Software Engineer, Voice - Milan

Key Responsibilities

• Own the real-time voice pipeline end-to-end. From audio ingress on the telephony edge, through streaming STT and turn-taking, to the agent brain and back out through streaming TTS. Every millisecond in between is yours.

• Engineer how fast the agent feels. Semantic end-of-turn detection, preemptive generation on partial transcripts, eager TTS, filler and backchannel strategies that mask tool calls. All measured on real 8kHz phone audio, not in a browser demo.

• Make turn-taking human. Barge-in that survives noisy lines. Endpointing policies that know the dialog state, so a caller never gets cut off mid-IBAN. The difference between an IVR and a conversation lives here.

• Raise voice quality on the channel that actually ships: the phone. Benchmark and A/B STT and TTS providers on real G.711 calls (Italian first: WER, naturalness, numbers and codes read right), exploit wideband/HD voice where the carrier allows it, and experiment with context-aware TTS and conversational speech models as they mature.

• Build the evaluation harness. Turn "this voice sounds better" into numbers we trust: per-stage latency budgets, turn-taking metrics, regression suites on recorded calls, quality gates before anything reaches a client.

• Keep production boringly reliable. Per-stage observability, live-call incident debugging (dead air, stuck turns, provider hiccups), graceful degradation when a vendor blinks.

• Track a weekly-moving ecosystem and turn it into strategy. New STT/TTS/speech-to-speech releases land every month. You decide what we integrate, what we self-host for EU compliance and data residency, and what we skip. And you make provider swaps cheap.

You will need

The filter is not your degree, and it's not years-of-experience arithmetic. It's having built it. Tell us about a real-time voice or audio system you designed and shipped: the latency budget, where it broke, and what you changed to make it feel right. That tells us more than any title.

• Real-time audio systems, shipped. You've built voice agents, telephony systems, conferencing or live-streaming products that ran in production. You know what it means to move audio over WebSockets/WebRTC, through codecs (G.711/μ-law, Opus), against a latency budget.

• The modern voice AI stack, hands-on. Streaming STT and TTS, VAD and turn detection, voice orchestration frameworks (Pipecat, LiveKit Agents or equivalent), speech-to-speech models. You have opinions on the trade-offs, grounded in things you've actually built, not blog posts.

• Strong software engineering. TypeScript/Node.js and/or Python, and the maturity to own a production service end-to-end: containers, cloud infrastructure, CI/CD, observability.

• A latency obsession. You think in milliseconds per stage, you instrument before you optimize, and you know the difference between measured and perceived latency, and how to exploit it.

• A product ear. You can hear the difference between a demo and a conversation, and you can translate what you hear into engineering priorities and measurable evals.

• An AI-native way of working. You use agentic coding tools (e.g. Claude Code) daily and you're good at directing them: setting up the problem, judging the output.

• Language Skills: Fluent English.

We will really like (but they are not required)

• Italian: our voice market is Italian-first, and you'll be tuning pronunciation, prosody and evals for it every week.

• Contact-center / CCaaS ecosystem experience: SIP trunking, SBCs, enterprise telephony platforms.

• ML audio experience: evaluating or fine-tuning ASR/TTS models, working with speech datasets.

• Elixir: our agent platform is built on it.

• Open source: contributions to open-source voice/audio projects.

What do we offer?

• A key role in one of Europe’s fastest-growing AI scale-ups, backed by a €10M investment from Azimut.

• A competitive salary in the range of 40-70k RAL, commensurate with experience + a performance-based Bonus.

• A flexible, remote-friendly work environment.

• Meal vouchers and Welfare programs to support your everyday life.

• Access to a dedicated education budget for continued learning and growth.

• Career Development Plan, ensuring a clear path for both personal and professional growth.

• Top-grade equipment, which may include a MacBook Air, iPhone, and other top-tier devices.

• Unlimited coffee.

• Company retreats in stunning locations throughout the year.

Why join us?

At indigo.ai you’ll be part of a fast-growing SaaS company where your ideas and work can turn into products used by millions. Join us and you’ll:

• Work with the most advanced AI technologies, shaping how enterprises across industries engage with their customers.

• Be part of a dynamic and passionate team, where everyone has a direct impact on company growth.

• Grow in a culture that values transparency, continuous learning, and career development, with clear paths for personal and professional progression.

• Enjoy a flexible, people-first environment, with remote-friendly policies, stunning retreats, and a strong focus on well-being.

• Contribute to our mission of reshaping how companies and people communicate worldwide.