Senior AI Engineer -- Voice AI
Fully Remote | CET ±2 Europe or UK
Highly competitive base salary
Production phone agents | Full technical ownership | Legal AI scale-up
I'm partnering with a fast-growing European Legal AI company that is looking for its first dedicated Senior Voice AI Engineer.
The business has raised €6.5m in seed funding, grown to around 75 people, and is already supporting more than 2,000 lawyers through an AI platform that automates client intake, communication, document collection and case preparation.
At the heart of the platform is a live AI phone assistant handling real inbound and outbound calls for paying law firms.
The product has achieved clear market validation. The next challenge is technical.
The current voice architecture was built quickly by strong Applied AI generalists to prove the market. It now needs to be redesigned and scaled by someone who has been deep in production Voice AI from the start.
This is a rare opportunity to rebuild a live production voice system while keeping real customers and calls running.
What you'll own:
- Full technical ownership of the production Voice AI stack
- Redesigning and incrementally rebuilding the existing architecture
- STT → LLM → TTS pipelines
- Telephony across PSTN, SIP and WebRTC
- Turn-taking, interruption handling and barge-in
- Latency, reliability and conversational quality
- LLM orchestration, tool calling, RAG and model selection
- Voice evaluation, testing and observability
- Multilingual phone-agent performance across European markets
- Engineering standards for production AI systems
This is not a chatbot role. The hard requirement is that you have personally built and shipped a real phone agent handling real users and real phone calls.
Relevant experience could include:
- LiveKit Agents, Vapi, Pipecat, Retell, Daily Bots, Bland
- Twilio or Telnyx
- ElevenLabs, Deepgram, Soniox, AssemblyAI, Cartesia
- OpenAI Realtime API, Gemini Live
You should bring:
- 5+ years of professional software engineering experience
- 1--2+ years focused specifically on Voice AI
- Strong Python engineering skills
- Deep understanding of STT, LLM and TTS pipelines
- Hands-on telephony experience
- Experience shipping production LLM features end-to-end
- Strong knowledge of latency, interruptions and turn-taking
- Experience with evals, observability and production reliability
- Confidence taking ownership of architecture through implementation
- Availability to work remotely within CET ±2
Useful extras:
- High-volume outbound calling
- Concurrency, retries and compliance
- German, French, Spanish or Italian
- WebRTC fundamentals
- Voice-specific evaluation platforms
- Experience rebuilding live production systems
Why this role stands out:
- You will be the company's first dedicated Voice AI specialist
- The product is already live with real customers
- You will shape the architecture for years to come
- Around 50% of the company sits in Product and Engineering
- You will work directly with the AI Lead, Head of Engineering and CTO
- Highly autonomous, senior-weighted engineering team
- Fully remote across European time zones
- Fast interview process designed to complete within three weeks
The culture is fast-moving, highly accountable and ownership-led. This will suit someone who enjoys ambiguity, challenges assumptions and is comfortable rebuilding critical systems while they remain live.
If you have genuinely shipped production phone agents and want full ownership of a product with real users, message me directly with a brief overview of the phone agent you built, the stack, call volume and what you personally owned.
