+@item
+Optimization: do not close file descriptor of the file we download
+online. Previously each chunk lead to expensive open/close calls.
+
+@item
+Online downloaded files are saved with @file{.nock} (non-checksummed)
+suffix, waiting either for @command{nncp-check}, or online daemons to
+perform integrity check.
+
+@item
+Optimization: files, that are not resumed, are checksummed immediately
+during the online download, skipping @file{.nock}-intermediate step.
+
+@item
+Ability to store encrypted packet's header in @file{.hdr} file, close to
+the packet itself. That can greatly increase performance of packets
+listing on filesystems with big block's size.
+