diff --git a/codex/tarballs/directorydownloader.nim b/codex/tarballs/directorydownloader.nim
index ffc78c40..63e3fb30 100644
--- a/codex/tarballs/directorydownloader.nim
+++ b/codex/tarballs/directorydownloader.nim
@@ -23,7 +23,6 @@ import pkg/stew/byteutils
 import ../node
 import ../logutils
 import ../utils/iter
-import ../utils/safeasynciter
 import ../utils/trackedfutures
 import ../errors
 import ../manifest
@@ -89,115 +88,122 @@ proc createEntryHeader(
 proc fetchTarball(
     self: DirectoryDownloader, cid: Cid, basePath = ""
 ): Future[?!void] {.async: (raises: [CancelledError]).} =
-  echo "fetchTarball: ", cid, " basePath = ", basePath
-  # we got a Cid - let's check if this is a manifest (can be either
-  # a directory or file manifest)
-  without isM =? cid.isManifest, err:
-    warn "Unable to determine if cid is a manifest"
-    return failure("Unable to determine if cid is a manifest")
+  # we only need try/catch here because PR for checked exceptions is
+  # not yet merged
+  try:
+    echo "fetchTarball: ", cid, " basePath = ", basePath
+    # we got a Cid - let's check if this is a manifest (can be either
+    # a directory or file manifest)
+    without isM =? cid.isManifest, err:
+      warn "Unable to determine if cid is a manifest"
+      return failure("Unable to determine if cid is a manifest")
 
-  if not isM:
-    # this is not a manifest, so we can return
-    return failure("given cid is not a manifest: " & $cid)
+    if not isM:
+      # this is not a manifest, so we can return
+      return failure("given cid is not a manifest: " & $cid)
 
-  # get the manifest
-  without blk =? await self.node.blockStore.getBlock(cid), err:
-    error "Error retrieving manifest block", cid, err = err.msg
-    return
-      failure("Error retrieving manifest block (cid = " & $cid & "), err = " & err.msg)
+    # get the manifest
+    without blk =? await self.node.blockStore.getBlock(cid), err:
+      error "Error retrieving manifest block", cid, err = err.msg
+      return failure(
+        "Error retrieving manifest block (cid = " & $cid & "), err = " & err.msg
+      )
 
-  without manifest =? Manifest.decode(blk), err:
-    info "Unable to decode as manifest - trying to decode as directory manifest",
-      err = err.msg
-    # Try if it not a directory manifest
-    without manifest =? DirectoryManifest.decode(blk), err:
-      error "Unable to decode as directory manifest", err = err.msg
-      return failure("Unable to decode as valid manifest (cid = " & $cid & ")")
-    # this is a directory manifest
-    echo "Decoded directory manifest: ", $manifest
-    let dirEntry = TarballEntry(
-      kind: ekDirectory,
-      name: manifest.name,
+    without manifest =? Manifest.decode(blk), err:
+      info "Unable to decode as manifest - trying to decode as directory manifest",
+        err = err.msg
+      # Try if it not a directory manifest
+      without manifest =? DirectoryManifest.decode(blk), err:
+        error "Unable to decode as directory manifest", err = err.msg
+        return failure("Unable to decode as valid manifest (cid = " & $cid & ")")
+      # this is a directory manifest
+      echo "Decoded directory manifest: ", $manifest
+      let dirEntry = TarballEntry(
+        kind: ekDirectory,
+        name: manifest.name,
+        lastModified: getTime(), # ToDo: store actual time in the manifest
+        permissions: parseFilePermissions(cast[uint32](0o755)), # same here
+        contentLength: 0,
+      )
+      let header = self.createEntryHeader(dirEntry, basePath)
+      echo "header = ", header
+      await self.queue.addLast(header.toBytes())
+      self.printQueue()
+      var entryLength = header.len
+      let alignedEntryLength = (entryLength + 511) and not 511 # 512 byte aligned
+      if alignedEntryLength - entryLength > 0:
+        echo "Adding ", alignedEntryLength - entryLength, " bytes of padding"
+        var data = newSeq[byte]()
+        data.setLen(alignedEntryLength - entryLength)
+        await self.queue.addLast(data)
+      self.printQueue()
+
+      for cid in manifest.cids:
+        echo "fetching directory content: ", cid
+        if err =? (await self.fetchTarball(cid, basePath / manifest.name)).errorOption:
+          error "Error fetching directory content",
+            cid, path = basePath / manifest.name, err = err.msg
+          return failure(
+            "Error fetching directory content (cid = " & $cid & "), err = " & err.msg
+          )
+      echo "fetchTarball[DIR]: ", cid, " basePath = ", basePath, " done"
+      return success()
+
+    # this is a regular file (Codex) manifest
+    echo "Decoded file manifest: ", $manifest
+    let fileEntry = TarballEntry(
+      kind: ekNormalFile,
+      name: manifest.filename |? "unknown",
       lastModified: getTime(), # ToDo: store actual time in the manifest
-      permissions: parseFilePermissions(cast[uint32](0o755)), # same here
-      contentLength: 0,
+      permissions: parseFilePermissions(cast[uint32](0o644)), # same here
+      contentLength: manifest.datasetSize.int,
     )
-    let header = self.createEntryHeader(dirEntry, basePath)
-    echo "header = ", header
+    let header = self.createEntryHeader(fileEntry, basePath)
     await self.queue.addLast(header.toBytes())
     self.printQueue()
-    var entryLength = header.len
+    var contentLength = 0
+
+    proc onBatch(blocks: seq[Block]): Future[?!void] {.async.} =
+      echo "onBatch: ", blocks.len, " blocks"
+      for blk in blocks:
+        echo "onBatch[blk.data]: ", string.fromBytes(blk.data)
+        # await self.queue.addLast(string.fromBytes(blk.data))
+        await self.queue.addLast(blk.data)
+        self.printQueue()
+        contentLength += blk.data.len
+        # this can happen if the content was stored with padding
+        if contentLength > manifest.datasetSize.int:
+          contentLength = manifest.datasetSize.int
+        echo "onBatch[contentLength]: ", contentLength
+      success()
+
+    await self.node.fetchDatasetAsync(manifest, fetchLocal = true, onBatch = onBatch)
+
+    echo "contentLength: ", contentLength
+    echo "manifest.datasetSize.int: ", manifest.datasetSize.int
+    if contentLength != manifest.datasetSize.int:
+      echo "Warning: entry length mismatch, expected ",
+        manifest.datasetSize.int, " got ", contentLength
+
+    let entryLength = header.len + contentLength
     let alignedEntryLength = (entryLength + 511) and not 511 # 512 byte aligned
     if alignedEntryLength - entryLength > 0:
       echo "Adding ", alignedEntryLength - entryLength, " bytes of padding"
       var data = newSeq[byte]()
+      echo "alignedEntryLength: ", alignedEntryLength
+      echo "entryLength: ", entryLength
+      echo "alignedEntryLength - entryLength: ", alignedEntryLength - entryLength
       data.setLen(alignedEntryLength - entryLength)
+      echo "data.len: ", data.len
       await self.queue.addLast(data)
-    self.printQueue()
-
-    for cid in manifest.cids:
-      echo "fetching directory content: ", cid
-      if err =? (await self.fetchTarball(cid, basePath / manifest.name)).errorOption:
-        error "Error fetching directory content",
-          cid, path = basePath / manifest.name, err = err.msg
-        return failure(
-          "Error fetching directory content (cid = " & $cid & "), err = " & err.msg
-        )
-    echo "fetchTarball[DIR]: ", cid, " basePath = ", basePath, " done"
-    return success()
-
-  # this is a regular file (Codex) manifest
-  echo "Decoded file manifest: ", $manifest
-  let fileEntry = TarballEntry(
-    kind: ekNormalFile,
-    name: manifest.filename |? "unknown",
-    lastModified: getTime(), # ToDo: store actual time in the manifest
-    permissions: parseFilePermissions(cast[uint32](0o644)), # same here
-    contentLength: manifest.datasetSize.int,
-  )
-  let header = self.createEntryHeader(fileEntry, basePath)
-  await self.queue.addLast(header.toBytes())
-  self.printQueue()
-  var contentLength = 0
-
-  proc onBatch(
-      blocks: seq[Block]
-  ): Future[?!void] {.async: (raises: [CancelledError]).} =
-    echo "onBatch: ", blocks.len, " blocks"
-    for blk in blocks:
-      echo "onBatch[blk.data]: ", string.fromBytes(blk.data)
-      # await self.queue.addLast(string.fromBytes(blk.data))
-      await self.queue.addLast(blk.data)
       self.printQueue()
-      contentLength += blk.data.len
-      # this can happen if the content was stored with padding
-      if contentLength > manifest.datasetSize.int:
-        contentLength = manifest.datasetSize.int
-      echo "onBatch[contentLength]: ", contentLength
-    success()
-
-  await self.node.fetchDatasetAsync(manifest, fetchLocal = true, onBatch = onBatch)
-
-  echo "contentLength: ", contentLength
-  echo "manifest.datasetSize.int: ", manifest.datasetSize.int
-  if contentLength != manifest.datasetSize.int:
-    echo "Warning: entry length mismatch, expected ",
-      manifest.datasetSize.int, " got ", contentLength
-
-  let entryLength = header.len + contentLength
-  let alignedEntryLength = (entryLength + 511) and not 511 # 512 byte aligned
-  if alignedEntryLength - entryLength > 0:
-    echo "Adding ", alignedEntryLength - entryLength, " bytes of padding"
-    var data = newSeq[byte]()
-    echo "alignedEntryLength: ", alignedEntryLength
-    echo "entryLength: ", entryLength
-    echo "alignedEntryLength - entryLength: ", alignedEntryLength - entryLength
-    data.setLen(alignedEntryLength - entryLength)
-    echo "data.len: ", data.len
-    await self.queue.addLast(data)
-    self.printQueue()
-  echo "fetchTarball: ", cid, " basePath = ", basePath, " done"
-  return success()
+    echo "fetchTarball: ", cid, " basePath = ", basePath, " done"
+    return success()
+  except CancelledError as e:
+    raise e
+  except CatchableError as e:
+    error "Error fetching tarball", cid, err = e.msg
+    return failure("Error fetching tarball (cid = " & $cid & "), err = " & e.msg)
 
 proc streamDirectory(
     self: DirectoryDownloader, cid: Cid
diff --git a/codex/tarballs/tarballnodeextensions.nim b/codex/tarballs/tarballnodeextensions.nim
index 9aa36fbd..fb4c4b9e 100644
--- a/codex/tarballs/tarballnodeextensions.nim
+++ b/codex/tarballs/tarballnodeextensions.nim
@@ -21,24 +21,32 @@ proc fetchDirectoryManifest*(
   ## Fetch and decode a manifest block
   ##
 
-  if err =? cid.isManifest.errorOption:
-    return failure "CID has invalid content type for manifest {$cid}"
+  # we only need try/catch here because PR for checked exceptions is
+  # not yet merged
+  try:
+    if err =? cid.isManifest.errorOption:
+      return failure "CID has invalid content type for manifest {$cid}"
 
-  trace "Retrieving directory manifest for cid", cid
+    trace "Retrieving directory manifest for cid", cid
 
-  without blk =? await self.blockStore.getBlock(BlockAddress.init(cid)), err:
-    trace "Error retrieving directory manifest block", cid, err = err.msg
-    return failure err
+    without blk =? await self.blockStore.getBlock(BlockAddress.init(cid)), err:
+      trace "Error retrieving directory manifest block", cid, err = err.msg
+      return failure err
 
-  trace "Decoding directory manifest for cid", cid
+    trace "Decoding directory manifest for cid", cid
 
-  without manifest =? DirectoryManifest.decode(blk), err:
-    trace "Unable to decode as directory manifest", err = err.msg
-    return failure("Unable to decode as directory manifest")
+    without manifest =? DirectoryManifest.decode(blk), err:
+      trace "Unable to decode as directory manifest", err = err.msg
+      return failure("Unable to decode as directory manifest")
 
-  trace "Decoded directory manifest", cid
+    trace "Decoded directory manifest", cid
 
-  manifest.success
+    return manifest.success
+  except CancelledError as e:
+    raise e
+  except CatchableError as e:
+    trace "Error fetching directory manifest", cid, err = e.msg
+    return failure(e.msg)
 
 proc storeDirectoryManifest*(
     self: CodexNodeRef, manifest: DirectoryManifest