Staff Engineer, Platform & Systems

Principal/Staff EngineerRetell AI is using the first principles to reimagine the call center with cutting edge voice AI. Since launching 18 months ago, thousands of companies now utilize 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 have scaled to $36M ARR with a team of 20 people, up from $5M at the start of 2025. 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 can act as frontline agents, QA analysts, and managers — continuously executing, monitoring, and improving customer interactions. We're growing quickly and looking for ambitious builders who want to tackle hard technical problems, move fast, and have real impact at one of the fastest-growing voice AI startups. Let's build the future together.Key ResponsibilitiesOwn the design and evolution of core platform and systems architecture.Lead complex technical initiatives end-to-end, from concept to production.Make high-leverage technical decisions that balance speed, reliability, and scale.Raise the technical bar through design reviews, mentoring, and hands-on leadership.Partner closely with product to translate business needs into robust technical solutions.Identify and resolve performance, scalability, and reliability bottlenecks.Help define engineering best practices as we scale the team and platform.You Might Thrive IfYou have 9+ years of experience building and operating production systems.You've operated at Staff or Principal level (or equivalent scope), even if the title wasn't official.You're strong in systems design and can reason clearly about tradeoffs.You move fast but care deeply about correctness, reliability, and maintainability.You're comfortable owning ambiguous problems and defining the path forward.You've built or scaled platforms used by real customers at meaningful volume.You enjoy being hands-on — writing code, reviewing designs, and unblocking teams.Bonus points if you've worked with: distributed systems, Voice AI, real-time systems, APIs at scale, infra/platform work, or developer-facing products.Why This RoleReal ownership over core systems.Direct influence on product and company direction.A small, high-caliber team with very little process drag.Problems that matter — to customers, revenue, and scale.If you want a role where your decisions visibly shape the company, this is it.Job DetailsCash: $240-$300kEquity: Offers EquityLocation: Redwood City, CA, USUS 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.Other Benefits100% coverage: for medical, dental, and vision insurance$70/day DoorDash credit: for unlimited breakfast, lunch, dinner, and snacks$200/month: wellness reimbursement (gym, fitness classes, etc.)$300/month: commuter reimbursement (gas, Caltrain, etc.)$75/month: phone bill reimbursement$50/month: internet reimbursementCompensation PhilosophyBest Offer Upfront: Choose from three cash-equity balance options; no negotiation needed.Top 1% Talent: Above-market pay (top 5 percentile) to attract exceptional builders.High Ownership: Small teams, >$1M revenue/employee, and significant equity.Performance-Based: Offers tied to interview performance, not experience or past salaries.Interview ProcessRecruiter Screen (15min): Speak with a member of the talent team to learn more about us and which team you would be a good fit for.Technical Interview (45 min): Practical coding session focused on code fluency and system design (For frontend roles, we will focus on React-specific questions. For backend roles, we take a technology-agnostic approach.)Technical Interview (45 min): This is a systems design-focused interview. There will be no coding; we want to assess your skills in systems design.Onsite/Virtual Interviews (2–3 hrs): Hosted in our office if located in the Bay Area or virtual, with three rounds: