Senior Full Stack Engineer, Voice Agent (IVA)

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.