Senior Infrastructure Engineer

Location: San Francisco, CA (Onsite - Jackson Square)

Compensation Range: $120,000 - $200,000 + Meaningful Equity

About the Company

Our client is a San Francisco-based pioneer, on a mission to fundamentally change how customers interact with businesses. They are building a platform that empowers enterprises to deploy AI-powered phone agents at a massive scale. Backed by $65 million in funding from top-tier firms like Emergence Capital and Scale Venture Partners, and supported by the founders of Twilio, Affirm, and ElevenLabs, this rapidly growing team is tackling one of the most complex and impactful challenges at the intersection of AI and real-time communication.

About the Role

As a Senior Infrastructure Engineer, you will be tasked with building the mission-critical backbone that enables millions of AI-powered phone conversations. This role is not about simply keeping the lights on; it is about architecting and scaling distributed systems that handle real-time voice processing, machine learning inference, and complex telephony integrations. The reliability, latency, and scalability of the systems you build will directly determine the success of our enterprise customers' most critical communication channels.

What You'll Do

1. Design Scalable Architecture: Architect and build distributed systems using Kubernetes to manage high-volume, real-time voice processing with stringent latency and reliability requirements.
2. Build ML Infrastructure: Create, optimize, and maintain the infrastructure that supports our AI models, from training pipelines to real-time, multi-region inference serving.
3. Integrate Telephony Systems: Maintain and evolve robust, secure connections between our platform and complex enterprise telephony systems, including SIP trunks and VoIP infrastructure.
4. Ensure Platform Reliability: Implement comprehensive monitoring, alerting, and incident response systems to guarantee enterprise-grade uptime and performance 24/7.
5. Anticipate Scaling Challenges: Proactively solve for scaling challenges in an environment where call volume grows exponentially; infrastructure must always stay ahead of demand.
6. Uphold Security and Compliance: Implement and enforce security best practices and compliance protocols required by enterprise customers in regulated industries.

Interesting Problems You'll Own

1. Old Meets New: You will have the creative freedom to design a novel architecture that wrangles decades-old telephony protocols with cutting-edge technologies, defining a new standard for the industry.
2. Architecting for Massive Scale: You will be deeply invested in designing unique solutions that allow our platform to seamlessly match any level of customer call volume, no matter how large.
3. Mastering Streaming Architectures: You will build, maintain, and ensure the reliability, failover, and scaling of our critical stream-based audio traffic.

What Makes You a Great Fit

1. 5+ years of experience building and scaling distributed systems, with deep expertise in cloud infrastructure (AWS or GCP preferred).
2. Proven experience with high-throughput, low-latency, real-time systems (e.g., streaming, real-time processing).
3. A genuine passion for infrastructure fundamentals. You can effortlessly explain the intricacies of TLS, illustrate various load-balancing strategies, and geek out about the obscure technical topic you read about last night.
4. A proven track record in a fast-growing startup environment, where you've worn multiple hats and thrived on solving ambiguous problems as they arise.
5. You are opinionated and driven to find the best technical path, but you collaborate effectively, seeking compromise and the best outcome for the customer and the team.
6. Hands-on familiarity with a modern toolchain, which may include: Cloudflare, HAProxy, Go, TypeScript, Datadog, Terraform, Docker, Kubernetes, or Nvidia hardware.

Bonus Points For

1. Experience with telephony systems (SIP, VOIP, WebRTC).
2. A background in ML infrastructure, model serving, or GPU computing.
3. Experience with real-time audio/video processing.

Benefits & Perks

1. Comprehensive healthcare, dental, and vision insurance.
2. Meaningful equity stake in a fast-growing company.
3. Every tool and resource you need to be successful.
4. A beautiful office in Jackson Square, SF, with stunning rooftop views.

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