Senior Full Stack Engineer, Voice Agent (IVA)

Job description

We are looking for a Senior Full Stack Engineer with strong experience in VoIP, SIP telephony, and conversational AI to join a Healthcare product.

You will help develop an intelligent voice solution that automates pharmacy calls, processes prescription-related requests, and connects patients with pharmacy staff when needed.

RESPONSIBILITIES:

- Develop and improve the voice agent, including conversation flows, patient verification, fallback scenarios, and call transfers;

- Build backend services and integrations with pharmacy management systems;

- Maintain the telephony layer, including SIP, RTP, codecs, DTMF, and PBX integrations;

- Optimize STT, LLM, and TTS pipelines for performance, accuracy, latency, and cost;

- Implement monitoring, call tracing, quality evaluation, and regression testing;

- Investigate production issues and contribute to architectural decisions.

REQUIREMENTS:

- Senior-level experience in backend or full-stack development;

- Strong knowledge of Python or TypeScript/Node.js;

- Hands-on production experience with VoIP and SIP telephony;

- Experience building IVR systems, voice bots, or LLM-powered voice agents;

- Understanding of STT, TTS, turn-taking, tool calling, and real-time voice processing;

- Experience integrating LLMs and third-party systems into production;

- Working knowledge of Asterisk or a similar PBX;

- Strong problem-solving, ownership, and communication skills.

WILL BE PLUS:

- Experience with LiveKit Agents, Vapi, Retell, jambonz, or similar platforms;

- Knowledge of Kamailio, OpenSIPS, FreeSWITCH, or MCP;

- Experience in Healthcare or other security-sensitive environments;

- Knowledge of React, Docker, Terraform, and observability tools.

MAIN BENEFITS:

- Flexible working hours;

- 25 paid days off and 10 sick/medical leaves;

- Additional paid days off for personal events;

- Maternity/Paternity leaves;

- Medical insurance;

- Self-development budget;

- Referral bonuses;

- Corporate events and gifts;

- Speaking Clubs;

- PE accounting and support.