Staff Engineer, Platform & Systems

About the role

Retell AI is using first-principles thinking to reimagine the call center with cutting-edge voice AI. Thousands of companies now use Retell's AI voice agents to handle sales, support, and logistics calls that once required large teams of human agents. Backed by Y Combinator, Alt Capital, and other leading investors, we've scaled to $80M in ARR with a team of 50, up from $5M at the start of 2025, and are now valued at over $1.5B. Our vision for 2026 is to build a modern CX platform where entire contact centers are powered by AI. Instead of basic automation that needs constant human tuning, we're creating intelligent AI "workers" that act as frontline agents, QA analysts, and managers, continuously executing, monitoring, and improving every customer interaction. We're growing fast and looking for ambitious builders who want to tackle hard technical problems, move quickly, and have a real impact on one of the fastest-growing voice AI companies in the world. You will own the technical direction of our core platform and systems, operating at a staff level to solve high-stakes infrastructure challenges. This role involves defining problems, designing solutions, and shipping production-grade systems that directly power our AI voice agents. You will partner with product and leadership to turn business requirements into scalable technical strategies while raising the bar for code quality and reliability. The ideal candidate thrives in ambiguity and drives end-to-end execution across distributed systems and product surfaces.

Key facts

What you'll do

Define and evolve the core platform and systems architecture that powers Retell's voice AI agents at scale.

Lead complex technical initiatives end-to-end, from discovery and design through implementation and production operation.

Make high-leverage technical decisions that balance speed, reliability, and scalability under real business constraints.

Raise the technical bar through design reviews, mentoring engineers, and hands-on contribution to critical systems.

Partner closely with product and leadership to translate ambiguous business needs into robust, executable technical roadmaps.

Identify and resolve performance, scalability, and reliability bottlenecks across the voice AI platform and infrastructure.

Own critical production systems, ensuring observability, resilience, and maintainability for customer-facing workflows.

Define and drive the adoption of engineering best practices as the platform scales and the team grows rapidly.

Evaluate and integrate new infrastructure technologies that unlock faster iteration and more capable AI worker behaviors.

Collaborate with SRE and platform teams to automate operations, reduce toil, and improve developer ergonomics.

Champion security and compliance considerations in the design of core platform components and APIs.

Work hands-on with code, diving into debugging, performance profiling, and complex system investigations when needed.

Influence hiring and technical direction by setting standards for platform thinking across engineering and product teams.

Serve as a go-to expert for difficult problems, unblocking teams and enabling them to ship with confidence.

Contribute to open-source or public-facing tools where appropriate to amplify Retell's technology leadership in voice AI.

Requirements

9+ years of experience building and operating production systems in a professional software engineering role.

Operated at a Staff or Principal level (or equivalent scope and impact) even if the official title was not present.

Strong ability to reason about systems design and clearly articulate tradeoffs between reliability, scalability, and delivery speed.

Deep comfort with owning ambiguous, complex problems and defining the path forward without a single spec.

A track record of building or scaling platforms that serve real customers at meaningful volume and uptime.

Exceptional judgment in making high-leverage technical decisions that balance innovation with operational stability.

Experience working quickly while maintaining rigor around correctness, reliability, and maintainability.

Hands-on proficiency with core infrastructure technologies relevant to distributed systems, APIs, and real-time processing.

Nice to have

Prior experience with Voice AI, real-time systems, or developer-facing platforms.

Deep background in distributed systems, APIs at scale, or infra/platform engineering.

Experience working directly with enterprise customers in high-stakes, regulated environments.

Practical notes

US Visas: Retell AI is open to sponsoring work authorization for qualified candidates, including H-1B, TN, L-1, E-3, F-1 (OPT/CPT), and O-1 visas.

Location: This role is based in Redwood City, California, with 100% relocation provided for eligible candidates.

Work authorization requirements and visa sponsorship details apply to roles based in the United States.