Software Engineer (Voice AI / Backend

Join a small, high-velocity team at a seed-stage AI voice platform building the next generation of voice AI agents for B2C businesses. You’ll own projects end-to-end, from core product decisions to technical architecture and production code, pushing frontier models to their limits to solve real customer problems across realtime audio, distributed systems, and applied AI., * Design and operate a distributed call scheduler that handles load, race conditions, time zones, retries, and provider limits across many concurrent calls.

• Extend agents beyond voice to multi-channel interactions (calls, WhatsApp, email) with shared memory and state across async and realtime conversations.
• Build memory and reasoning systems so agents maintain context throughout entire customer flows.
• Develop an AI coworker that configures agents, debugs issues, and integrates with CRMs, calendars, and email.
• Make every bad call easy to trace to root cause, and keep the system resilient when calls, workers, or providers fail.

• Production experience building and owning distributed systems at scale, including handling race conditions, load balancing, and fault tolerance.
• Strong proficiency in Python (FastAPI) and/or TypeScript (Node.js, Bun, Fastify), with a track record of shipping code end-to-end.
• Experience with real-time systems, audio processing, or voice infrastructure is a strong plus.
• Hands-on experience with LLMs, AI models, or agentic systems in production.
• Familiarity with PostgreSQL, Redis, or similar data stores in production environments.
• Experience with AWS, GCP, or Azure infrastructure.
• Familiarity with workflow orchestration tools such as Temporal, message queues, or similar.
• Experience with observability tooling such as OpenTelemetry, Honeycomb, or equivalent.
• React or full-stack experience is a welcome addition.
• Bias toward action: comfortable working independently, challenging assumptions, and driving outcomes.
• Team-first mindset with genuine care for business impact, not just the technology.

• Salary: €85,000 to €160,000 annually, depending on experience.
• Equity included.
• Visa sponsorship available.
• Relocation support available for candidates moving to Berlin.