Job Description

Senior Backend Engineer (Python)

• Title of Role: Senior Backend Engineer (Python)
• Location: San Francisco, CA, On-site
• Company Stage of Funding: A — Administrative and Support Services
• Office Type: On-site
• Salary: $180K–$220K

We're representing a Series A voice AI startup that is building a platform to fully automate phone calls using AI. Their technology enables businesses to manage both inbound and outbound calls—ranging from booking appointments to processing payments—without human agents. This company is tackling complex challenges at the intersection of voice infrastructure and backend systems, aiming to replicate and outperform traditional call center interactions.

What You Will Do

• Build and maintain Python-based state systems that drive voice AI interactions across complex, real-time conversations.
• Integrate and orchestrate multiple LLM providers, including prompt design and routing for seamless user experiences.
• Write clean, high-performance Python code leveraging asyncio and best practices for maintainability.
• Develop automated tests and validation suites to ensure system resilience and correctness.
• Monitor production systems, debug agent behavior, and continuously improve reliability and conversation quality.
• Design and optimize database schemas while operating both SQL and NoSQL databases in production.
• Implement comprehensive metrics, logging, and alerting to maintain high availability and detect issues early.

Ideal Candidate Background

• 5+ years of experience writing Python, with a strong focus on async web applications using FastAPI.
• Proven experience in backend architecture, microservices, and designing scalable systems.
• Strong understanding of integrating LLMs, external APIs, and managing complex stateful systems.
• Demonstrated ability to solve hard technical problems and communicate effectively with cross-functional teams.
• Experience with AWS and Kubernetes is beneficial, but Python expertise is paramount.

Preferred

• Familiarity with CI/CD pipelines and automated testing frameworks.
• Experience in a startup environment, showcasing grit and the ability to thrive under pressure.

Compensation and Benefits

The salary for this role ranges from $180K to $220K, with equity options between 0.1% and 0.45%. Join a fast-moving team focused on solving challenging technical problems and making a meaningful impact in the voice AI space.