A VoIP application written in Rust. Think Discord or TeamSpeak, but self-hosted and open-source.

Status: Early Development

• Intro
• Features
• Motivation
• How to Start
• Architecture
• Acknowledgments

VoiceApp is a set of binaries that let you run your own voice chat:

• desktop - Reference desktop client built with the SDK
• server - Central server acting as both management and voice relay server
• protocol - Binary protocol for client-server communication
• sdk - SDK for building custom clients or integrations (includes encoding, resampling, networking)
• extras - Additional tools

• 🎙️ Real-time voice communication with unlimited peers
• 👥 Group chat messaging
• 🎧 Wide audio device support with auto-resampling
• ⚡ Lightweight custom binary protocol

I wanted to understand how voice communication actually works - not just use existing libraries (WebRTC), but build it from the ground up. This meant learning:

1. VoIP from scratch - How does audio get from your mic to someone else's speakers? Audio capture, Opus encoding, UDP networking, jitter buffers, resampling. All the pieces that make real-time voice work.

2. Rust - Systems programming with actual constraints: low latency, concurrent audio streams, memory safety. Using async/await for networking, dealing with FFI for audio libraries, understanding ownership in practice.

3. AI-assisted development - Writing code with LLMs as a tool. Learning prompting, using MCP servers, figuring out where AI helps and where it doesn't.

# Build the server
cargo build --release -p voiceapp-server

# Build the desktop client
cargo build --release -p voiceapp-desktop

# Start the server (runs on 127.0.0.1:9001 for management, 127.0.0.1:9002 for voice)
./target/release/voiceapp-server

# Start the desktop client
./target/release/voiceapp-desktop

Centralized server model. Easier to implement and avoids P2P issues like NAT traversal and bandwidth scaling.

• Desktop Client: GUI (iced), mic capture (cpal), Opus encoding, UDP for voice, TCP for presence
• Server: TCP for login/presence/channels, UDP relay for voice packets

Huge thanks to:

• Mikhail Kutsov - For the desktop application design
• iced - Cross-platform GUI framework that made building the desktop client possible
• neteq - Solid jitter buffer implementation that handles packet loss and timing
• rubato - High-quality and performant audio resampling, brings support for many devices
• Phosphor Icons - Icon family used throughout the UI
• Rubik Font - Typeface used in the application
• Rusu Gabriel - For the sound effects used in UI notifications