OpenDM - Open Source Download Manager

A high-performance, open-source download manager built with Rust + Tauri

Features • Installation • Usage • Roadmap • Contributing • License

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Table of Contents

1. About The Project
2. Features
3. Tech Stack
4. Performance
5. Installation
6. Usage
7. Screenshots
8. Roadmap
9. Contributing
10. License
11. Acknowledgments

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About The Project

OpenDM is an open-source download manager designed to be a free, high-performance alternative to Internet Download Manager (IDM). Built with modern technologies like Rust and Tauri, it offers lightning-fast download speeds through multi-threaded downloading while maintaining a familiar, IDM-compatible user interface.

Why OpenDM?

Problem	OpenDM Solution
IDM is paid software	Completely free and open source
IDM is Windows-only (officially)	Cross-platform foundation
Limited customization	Full control over your downloads
Closed source	Transparent, auditable code
Slow browser downloads	5-8x faster with multi-threading

Target Users

• Power users who need fast, reliable downloading
• Open source enthusiasts who prefer free software
• Users migrating from IDM who want a free alternative
• Developers who want to customize their download experience

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Features

Core Features

Feature	Status	Description
Multi-threaded Download	✅ Stable	Splits files into 4-32 chunks for parallel downloading
Pause/Resume	✅ Stable	Full support for pausing and resuming downloads
Progress Tracking	✅ Stable	Real-time speed and ETA calculation
Chunk Visualization	✅ Stable	Individual chunk progress display
Download Categories	✅ Stable	Organize by All/Downloading/Completed/Queued
System Tray	✅ Stable	Minimize to system tray
Crash-Safe Progress	✅ Stable	Periodic saves every 5s, resume after crash
Smart Retries	✅ Stable	Exponential backoff (1s→60s), max 5 retries

Upcoming Features

Feature	Status	Description
Browser Integration	🔄 Planned	Browser extension to capture downloads
Queue Scheduling	🔄 Planned	Schedule downloads for specific times
Batch Downloads	🔄 Planned	Grab multiple links at once
Bandwidth Limiting	🔄 Planned	Control download/upload speeds
Custom Categories	🔄 Planned	Create custom download folders
FTP Support	🔄 Planned	Add FTP protocol support

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Tech Stack

Architecture

┌─────────────────────────────────────────────────────────────┐
│                    UI Layer (React + TypeScript)            │
│   Components │ Stores (Zustand) │ Hooks                    │
├─────────────────────────────────────────────────────────────┤
│                    Tauri IPC Bridge                         │
├─────────────────────────────────────────────────────────────┤
│                 Rust Backend (Tauri Commands)               │
│  ┌──────────────────────────────────────────────────────┐  │
│  │              Download Engine (Tokio)                   │  │
│  │  ┌─────────┐ ┌─────────┐ ┌─────────┐ ┌─────────┐   │  │
│  │  │Chunk 1 │ │Chunk 2 │ │Chunk 3 │ │Chunk N │   │  │ ← 8-16 async tasks
│  │  │(reqwest)│ │(reqwest)│ │(reqwest)│ │(reqwest)│   │  │
│  │  └────┬────┘ └────┬────┘ └────┬────┘ └────┬────┘   │  │
│  │       │           │           │           │          │  │
│  │       └───────────┼───────────┼───────────┘          │  │
│  │                   ▼                                   │  │
│  │          ┌──────────────────┐                        │  │
│  │          │  File Assembler   │                        │  │
│  │          │  (Random Access)  │                        │  │
│  │          └──────────────────┘                        │  │
│  └──────────────────────────────────────────────────────┘  │
└─────────────────────────────────────────────────────────────┘

Technology Details

Layer	Technology	Purpose
Desktop Shell	Tauri 2.0	Lightweight native window (~14MB)
Backend Runtime	Tokio	Async runtime for concurrent downloads
HTTP Client	reqwest	High-performance HTTP with HTTP/2
UI Framework	React 18	Modern reactive user interface
State Management	Zustand	Lightweight state management
Build Tool	Vite	Fast development & building

Dependencies

Rust (src-tauri/Cargo.toml)

tokio = { version = "1", features = ["full"] }
reqwest = { version = "0.12", features = ["stream", "rustls-tls"] }
tauri = { version = "2", features = ["tray-icon", "devtools"] }
tracing = "0.1"
futures = "0.3"
uuid = { version = "1", features = ["v4"] }

Frontend (package.json)

{
  "react": "^18.2.0",
  "zustand": "^4.5.0",
  "@tauri-apps/api": "^2.0.0",
  "lucide-react": "^0.400.0"
}

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Performance

Benchmark Results

Metric	OpenDM	Browser (Chrome)	IDM
Download Speed	5-8x faster	baseline	comparable
Startup Time	< 500ms	-	~1-2s
Memory Usage	< 100MB	~200MB+	~50MB
Binary Size	~14MB	N/A	~10MB

Performance Optimizations

Technique	Implementation
Dynamic Chunking	8 chunks <100MB, 16 chunks <1GB, 32 chunks >1GB
Async I/O	Tokio runtime with multi-threaded work-stealing
HTTP/2 Support	Single connection, multiple streams
Connection Pooling	Reuse TCP connections across chunks
TCP Tuning	TCP_NODELAY, keepalive settings
Zero-Copy Write	Direct file writes without buffering
Crash Recovery	Auto-resume from .progress_{chunk} files
Smart Retries	5 retries with exponential backoff (1s→60s)

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Installation

Prerequisites

Requirement	Version	Notes
Node.js	18+	For building frontend
Rust	1.70+	For building backend
Cargo	Included	Comes with Rust
Windows	10/11	Primary target platform

Quick Install (Pre-built)

Download the latest release from GitHub Releases:

# Using PowerShell (Windows)
# Download the .exe installer
Start-Process "OpenDM_1.0.0_x64-setup.exe"

Build from Source

# Clone the repository
git clone https://github.com/henglyrepo/Open-Download-Manager.git
cd Open-Download-Manager

# Install dependencies
npm install

# Build for production
npm run tauri build

# Run in development mode
npm run tauri dev

Build Output

After building, you'll find:

src-tauri/target/release/
├── opendm.exe              # Standalone executable (~14MB)
└── bundle/
    └── nsis/
        └── OpenDM_1.0.0_x64-setup.exe  # Windows installer

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Usage

Getting Started

1. Launch OpenDM - Run opendm.exe
2. Add a Download - Click the + Add URL button or press Ctrl+N
3. Enter URL - Paste the download link
4. Get File Info - Click "Get File Info" to fetch file details
5. Choose Location - Select where to save the file
6. Start Download - Click "Start Download"

User Interface

┌────────────────────────────────────────────────────────────┐
│ [Icon] OpenDM                              [_] [□] [X]   │
├────────────────────────────────────────────────────────────┤
│ [+Add URL] [▶Start] [⏸Pause] [■Stop] [🗑Delete] [⚙]   │
├──────────────┬─────────────────────────────────────────────┤
│ CATEGORIES  │ File    │ Size │ %   │ Speed │ Status      │
│ ├─ All (24) │ file1   │100MB│ 45% │ 5MB/s │ ⬇ Downloading│
│ ├─ Downloading│ video  │500MB│ 12% │ 8MB/s │ ⬇ Downloading│
│ ├─ Completed │ doc.pdf │ 10MB│ --  │ --    │ ✓ Completed │
│ ├─ Queued   │ archive │ 1GB │ --  │ --    │ ⏳ Queued   │
│ └─ Scheduled │         │     │     │       │             │
├──────────────┴─────────────────────────────────────────────┤
│ [3] Downloads │ 13MB/s │ 1.6GB downloaded    [Tray: ▼]  │
└────────────────────────────────────────────────────────────┘

Keyboard Shortcuts

Shortcut	Action
Ctrl+N	Add new download
Ctrl+Enter	Start selected download
Space	Pause/Resume selected
Delete	Delete selected download
Ctrl+,	Open Settings

Download Progress Dialog

┌─────────────────────────────────────┐
│ Downloading: video.mp4               │
├─────────────────────────────────────┤
│ ████████████░░░░░░░░░  45%         │
├─────────────────────────────────────┤
│ Chunk 1: ██████████░░  80%         │
│ Chunk 2: ████████░░░░  60%         │
│ Chunk 3: █████████░░░  70%         │
│ Chunk 4: ████░░░░░░░░  30%         │
├─────────────────────────────────────┤
│ Speed: 8.2 MB/s  ETA: 1:23         │
│ Resume: Supported ✓                 │
└─────────────────────────────────────┘
        [⏸Pause]  [Cancel]

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Screenshots

Main Window

Add Download Dialog

┌─────────────────────────────────────────┐
│  Add New Download                         │
├─────────────────────────────────────────┤
│  URL:  [https://example.com/file.zip  ] │
│                                         │
│  [Get File Info]                        │
│  ┌─────────────────────────────────────┐│
│  │ File: test.zip                      ││
│  │ Size: 100 MB                        ││
│  │ Type: application/zip               ││
│  └─────────────────────────────────────┘│
│                                         │
│  Save to: [C:\Users\Downloads\test.zip]│
│                                         │
│            [Cancel]  [Start Download]   │
└─────────────────────────────────────────┘

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Roadmap

Version 1.0.0 (Current)

• Multi-threaded downloading
• Pause/Resume support
• Progress tracking
• Basic UI (IDM-compatible)
• System tray integration
• Crash-safe progress (periodic saves)
• Smart retries with exponential backoff

Version 1.1.0 (Planned)

• Download queue management
• Multiple simultaneous downloads
• Download categories/folders

Version 1.2.0 (Planned)

• Browser extension (Chrome/Edge/Firefox)
• Video detection on web pages
• Batch link grabbing

Version 2.0.0 (Future)

• Bandwidth limiting
• Download scheduling
• FTP support
• Cross-platform (Linux/macOS)

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Contributing

Contributions are welcome! Here's how you can help:

Development Setup

# Fork and clone the repository
git clone https://github.com/henglyrepo/Open-Download-Manager.git
cd Open-Download-Manager

# Install frontend dependencies
npm install

# Run in development mode
npm run tauri dev

Coding Standards

• Rust: Follow rustfmt and clippy guidelines
• TypeScript: Use ESLint with standard config
• Commits: Use conventional commits format
• Testing: Add tests for new features

Pull Request Process

1. Fork the repository
2. Create a feature branch (git checkout -b feature/amazing-feature)
3. Commit your changes (git commit -m 'Add amazing feature')
4. Push to the branch (git push origin feature/amazing-feature)
5. Open a Pull Request

Ways to Contribute

Type	Description
🐛 Bug Reports	Submit via GitHub Issues
💡 Feature Requests	Suggest new features
📖 Documentation	Improve docs/README
💻 Code	Submit PRs for features/fixes
🌍 Translations	Localize the application

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License

Distributed under the MIT License. See LICENSE for more information.

MIT License

Copyright (c) 2024 OpenDM Team

Permission is hereby granted, free of charge, to any person obtaining a copy
of this software and associated documentation files (the "Software"), to deal
in the Software without restriction, including without limitation the rights
to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
copies of the Software, and to permit persons to whom the Software is
furnished to do so, subject to the following conditions:

The above copyright notice and this permission notice shall be included in all
copies or substantial portions of the Software.

THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
SOFTWARE.

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Acknowledgments

Inspired By

• Internet Download Manager (IDM) - The gold standard for Windows download managers
• Xtreme Download Manager - Another open-source alternative
• Aria2 - The ultimate download utility

Resources

• Tauri Documentation
• Rust Book
• React Documentation
• Tokio Async Runtime

Special Thanks

• Tauri Team - For the amazing framework
• Contributors - For making this project possible

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Contact

Channel	Link
🌐 Website	opendm.dev
🐛 Issues	GitHub Issues
💬 Discussions	GitHub Discussions
⭐ Star us	GitHub

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⭐ Star us on GitHub if you find this project useful!

Made with ❤️ by the OpenDM Team