Senior Software Engineer, Voice AI / Backend

About the Role

Join a small engineering team building voice AI agents for customer-facing workflows. You will own projects end to end, from technical design through production, across applied AI, real-time audio, and distributed systems.

What You'll Do

• Build reliable voice AI systems, including retrieval, dynamic model routing, and testing speech transcription systems before production rollout.
• Design and operate distributed call scheduling systems that handle concurrent workloads, time zones, retries, race conditions, and provider limits.
• Extend agents across voice, messaging, and email, maintaining shared context between real-time and asynchronous interactions.
• Develop memory and reasoning systems that preserve context across customer workflows.
• Build tools that help configure agents, debug issues, and connect to CRM, calendar, and email systems.
• Improve tracing and resilience so teams can identify call failures and respond to issues with workers or providers.

What We're Looking For

• At least 2 years of experience building and owning production software, including distributed systems and end-to-end product delivery.
• Production experience with Python, FastAPI, or TypeScript, plus PostgreSQL, Redis, or similar data stores.
• Experience with real-time systems, audio processing, or voice infrastructure, and with LLMs, AI models, or agentic systems in production.
• Knowledge of distributed systems concepts such as race conditions, load balancing, and fault tolerance, plus experience with AWS, GCP, or Azure.
• Familiarity with workflow orchestration or messaging tools such as Temporal, and observability tools such as OpenTelemetry or Honeycomb.
• Full-stack experience with tools such as React is useful. Strong software fundamentals, independent problem-solving, and a focus on customer and business outcomes are important.
• Technologies include Python, FastAPI, LiveKit, TypeScript, Bun, Node.js, Fastify, React, PostgreSQL, Redis, Temporal, and major cloud platforms.

Compensation & Benefits

Compensation is €85,000 to €160,000 annually, plus equity. Visa sponsorship is available.

Location

On-site in Berlin, Germany.