Software Engineer, Voice AI / Backend

ABOUT THE ROLE Join a small, fast-moving engineering team building voice AI agents for customer-facing workflows. You will own projects end to end, working across applied AI, real-time audio, and distributed systems to solve practical customer problems. WHAT YOU'LL DO - Build reliable voice AI systems, including retrieval-augmented generation, dynamic model routing, and testing transcription services before production rollout. - Design and operate a distributed call scheduler that manages concurrency, race conditions, time zones, retries, and provider limits. - Extend agents across voice, messaging, and email, with shared memory and state for asynchronous and real-time conversations. - Develop memory and reasoning systems that preserve context throughout customer workflows. - Build AI-assisted tools for configuring agents, debugging issues, and connecting to business systems such as CRMs, calendars, and email. - Improve tracing and resilience so failures across calls, workers, and providers can be diagnosed and handled effectively. WHAT WE'RE LOOKING FOR - Production experience building and owning distributed product systems, and a track record of shipping projects end to end. - Experience with Python, FastAPI, or TypeScript in production, plus PostgreSQL, Redis, or comparable data stores. - Background in real-time systems, audio processing, or voice infrastructure, and experience with concurrency, load balancing, or fault tolerance. - Experience shipping LLM, AI model, or agentic systems, and working with AWS, GCP, or Azure. - Familiarity with workflow orchestration or message queues, observability tools, and full-stack development is useful. - Technologies include LiveKit, Bun, Node.js, Fastify, React, Temporal, and OpenTelemetry. - Strong software fundamentals, independent problem-solving, and a team-oriented focus on customer and business outcomes. COMPENSATION & BENEFITS €85,000 to €160,000 annually, plus equity. Visa sponsorship is available. Relocation support is available. LOCATION On-site in Berlin, Germany.