Aituber — AI Virtual Idol Interaction Platform

A real-time interaction platform featuring live chat, karaoke synchronization, and YouTube Live streaming integration, built to handle thousands of concurrent users.

Challenge
The platform needed to sustain high-concurrency WebSocket connections for simultaneous chat, reactions, and karaoke events while also processing and syncing audio/video streams for YouTube Live — all with sub-100ms latency requirements.
Solution
Built a segmented ActionCable architecture backed by Redis pub/sub for message fan-out. Integrated FFmpeg with a Node.js sidecar to handle real-time audio/video stream processing. Offloaded heavy background work to Sidekiq to keep the main request cycle lean.

Impact Metrics

Comparison before and after implementation.

Concurrent WebSocket Connections
~200 2,000+
Message Delivery Latency
> 500ms < 80ms

Key Achievements

Real-Time Scale
Sustained 2,000+ concurrent WebSocket connections per instance with zero dropped messages.
YouTube Live Integration
Delivered stable live streaming with synchronized audio/video using FFmpeg + Node.js pipeline.
Karaoke Sync Engine
Built precise lyric synchronization broadcast via ActionCable with < 100ms drift tolerance.

Technical Visuals

Live Stream Dashboard
Real-time viewer interaction panel during a live session