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Senior Software Engineer, Billie AI team

Remote Serbia only full time USD 84k to 108k/yr

Key responsibilities

    What you'll do
  • Build and improve AI voice and chat agents that handle thousands of patient conversations every day.
  • Work on real-time systems where low latency, high concurrency, and reliability are critical.
  • Develop AI-powered cost estimation algorithms using LLMs and statistical analysis of historical data.
  • Analyze production data, identify patterns, form hypotheses, test hypotheses, improve accuracy.
  • Design backend systems that handle high traffic, external integrations, and complex workflows.
  • Own features end to end. From understanding the business problem to implementation, production monitoring, and measuring results.
  • Build metrics and dashboards to understand how our products perform and where they need improvement.
  • Make pragmatic engineering decisions. Know when to move fast and when correctness and reliability cannot be compromised.
  • Challenge product ideas, propose better solutions, and defend your decisions with data and business reasoning.

Required qualifications

    What we're looking for
  • Strong Python and PostgreSQL experience.
  • Solid system design skills. Ability to make and explain architectural decisions.
  • Experience with data analysis, SQL, and building metrics to support decisions.
  • Experience using AI coding tools in your daily workflow.
  • Strong product and business thinking -- Ability to understand business requirements, evaluate trade-offs, and make decisions based on customer and business impact.
  • End-to-end ownership -- Experience taking projects from initial requirements through design, implementation, deployment, and measuring results.


  • Nice to have
  • Experience writing and evaluating prompts for production AI systems.
  • Experience building AI-powered products.

Source: the employer's careers page. Last checked 2026-10-25. Posted 2026-10-21.

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