100644
--- a/aws-lib/src/test/scala/net/kemitix/s3thorp/aws/lib/UploaderSuite.scala
+++ b/aws-lib/src/test/scala/net/kemitix/s3thorp/aws/lib/UploaderSuite.scala
@@ -20,8 +20,7 @@ class UploaderSuite
   private val source = Resource(this, ".")
   private val prefix = RemoteKey("prefix")
   implicit private val config: Config = Config(Bucket("bucket"), prefix, source = source)
-  implicit private val logInfo: Int => String => Id[Unit] = _ => _ => ()
-  implicit private val logWarn: String => Id[Unit] = _ => ()
+  implicit private val implLogger: Logger[Id] = new DummyLogger[Id]
   private val fileToKey = generateKey(config.source, config.prefix) _
   val lastModified = LastModified(Instant.now())
 
diff --git a/cli/src/main/scala/net/kemitix/s3thorp/cli/Logger.scala b/cli/src/main/scala/net/kemitix/s3thorp/cli/Logger.scala
deleted file mode 100644
index 6f8fb89..0000000
--- a/cli/src/main/scala/net/kemitix/s3thorp/cli/Logger.scala
+++ /dev/null
@@ -1,16 +0,0 @@
-package net.kemitix.s3thorp.cli
-
-import cats.Monad
-
-
-class Logger[M[_]: Monad](verbosity: Int)  {
-
-  def info(level: Int)(message: String): M[Unit] =
-    if (verbosity >= level) Monad[M].pure(println(s"[INFO:$level] $message"))
-    else Monad[M].unit
-
-  def warn(message: String): M[Unit] = Monad[M].pure(println(s"[  WARN] $message"))
-
-  def error(message: String): M[Unit] = Monad[M].pure(println(s"[ ERROR] $message"))
-
-}
diff --git a/cli/src/main/scala/net/kemitix/s3thorp/cli/Main.scala b/cli/src/main/scala/net/kemitix/s3thorp/cli/Main.scala
index 90b5349..bfa42fd 100644
--- a/cli/src/main/scala/net/kemitix/s3thorp/cli/Main.scala
+++ b/cli/src/main/scala/net/kemitix/s3thorp/cli/Main.scala
@@ -12,14 +12,14 @@ object Main extends IOApp {
     Config(source = Paths.get(".").toFile)
 
   override def run(args: List[String]): IO[ExitCode] = {
-    val logger = new Logger[IO](1)
+    val logger = new PrintLogger[IO](1)
     ParseArgs(args, defaultConfig)
       .map(Program[IO])
       .getOrElse(IO(ExitCode.Error))
       .guaranteeCase {
           case Canceled => logger.warn("Interrupted")
           case Error(e) => logger.error(e.getMessage)
-          case Completed => logger.info(1)("Done")
+          case Completed => logger.info("Done")
       }
   }
 
diff --git a/cli/src/main/scala/net/kemitix/s3thorp/cli/PrintLogger.scala b/cli/src/main/scala/net/kemitix/s3thorp/cli/PrintLogger.scala
new file mode 100644
index 0000000..53ad895
--- /dev/null
+++ b/cli/src/main/scala/net/kemitix/s3thorp/cli/PrintLogger.scala
@@ -0,0 +1,16 @@
+package net.kemitix.s3thorp.cli
+
+import cats.Monad
+import net.kemitix.s3thorp.domain.Logger
+
+class PrintLogger[M[_]: Monad](verbosity: Int) extends Logger[M] {
+
+  override def debug(message: => String): M[Unit] = Monad[M].pure(println(s"[ DEBUG] $message"))
+
+  override def info(message: => String): M[Unit] = Monad[M].pure(println(s"[  INFO] $message"))
+
+  override def warn(message: String): M[Unit] = Monad[M].pure(println(s"[  WARN] $message"))
+
+  override def error(message: String): M[Unit] = Monad[M].pure(println(s"[ ERROR] $message"))
+
+}
diff --git a/cli/src/main/scala/net/kemitix/s3thorp/cli/Program.scala b/cli/src/main/scala/net/kemitix/s3thorp/cli/Program.scala
index c6318a5..0f222da 100644
--- a/cli/src/main/scala/net/kemitix/s3thorp/cli/Program.scala
+++ b/cli/src/main/scala/net/kemitix/s3thorp/cli/Program.scala
@@ -3,27 +3,25 @@ package net.kemitix.s3thorp.cli
 import java.io.File
 
 import cats.Monad
-import cats.implicits._
 import cats.effect.ExitCode
+import cats.implicits._
 import net.kemitix.s3thorp.aws.lib.S3ClientBuilder
 import net.kemitix.s3thorp.core.MD5HashGenerator.md5File
-import net.kemitix.s3thorp.core.{MD5HashGenerator, Sync}
-import net.kemitix.s3thorp.domain.Config
+import net.kemitix.s3thorp.core.Sync
+import net.kemitix.s3thorp.domain.{Config, Logger}
 
 object Program {
 
   def apply[M[_]: Monad](config: Config): M[ExitCode] = {
-    val logger = new Logger[M](config.verbose)
-    val info = (l: Int) => (m: String) => logger.info(l) (m)
-    val warn = (w: String) => logger.warn(w)
+    val logger = new PrintLogger[M](config.verbose)
     for {
-      _ <- info(1)("S3Thorp - hashed sync for s3")
-      _ <- Sync.run[M](config, S3ClientBuilder.defaultClient, hashGenerator(info), info, warn)
+      _ <- logger.info("S3Thorp - hashed sync for s3")
+      _ <- Sync.run[M](config, S3ClientBuilder.defaultClient, hashGenerator(logger), logger)
     } yield ExitCode.Success
   }
 
-  private def hashGenerator[M[_]: Monad](info: Int => String => M[Unit]) = {
-    implicit val logInfo: Int => String => M[Unit] = info
+  private def hashGenerator[M[_]: Monad](logger: Logger[M]) = {
+    implicit val impLogger: Logger[M] = logger
     file: File => md5File[M](file)
   }
 
diff --git a/core/src/main/scala/net.kemitix.s3thorp.core/ActionSubmitter.scala b/core/src/main/scala/net.kemitix.s3thorp.core/ActionSubmitter.scala
index b15ee6b..2e05f83 100644
--- a/core/src/main/scala/net.kemitix.s3thorp.core/ActionSubmitter.scala
+++ b/core/src/main/scala/net.kemitix.s3thorp.core/ActionSubmitter.scala
@@ -5,30 +5,29 @@ import cats.implicits._
 import net.kemitix.s3thorp.aws.api.S3Action.DoNothingS3Action
 import net.kemitix.s3thorp.aws.api.{S3Action, S3Client, UploadProgressListener}
 import net.kemitix.s3thorp.core.Action.{DoNothing, ToCopy, ToDelete, ToUpload}
-import net.kemitix.s3thorp.domain.Config
+import net.kemitix.s3thorp.domain.{Config, Logger}
 
 object ActionSubmitter {
 
   def submitAction[M[_]: Monad](s3Client: S3Client[M], action: Action)
                                (implicit c: Config,
-                                info: Int => String => M[Unit],
-                                warn: String => M[Unit]): Stream[M[S3Action]] = {
+                                logger: Logger[M]): Stream[M[S3Action]] = {
     Stream(
       action match {
         case ToUpload(bucket, localFile) =>
           for {
-            _ <- info(4) (s"    Upload: ${localFile.relative}")
+            _ <- logger.info(s"    Upload: ${localFile.relative}")
             progressListener = new UploadProgressListener(localFile)
             action <- s3Client.upload(localFile, bucket, progressListener, c.multiPartThreshold, 1, c.maxRetries)
           } yield action
         case ToCopy(bucket, sourceKey, hash, targetKey) =>
           for {
-            _ <- info(4)(s"      Copy: ${sourceKey.key} => ${targetKey.key}")
+            _ <- logger.info(s"      Copy: ${sourceKey.key} => ${targetKey.key}")
             action <- s3Client.copy(bucket, sourceKey, hash, targetKey)
           } yield action
         case ToDelete(bucket, remoteKey) =>
           for {
-            _ <- info(4)(s"    Delete: ${remoteKey.key}")
+            _ <- logger.info(s"    Delete: ${remoteKey.key}")
             action <- s3Client.delete(bucket, remoteKey)
           } yield action
         case DoNothing(bucket, remoteKey) =>
diff --git a/core/src/main/scala/net.kemitix.s3thorp.core/LocalFileStream.scala b/core/src/main/scala/net.kemitix.s3thorp.core/LocalFileStream.scala
index 10f9f5f..8694536 100644
--- a/core/src/main/scala/net.kemitix.s3thorp.core/LocalFileStream.scala
+++ b/core/src/main/scala/net.kemitix.s3thorp.core/LocalFileStream.scala
@@ -6,14 +6,14 @@ import java.nio.file.Path
 import cats.Monad
 import cats.implicits._
 import net.kemitix.s3thorp.core.KeyGenerator.generateKey
-import net.kemitix.s3thorp.domain.{Config, Filter, LocalFile, MD5Hash}
+import net.kemitix.s3thorp.domain.{Config, Filter, LocalFile, Logger, MD5Hash}
 
 object LocalFileStream {
 
   def findFiles[M[_]: Monad](file: File,
-                md5HashGenerator: File => M[MD5Hash],
-                info: Int => String => M[Unit])
-               (implicit c: Config): M[Stream[LocalFile]] = {
+                             md5HashGenerator: File => M[MD5Hash])
+                            (implicit c: Config,
+                             logger: Logger[M]): M[Stream[LocalFile]] = {
 
     val filters: Path => Boolean = Filter.isIncluded(c.filters)
 
@@ -41,10 +41,10 @@ object LocalFileStream {
             .flatMap(lfs => acc.map(s => s ++ lfs)))
 
       for {
-        _ <- info(2)(s"- Entering: $file")
+        _ <- logger.info(s"- Entering: $file")
         fs <- dirPaths(file)
         lfs <- recurse(fs)
-        _ <- info(5)(s"- Leaving : $file")
+        _ <- logger.debug(s"- Leaving : $file")
       } yield lfs
     }
 
diff --git a/core/src/main/scala/net.kemitix.s3thorp.core/MD5HashGenerator.scala b/core/src/main/scala/net.kemitix.s3thorp.core/MD5HashGenerator.scala
index 85f8ee3..95ac20b 100644
--- a/core/src/main/scala/net.kemitix.s3thorp.core/MD5HashGenerator.scala
+++ b/core/src/main/scala/net.kemitix.s3thorp.core/MD5HashGenerator.scala
@@ -5,14 +5,14 @@ import java.security.MessageDigest
 
 import cats.Monad
 import cats.implicits._
-import net.kemitix.s3thorp.domain.MD5Hash
+import net.kemitix.s3thorp.domain.{Logger, MD5Hash}
 
 import scala.collection.immutable.NumericRange
 
 object MD5HashGenerator {
 
   def md5File[M[_]: Monad](file: File)
-                          (implicit info: Int => String => M[Unit]): M[MD5Hash] = {
+                          (implicit logger: Logger[M]): M[MD5Hash] = {
 
     val maxBufferSize = 8048
     val defaultBuffer = new Array[Byte](maxBufferSize)
@@ -54,10 +54,10 @@ object MD5HashGenerator {
       } yield md5
 
     for {
-      _ <- info(5)(s"md5:reading:size ${file.length}:$file")
+      _ <- logger.debug(s"md5:reading:size ${file.length}:$file")
       md5 <- readFile
       hash = MD5Hash(md5)
-      _ <- info(4)(s"md5:generated:${hash.hash}:$file")
+      _ <- logger.debug(s"md5:generated:${hash.hash}:$file")
     } yield hash
   }
 
diff --git a/core/src/main/scala/net.kemitix.s3thorp.core/Sync.scala b/core/src/main/scala/net.kemitix.s3thorp.core/Sync.scala
index 0269b47..f509563 100644
--- a/core/src/main/scala/net.kemitix.s3thorp.core/Sync.scala
+++ b/core/src/main/scala/net.kemitix.s3thorp.core/Sync.scala
@@ -11,19 +11,17 @@ import net.kemitix.s3thorp.core.ActionSubmitter.submitAction
 import net.kemitix.s3thorp.core.LocalFileStream.findFiles
 import net.kemitix.s3thorp.core.S3MetaDataEnricher.getMetadata
 import net.kemitix.s3thorp.core.SyncLogging.{logFileScan, logRunFinished, logRunStart}
-import net.kemitix.s3thorp.domain.{Config, LocalFile, MD5Hash, S3MetaData, S3ObjectsData}
+import net.kemitix.s3thorp.domain.{Config, LocalFile, Logger, MD5Hash, S3MetaData, S3ObjectsData}
 
 object Sync {
 
   def run[M[_]: Monad](config: Config,
                        s3Client: S3Client[M],
                        md5HashGenerator: File => M[MD5Hash],
-                       info: Int => String => M[Unit],
-                       warn: String => M[Unit]): M[Unit] = {
+                       logger: Logger[M]): M[Unit] = {
 
     implicit val c: Config = config
-    implicit val logInfo: Int => String => M[Unit] = info
-    implicit val logWarn: String => M[Unit] = warn
+    implicit val implLogger: Logger[M] = logger
 
     def metaData(s3Data: S3ObjectsData, sFiles: Stream[LocalFile]) =
       Monad[M].pure(sFiles.map(file => getMetadata(file, s3Data)))
@@ -36,7 +34,7 @@ object Sync {
 
     def copyUploadActions(s3Data: S3ObjectsData): M[Stream[S3Action]] =
       (for {
-        files <- findFiles(c.source, md5HashGenerator, info)
+        files <- findFiles(c.source, md5HashGenerator)
         metaData <- metaData(s3Data, files)
         actions <- actions(metaData)
         s3Actions <- submit(actions)
@@ -54,12 +52,12 @@ object Sync {
         .sequence
 
     for {
-      _ <- logRunStart(info)
-      s3data <- s3Client.listObjects(c.bucket, c.prefix)(info)
-      _ <- logFileScan(info)
+      _ <- logRunStart[M]
+      s3data <- s3Client.listObjects(c.bucket, c.prefix)
+      _ <- logFileScan[M]
       copyUploadActions <- copyUploadActions(s3data)
       deleteActions <- deleteActions(s3data)
-      _ <- logRunFinished(copyUploadActions ++ deleteActions, info)
+      _ <- logRunFinished[M](copyUploadActions ++ deleteActions)
     } yield ()
   }
 
diff --git a/core/src/main/scala/net.kemitix.s3thorp.core/SyncLogging.scala b/core/src/main/scala/net.kemitix.s3thorp.core/SyncLogging.scala
index 806ac16..e121b2b 100644
--- a/core/src/main/scala/net.kemitix.s3thorp.core/SyncLogging.scala
+++ b/core/src/main/scala/net.kemitix.s3thorp.core/SyncLogging.scala
@@ -4,28 +4,28 @@ import cats.Monad
 import cats.implicits._
 import net.kemitix.s3thorp.aws.api.S3Action
 import net.kemitix.s3thorp.aws.api.S3Action.{CopyS3Action, DeleteS3Action, ErroredS3Action, UploadS3Action}
-import net.kemitix.s3thorp.domain.Config
+import net.kemitix.s3thorp.domain.{Config, Logger}
 
 // Logging for the Sync class
 object SyncLogging {
 
-  def logRunStart[M[_]: Monad](info: Int => String => M[Unit])
-                       (implicit c: Config): M[Unit] =
-    info(1)(s"Bucket: ${c.bucket.name}, Prefix: ${c.prefix.key}, Source: ${c.source}, ")
+  def logRunStart[M[_]: Monad](implicit c: Config,
+                               logger: Logger[M]): M[Unit] =
+    logger.info(s"Bucket: ${c.bucket.name}, Prefix: ${c.prefix.key}, Source: ${c.source}, ")
 
-  def logFileScan[M[_]: Monad](info: Int => String => M[Unit])
-                 (implicit c: Config): M[Unit] =
-    info(1)(s"Scanning local files: ${c.source}...")
+  def logFileScan[M[_]: Monad](implicit c: Config,
+                               logger: Logger[M]): M[Unit] =
+    logger.info(s"Scanning local files: ${c.source}...")
 
-  def logRunFinished[M[_]: Monad](actions: Stream[S3Action],
-                     info: Int => String => M[Unit])
-                    (implicit c: Config): M[Unit] = {
+  def logRunFinished[M[_]: Monad](actions: Stream[S3Action])
+                                 (implicit c: Config,
+                                  logger: Logger[M]): M[Unit] = {
     val counters = actions.foldLeft(Counters())(countActivities)
     for {
-      _ <- info(1)(s"Uploaded ${counters.uploaded} files")
-      _ <- info(1)(s"Copied   ${counters.copied} files")
-      _ <- info(1)(s"Deleted  ${counters.deleted} files")
-      _ <- info(1)(s"Errors   ${counters.errors}")
+      _ <- logger.info(s"Uploaded ${counters.uploaded} files")
+      _ <- logger.info(s"Copied   ${counters.copied} files")
+      _ <- logger.info(s"Deleted  ${counters.deleted} files")
+      _ <- logger.info(s"Errors   ${counters.errors}")
     } yield ()
   }
 
diff --git a/core/src/test/scala/net/kemitix/s3thorp/core/ActionGeneratorSuite.scala b/core/src/test/scala/net/kemitix/s3thorp/core/ActionGeneratorSuite.scala
index 913bd0c..3e6ebc7 100644
--- a/core/src/test/scala/net/kemitix/s3thorp/core/ActionGeneratorSuite.scala
+++ b/core/src/test/scala/net/kemitix/s3thorp/core/ActionGeneratorSuite.scala
@@ -13,7 +13,6 @@ class ActionGeneratorSuite
   private val prefix = RemoteKey("prefix")
   private val bucket = Bucket("bucket")
   implicit private val config: Config = Config(bucket, prefix, source = source)
-  implicit private val logInfo: Int => String => Unit = l => i => ()
   private val fileToKey = KeyGenerator.generateKey(config.source, config.prefix) _
   val lastModified = LastModified(Instant.now())
 
diff --git a/core/src/test/scala/net/kemitix/s3thorp/core/DummyLogger.scala b/core/src/test/scala/net/kemitix/s3thorp/core/DummyLogger.scala
new file mode 100644
index 0000000..b7191c5
--- /dev/null
+++ b/core/src/test/scala/net/kemitix/s3thorp/core/DummyLogger.scala
@@ -0,0 +1,16 @@
+package net.kemitix.s3thorp.core
+
+import cats.Monad
+import net.kemitix.s3thorp.domain.Logger
+
+class DummyLogger[M[_]: Monad] extends Logger[M] {
+
+  override def debug(message: => String): M[Unit] = Monad[M].unit
+
+  override def info(message: =>String): M[Unit] = Monad[M].unit
+
+  override def warn(message: String): M[Unit] = Monad[M].unit
+
+  override def error(message: String): M[Unit] = Monad[M].unit
+
+}
diff --git a/core/src/test/scala/net/kemitix/s3thorp/core/LocalFileStreamSuite.scala b/core/src/test/scala/net/kemitix/s3thorp/core/LocalFileStreamSuite.scala
index 95ec9be..af95145 100644
--- a/core/src/test/scala/net/kemitix/s3thorp/core/LocalFileStreamSuite.scala
+++ b/core/src/test/scala/net/kemitix/s3thorp/core/LocalFileStreamSuite.scala
@@ -3,20 +3,20 @@ package net.kemitix.s3thorp.core
 import java.io.File
 
 import cats.Id
-import net.kemitix.s3thorp.domain.{Config, LocalFile, MD5Hash}
+import net.kemitix.s3thorp.domain.{Config, LocalFile, Logger, MD5Hash}
 import org.scalatest.FunSpec
 
 class LocalFileStreamSuite extends FunSpec {
 
   val uploadResource = Resource(this, "upload")
   implicit val config: Config = Config(source = uploadResource)
-  implicit private val logInfo: Int => String => Id[Unit] = l => i => ()
+  implicit private val logger: Logger[Id] = new DummyLogger[Id]
   val md5HashGenerator: File => Id[MD5Hash] = file => MD5HashGenerator.md5File[Id](file)
 
   describe("findFiles") {
     it("should find all files") {
       val result: Set[String] =
-        LocalFileStream.findFiles[Id](uploadResource, md5HashGenerator, logInfo).toSet
+        LocalFileStream.findFiles[Id](uploadResource, md5HashGenerator).toSet
           .map { x: LocalFile => x.relative.toString }
       assertResult(Set("subdir/leaf-file", "root-file"))(result)
     }
diff --git a/core/src/test/scala/net/kemitix/s3thorp/core/MD5HashGeneratorTest.scala b/core/src/test/scala/net/kemitix/s3thorp/core/MD5HashGeneratorTest.scala
index 674fa22..a71b57a 100644
--- a/core/src/test/scala/net/kemitix/s3thorp/core/MD5HashGeneratorTest.scala
+++ b/core/src/test/scala/net/kemitix/s3thorp/core/MD5HashGeneratorTest.scala
@@ -2,7 +2,7 @@ package net.kemitix.s3thorp.core
 
 import cats.Id
 import net.kemitix.s3thorp.core.MD5HashData.rootHash
-import net.kemitix.s3thorp.domain.{Bucket, Config, MD5Hash, RemoteKey}
+import net.kemitix.s3thorp.domain.{Bucket, Config, Logger, MD5Hash, RemoteKey}
 import org.scalatest.FunSpec
 
 class MD5HashGeneratorTest extends FunSpec {
@@ -10,7 +10,7 @@ class MD5HashGeneratorTest extends FunSpec {
   private val source = Resource(this, "upload")
   private val prefix = RemoteKey("prefix")
   implicit private val config: Config = Config(Bucket("bucket"), prefix, source = source)
-  implicit private val logInfo: Int => String => Id[Unit] = l => i => ()
+  implicit private val logger: Logger[Id] = new DummyLogger[Id]
 
     describe("read a small file (smaller than buffer)") {
       val file = Resource(this, "upload/root-file")
diff --git a/core/src/test/scala/net/kemitix/s3thorp/core/S3MetaDataEnricherSuite.scala b/core/src/test/scala/net/kemitix/s3thorp/core/S3MetaDataEnricherSuite.scala
index 5b110cd..8ed0610 100644
--- a/core/src/test/scala/net/kemitix/s3thorp/core/S3MetaDataEnricherSuite.scala
+++ b/core/src/test/scala/net/kemitix/s3thorp/core/S3MetaDataEnricherSuite.scala
@@ -12,7 +12,6 @@ class S3MetaDataEnricherSuite
   private val source = Resource(this, "upload")
   private val prefix = RemoteKey("prefix")
   implicit private val config: Config = Config(Bucket("bucket"), prefix, source = source)
-  implicit private val logInfo: Int => String => Unit = l => i => ()
   private val fileToKey = KeyGenerator.generateKey(config.source, config.prefix) _
   val lastModified = LastModified(Instant.now())
 
diff --git a/core/src/test/scala/net/kemitix/s3thorp/core/SyncSuite.scala b/core/src/test/scala/net/kemitix/s3thorp/core/SyncSuite.scala
index d310393..2db8659 100644
--- a/core/src/test/scala/net/kemitix/s3thorp/core/SyncSuite.scala
+++ b/core/src/test/scala/net/kemitix/s3thorp/core/SyncSuite.scala
@@ -17,8 +17,7 @@ class SyncSuite
   private val source = Resource(this, "upload")
   private val prefix = RemoteKey("prefix")
   val config = Config(Bucket("bucket"), prefix, source = source)
-  implicit private val logInfo: Int => String => Id[Unit] = _ => _ => ()
-  implicit private val logWarn: String => Id[Unit] = _ => ()
+  implicit private val logger: Logger[Id] = new DummyLogger[Id]
   private val lastModified = LastModified(Instant.now)
   private val fileToKey: File => RemoteKey = KeyGenerator.generateKey(source, prefix)
   private val rootFile = LocalFile.resolve("root-file", rootHash, source, fileToKey)
@@ -38,7 +37,7 @@ class SyncSuite
       val s3Client = new RecordingClient(testBucket, S3ObjectsData(
         byHash = Map(),
         byKey = Map()))
-      Sync.run(config, s3Client, md5HashGenerator, logInfo, logWarn)
+      Sync.run(config, s3Client, md5HashGenerator, logger)
       it("uploads all files") {
         val expectedUploads = Map(
           "subdir/leaf-file" -> leafRemoteKey,
@@ -64,7 +63,7 @@ class SyncSuite
           RemoteKey("prefix/root-file") -> HashModified(rootHash, lastModified),
           RemoteKey("prefix/subdir/leaf-file") -> HashModified(leafHash, lastModified)))
       val s3Client = new RecordingClient(testBucket, s3ObjectsData)
-      Sync.run(config, s3Client, md5HashGenerator, logInfo, logWarn)
+      Sync.run(config, s3Client, md5HashGenerator, logger)
       it("uploads nothing") {
         val expectedUploads = Map()
         assertResult(expectedUploads)(s3Client.uploadsRecord)
@@ -88,7 +87,7 @@ class SyncSuite
           RemoteKey("prefix/root-file-old") -> HashModified(rootHash, lastModified),
           RemoteKey("prefix/subdir/leaf-file") -> HashModified(leafHash, lastModified)))
       val s3Client = new RecordingClient(testBucket, s3ObjectsData)
-      Sync.run(config, s3Client, md5HashGenerator, logInfo, logWarn)
+      Sync.run(config, s3Client, md5HashGenerator, logger)
       it("uploads nothing") {
         val expectedUploads = Map()
         assertResult(expectedUploads)(s3Client.uploadsRecord)
@@ -116,7 +115,7 @@ class SyncSuite
         byKey = Map(
           deletedKey -> HashModified(deletedHash, lastModified)))
       val s3Client = new RecordingClient(testBucket, s3ObjectsData)
-      Sync.run(config, s3Client, md5HashGenerator, logInfo, logWarn)
+      Sync.run(config, s3Client, md5HashGenerator, logger)
       it("deleted key") {
         val expectedDeletions = Set(deletedKey)
         assertResult(expectedDeletions)(s3Client.deletionsRecord)
@@ -126,7 +125,7 @@ class SyncSuite
       val config: Config = Config(Bucket("bucket"), prefix, source = source, filters = List(Exclude("leaf")))
       val s3ObjectsData = S3ObjectsData(Map(), Map())
       val s3Client = new RecordingClient(testBucket, s3ObjectsData)
-      Sync.run(config, s3Client, md5HashGenerator, logInfo, logWarn)
+      Sync.run(config, s3Client, md5HashGenerator, logger)
       it("is not uploaded") {
         val expectedUploads = Map(
           "root-file" -> rootRemoteKey
@@ -146,7 +145,7 @@ class SyncSuite
 
     override def listObjects(bucket: Bucket,
                              prefix: RemoteKey)
-                            (implicit info: Int => String => Id[Unit]): S3ObjectsData =
+                            (implicit logger: Logger[Id]): S3ObjectsData =
       s3ObjectsData
 
     override def upload(localFile: LocalFile,
@@ -155,8 +154,7 @@ class SyncSuite
                         multiPartThreshold: Long,
                         tryCount: Int,
                         maxRetries: Int)
-                       (implicit info: Int => String => Id[Unit],
-                        warn: String => Id[Unit]): UploadS3Action = {
+                       (implicit logger: Logger[Id]): UploadS3Action = {
       if (bucket == testBucket)
         uploadsRecord += (localFile.relative.toString -> localFile.remoteKey)
       UploadS3Action(localFile.remoteKey, MD5Hash("some hash value"))
@@ -166,7 +164,7 @@ class SyncSuite
                       sourceKey: RemoteKey,
                       hash: MD5Hash,
                       targetKey: RemoteKey
-                     )(implicit info: Int => String => Id[Unit]): CopyS3Action = {
+                     )(implicit logger: Logger[Id]): CopyS3Action = {
       if (bucket == testBucket)
         copiesRecord += (sourceKey -> targetKey)
       CopyS3Action(targetKey)
@@ -174,7 +172,7 @@ class SyncSuite
 
     override def delete(bucket: Bucket,
                         remoteKey: RemoteKey
-                       )(implicit info: Int => String => Id[Unit]): DeleteS3Action = {
+                       )(implicit logger: Logger[Id]): DeleteS3Action = {
       if (bucket == testBucket)
         deletionsRecord += remoteKey
       DeleteS3Action(remoteKey)
diff --git a/domain/src/main/scala/net/kemitix/s3thorp/domain/Logger.scala b/domain/src/main/scala/net/kemitix/s3thorp/domain/Logger.scala
new file mode 100644
index 0000000..b2fd355
--- /dev/null
+++ b/domain/src/main/scala/net/kemitix/s3thorp/domain/Logger.scala
@@ -0,0 +1,10 @@
+package net.kemitix.s3thorp.domain
+
+trait Logger[M[_]] {
+
+  def debug(message: => String): M[Unit]
+  def info(message: => String): M[Unit]
+  def warn(message: String): M[Unit]
+  def error(message: String): M[Unit]
+
+}