An IDM-style download manager for Dart and Flutter — parallel chunked downloads, dynamic splitting, resume across restarts, and pluggable I/O.
An IDM-style download manager for Dart and Flutter — a faithful port of
@downloadx/core.
It downloads files in parallel chunks with random-access disk writes, splits slow chunks dynamically so fast connections never idle, survives process restarts, and recovers from misbehaving servers — with zero third-party dependencies (only the Dart SDK).
Unlike the TypeScript core, the Dart port ships a built-in dart:io
implementation (NativeIo) for both the file system
and the network, so a Flutter or Dart app gets working downloads with no
wiring. The I/O layer is still pluggable — pass your own [DownloadxIo] for
tests (an in-memory mock), web/IndexedDB, or a custom backend such as S3.
flutter pub add downloadx
flutter pub add downloadx