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 0f222da..88b1883 100644
--- a/cli/src/main/scala/net/kemitix/s3thorp/cli/Program.scala
+++ b/cli/src/main/scala/net/kemitix/s3thorp/cli/Program.scala
@@ -1,28 +1,20 @@
 package net.kemitix.s3thorp.cli
 
-import java.io.File
-
 import cats.Monad
 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.Sync
 import net.kemitix.s3thorp.domain.{Config, Logger}
 
 object Program {
 
   def apply[M[_]: Monad](config: Config): M[ExitCode] = {
-    val logger = new PrintLogger[M](config.verbose)
+    implicit val logger: Logger[M] = new PrintLogger[M](config.verbose)
     for {
       _ <- logger.info("S3Thorp - hashed sync for s3")
-      _ <- Sync.run[M](config, S3ClientBuilder.defaultClient, hashGenerator(logger), logger)
+      _ <- Sync.run[M](config, S3ClientBuilder.defaultClient)
     } yield ExitCode.Success
   }
 
-  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/Sync.scala b/core/src/main/scala/net.kemitix.s3thorp.core/Sync.scala
index f509563..5fd5d89 100644
--- a/core/src/main/scala/net.kemitix.s3thorp.core/Sync.scala
+++ b/core/src/main/scala/net.kemitix.s3thorp.core/Sync.scala
@@ -1,7 +1,5 @@
 package net.kemitix.s3thorp.core
 
-import java.io.File
-
 import cats.Monad
 import cats.implicits._
 import net.kemitix.s3thorp.aws.api.{S3Action, S3Client}
@@ -11,17 +9,15 @@ 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, Logger, MD5Hash, S3MetaData, S3ObjectsData}
+import net.kemitix.s3thorp.domain._
 
 object Sync {
 
   def run[M[_]: Monad](config: Config,
-                       s3Client: S3Client[M],
-                       md5HashGenerator: File => M[MD5Hash],
-                       logger: Logger[M]): M[Unit] = {
+                       s3Client: S3Client[M])
+                      (implicit logger: Logger[M]): M[Unit] = {
 
     implicit val c: Config = config
-    implicit val implLogger: Logger[M] = logger
 
     def metaData(s3Data: S3ObjectsData, sFiles: Stream[LocalFile]) =
       Monad[M].pure(sFiles.map(file => getMetadata(file, s3Data)))
@@ -34,7 +30,7 @@ object Sync {
 
     def copyUploadActions(s3Data: S3ObjectsData): M[Stream[S3Action]] =
       (for {
-        files <- findFiles(c.source, md5HashGenerator)
+        files <- findFiles(c.source, MD5HashGenerator.md5File[M](_))
         metaData <- metaData(s3Data, files)
         actions <- actions(metaData)
         s3Actions <- submit(actions)
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 2db8659..a0e3658 100644
--- a/core/src/test/scala/net/kemitix/s3thorp/core/SyncSuite.scala
+++ b/core/src/test/scala/net/kemitix/s3thorp/core/SyncSuite.scala
@@ -19,11 +19,6 @@ class SyncSuite
   val config = Config(Bucket("bucket"), prefix, source = source)
   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)
-  private val leafFile = LocalFile.resolve("subdir/leaf-file", leafHash, source, fileToKey)
-
-  private val md5HashGenerator = MD5HashGenerator.md5File[Id](_)
 
   def putObjectRequest(bucket: Bucket, remoteKey: RemoteKey, localFile: LocalFile): (String, String, File) =
     (bucket.name, remoteKey.key, localFile.file)
@@ -37,7 +32,7 @@ class SyncSuite
       val s3Client = new RecordingClient(testBucket, S3ObjectsData(
         byHash = Map(),
         byKey = Map()))
-      Sync.run(config, s3Client, md5HashGenerator, logger)
+      Sync.run(config, s3Client)
       it("uploads all files") {
         val expectedUploads = Map(
           "subdir/leaf-file" -> leafRemoteKey,
@@ -63,7 +58,7 @@ 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, logger)
+      Sync.run(config, s3Client)
       it("uploads nothing") {
         val expectedUploads = Map()
         assertResult(expectedUploads)(s3Client.uploadsRecord)
@@ -87,7 +82,7 @@ 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, logger)
+      Sync.run(config, s3Client)
       it("uploads nothing") {
         val expectedUploads = Map()
         assertResult(expectedUploads)(s3Client.uploadsRecord)
@@ -115,7 +110,7 @@ class SyncSuite
         byKey = Map(
           deletedKey -> HashModified(deletedHash, lastModified)))
       val s3Client = new RecordingClient(testBucket, s3ObjectsData)
-      Sync.run(config, s3Client, md5HashGenerator, logger)
+      Sync.run(config, s3Client)
       it("deleted key") {
         val expectedDeletions = Set(deletedKey)
         assertResult(expectedDeletions)(s3Client.deletionsRecord)
@@ -125,7 +120,7 @@ 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, logger)
+      Sync.run(config, s3Client)
       it("is not uploaded") {
         val expectedUploads = Map(
           "root-file" -> rootRemoteKey