We run a product with a real-time AI voice — It works and handles real calls today. However
We need an expert voice-AI engineer to obsess over two things: making it sound genuinely human, and making it respond instantly. Everything else is secondary.

The mission: humanness + speed
Make it human. Callers should forget they're talking to a machine — natural prosody, warmth, and pacing from our TTS; clean barge-in/interruption handling and endpointing so it never talks over people or leaves dead air; natural confirmation of spelled-out emails and phone numbers; no stiff "AI" phrasing.

Make it rapid. We're around ~5s voice-to-voice and want to get under 2s without hurting naturalness. We have a tuning plan (VAD/endpointing, LLM prefix caching + speculative decoding, STT decode params, TTS warm-up/streaming, pipeline parallelism) — validate, execute, and push it further. Every 500ms cut makes it feel more alive.
Our current TTS — this is what you'll tune




We are standardizing on two TTS engines and want an expert to get maximum humanness and minimum latency out of these specifically (not to swap in new ones):

Local / self-hosted Kokoro TTS on our own GPU (NVIDIA A6000) — low-latency, no per-minute cost.
Fish Audio TTS (s2.1-pro) — our most expressive, human-sounding voice.

Direct, hands-on Fish Audio and/or Kokoro experience is a major plus — knowing their params, streaming behavior, warm-up, and reference voices.
Rest of the stack
Pipecat + Daily WebRTC → Whisper STT + Qwen via vLLM → local Kokoro.
LiveKit Agents → Inworld STT + LLM → Fish Audio or Kokoro (per call).
Python · asyncio · aiohttp · Docker · Postgres (call/turn metrics).
Must-have experience
Shipped real-time, low-latency voice agents to production — made one sound human AND respond fast, and can prove it with numbers.
Deep knowledge of the STT → LLM → TTS streaming pipeline and where both the milliseconds and the naturalness come from.
Hands-on with Fish Audio and/or Kokoro (or very close analogues), plu

📌 Voice AI Expert to Make Our Voice Bot Faster (India)
🏢 BizFinder.ai
📍 India