Block a user
Missing atomic file writes on receiver (write-then-rename)
Incremental check causes per-file network round-trip -- batch it
Loader thread loads all file data into memory causing high memory usage
Fixed queue capacity 100 may cause pipeline stalls for varied file sizes
Missing heartbeat/keep-alive messages in protocol
Missing cancellation/abort mechanism in protocol
Missing --backup / --backup-dir flags for safe destructive operations
Missing --stats flag for transfer statistics summary
Missing --exclude-from / --include-from for pattern files
Missing --max-depth directory traversal limit flag
Missing --log-file option for persistent logging
Hardcoded queue capacity 100 should be configurable via --queue-size
Fixed 512-byte stack buffer for SSH user@host can truncate silently
No per-message receive timeout allows slow loris / hang DoS
MAX_DATA_SIZE = 1GB allows large memory allocation from network input
TLS client disables certificate verification when no CA is provided
Missing --timeout / --contimeout CLI flags for connection and I/O timeouts
Missing --quiet / --silent flag to suppress non-error output
No connection limit on server creates fork bomb DoS vector
Integer overflow in delta_signature_deserialize allocation