diff --git a/cli/src/main/scala/net/kemitix/thorp/cli/Program.scala b/cli/src/main/scala/net/kemitix/thorp/cli/Program.scala
index 6acd473..4198d6a 100644
--- a/cli/src/main/scala/net/kemitix/thorp/cli/Program.scala
+++ b/cli/src/main/scala/net/kemitix/thorp/cli/Program.scala
@@ -4,7 +4,6 @@ import net.kemitix.thorp.config._
 import net.kemitix.thorp.console._
 import net.kemitix.thorp.core.CoreTypes.CoreProgram
 import net.kemitix.thorp.core._
-import net.kemitix.thorp.domain.StorageQueueEvent
 import zio.ZIO
 
 trait Program {
@@ -24,62 +23,44 @@ trait Program {
   private def showVersion: ConfigOptions => Boolean =
     cli => ConfigQuery.showVersion(cli)
 
-  private def execute = {
+  private def execute =
     for {
       plan    <- PlanBuilder.createPlan
       archive <- UnversionedMirrorArchive.default(plan.syncTotals)
       events  <- applyPlan(archive, plan)
       _       <- SyncLogging.logRunFinished(events)
     } yield ()
-  }
 
   private def handleErrors(throwable: Throwable) =
-    for {
-      _ <- Console.putStrLn("There were errors:")
-      _ <- throwable match {
-        case ConfigValidationException(errors) =>
-          ZIO.foreach_(errors)(error => Console.putStrLn(s"- $error"))
-      }
-    } yield ()
+    Console.putStrLn("There were errors:") *> logValidationErrors(throwable)
 
-  private def applyPlan(
-      archive: ThorpArchive,
-      syncPlan: SyncPlan
-  ) = {
-    val zero: (Stream[StorageQueueEvent], Long) =
-      (Stream(), syncPlan.syncTotals.totalSizeBytes)
-    val actions = syncPlan.actions.zipWithIndex
+  private def logValidationErrors(throwable: Throwable) =
+    throwable match {
+      case ConfigValidationException(errors) =>
+        ZIO.foreach_(errors)(error => Console.putStrLn(s"- $error"))
+    }
+
+  private def applyPlan(archive: ThorpArchive, syncPlan: SyncPlan) =
     ZIO
-      .foldLeft(actions)(zero)((acc, action) =>
-        applyAction(archive, acc, action))
-      .map {
-        case (events, _) => events
-      }
-  }
+      .foldLeft(sequenceActions(syncPlan.actions))(
+        EventQueue(Stream.empty, syncPlan.syncTotals.totalSizeBytes))(
+        applyAction(archive)(_, _))
+      .map(_.events)
 
-  private def applyAction(
-      archive: ThorpArchive,
-      acc: (Stream[StorageQueueEvent], Long),
-      indexedAction: (Action, Int)
+  private def sequenceActions(actions: Stream[Action]) =
+    actions.zipWithIndex
+      .map({ case (a, i) => SequencedAction(a, i) })
+
+  private def applyAction(archive: ThorpArchive)(
+      queue: EventQueue,
+      action: SequencedAction
   ) = {
-    val (action, index)     = indexedAction
-    val (stream, bytesToDo) = acc
-    val remainingBytes      = bytesToDo - action.size
-    updateArchive(archive, action, index, stream, remainingBytes)
-      .map((_, remainingBytes))
+    val remainingBytes = queue.bytesInQueue - action.action.size
+    archive
+      .update(action, remainingBytes)
+      .map(events => EventQueue(queue.events ++ Stream(events), remainingBytes))
   }
 
-  private def updateArchive(
-      archive: ThorpArchive,
-      action: Action,
-      index: Int,
-      stream: Stream[StorageQueueEvent],
-      remainingBytes: Long
-  ) =
-    for {
-      event <- archive.update(index, action, remainingBytes)
-    } yield stream ++ Stream(event)
-
 }
 
 object Program extends Program
diff --git a/core/src/main/scala/net/kemitix/thorp/core/EventQueue.scala b/core/src/main/scala/net/kemitix/thorp/core/EventQueue.scala
new file mode 100644
index 0000000..850f664
--- /dev/null
+++ b/core/src/main/scala/net/kemitix/thorp/core/EventQueue.scala
@@ -0,0 +1,8 @@
+package net.kemitix.thorp.core
+
+import net.kemitix.thorp.domain.StorageQueueEvent
+
+case class EventQueue(
+    events: Stream[StorageQueueEvent],
+    bytesInQueue: Long
+)
diff --git a/core/src/main/scala/net/kemitix/thorp/core/SequencedAction.scala b/core/src/main/scala/net/kemitix/thorp/core/SequencedAction.scala
new file mode 100644
index 0000000..d9af258
--- /dev/null
+++ b/core/src/main/scala/net/kemitix/thorp/core/SequencedAction.scala
@@ -0,0 +1,6 @@
+package net.kemitix.thorp.core
+
+case class SequencedAction(
+    action: Action,
+    index: Int
+)
diff --git a/core/src/main/scala/net/kemitix/thorp/core/ThorpArchive.scala b/core/src/main/scala/net/kemitix/thorp/core/ThorpArchive.scala
index f415cb7..1244f38 100644
--- a/core/src/main/scala/net/kemitix/thorp/core/ThorpArchive.scala
+++ b/core/src/main/scala/net/kemitix/thorp/core/ThorpArchive.scala
@@ -16,8 +16,7 @@ import zio.{TaskR, ZIO}
 trait ThorpArchive {
 
   def update(
-      index: Int,
-      action: Action,
+      sequencedAction: SequencedAction,
       totalBytesSoFar: Long
   ): TaskR[Storage with Console with Config, StorageQueueEvent]
 
diff --git a/core/src/main/scala/net/kemitix/thorp/core/UnversionedMirrorArchive.scala b/core/src/main/scala/net/kemitix/thorp/core/UnversionedMirrorArchive.scala
index 5096846..d6969ff 100644
--- a/core/src/main/scala/net/kemitix/thorp/core/UnversionedMirrorArchive.scala
+++ b/core/src/main/scala/net/kemitix/thorp/core/UnversionedMirrorArchive.scala
@@ -12,18 +12,17 @@ case class UnversionedMirrorArchive(syncTotals: SyncTotals)
     extends ThorpArchive {
 
   override def update(
-      index: Int,
-      action: Action,
+      sequencedAction: SequencedAction,
       totalBytesSoFar: Long
   ): TaskR[Storage with Console with Config, StorageQueueEvent] =
-    action match {
-      case ToUpload(bucket, localFile, _) =>
+    sequencedAction match {
+      case SequencedAction(ToUpload(bucket, localFile, _), index) =>
         doUpload(index, totalBytesSoFar, bucket, localFile) >>= logEvent
-      case ToCopy(bucket, sourceKey, hash, targetKey, _) =>
+      case SequencedAction(ToCopy(bucket, sourceKey, hash, targetKey, _), _) =>
         Storage.copy(bucket, sourceKey, hash, targetKey) >>= logEvent
-      case ToDelete(bucket, remoteKey, _) =>
+      case SequencedAction(ToDelete(bucket, remoteKey, _), _) =>
         Storage.delete(bucket, remoteKey) >>= logEvent
-      case DoNothing(_, remoteKey, _) =>
+      case SequencedAction(DoNothing(_, remoteKey, _), _) =>
         Task(DoNothingQueueEvent(remoteKey))
     }
 
@@ -33,12 +32,16 @@ case class UnversionedMirrorArchive(syncTotals: SyncTotals)
       bucket: Bucket,
       localFile: LocalFile
   ) =
-    Storage.upload(localFile,
-                   bucket,
-                   UploadEventListener.Settings(localFile,
-                                                index,
-                                                syncTotals,
-                                                totalBytesSoFar))
+    Storage.upload(
+      localFile,
+      bucket,
+      UploadEventListener.Settings(
+        localFile,
+        index,
+        syncTotals,
+        totalBytesSoFar
+      )
+    )
 }
 
 object UnversionedMirrorArchive {