Voice AI Engineer

Intro For this position we are only looking for candidates located in Greece, Germany or Austria . Nairon GmbH is a Swiss startup building AI voice agents that answer and make phone calls for businesses. Our platform runs real-time conversations over the phone and on the web, connected to our customers' telephony and business tools. We value clear communication, thoughtful engineering, and a collaborative approach to problem-solving. Join us as we continue to develop tools that make a difference.

Tasks

• Improving turn-taking: when the agent speaks, waits, yields or gets interrupted, including voice activity and end-of-turn detection.
• Cutting end-to-end latency across speech recognition, language models and speech synthesis, and making provider failover seamless.
• Optimising how we use LLMs in conversation: prompting, tool calls, streaming and speculative or parallel requests.
• Serving our own speech models (STT and TTS) on GPUs, measuring throughput and time to first audio.
• Fine-tuning speech and language models for our customers' languages and voices.
• Building evaluation: test calls, benchmarks and quality metrics that tell us when a change really helps.

Requirements

• Experience: A senior or strong mid-level engineer with production experience in real-time audio, conversational AI or ML model serving.
• Technical Skills: Required: Strong Python , including asyncio and streaming pipelines. Hands-on work with speech (STT, TTS, VAD) and LLM APIs in latency-sensitive systems. Model serving on GPUs, for example with vLLM or similar, and the basics of batching and memory limits.
• Nice to have: LiveKit Agents , pipecat or WebRTC. Fine-tuning (LoRA or full) of speech or language models. Audio signal processing such as echo cancellation or noise suppression. German, or experience with German-language speech data.
• Communication: English proficiency is essential , both written and spoken, as it is the working language for all positions.
• Soft Skills: You measure before and after, and trust numbers over impressions. Ownership of a problem from the first bad call to the fix in production.

Benefits

• Flexible Work Setup: Work fully remotely or from a co-working space - whichever suits you best.
• Equipment Provided: Company laptop and phone provided for all employees.
• Collaborative Environment: Join a small, agile team where your contributions have a direct impact.
• Growth Opportunities: Work across the whole voice stack, from model serving to the conversation the caller hears.