Senior Founding Engineer

Job description: JOB DESCRIPTIONThis company handles millions of calls per month and needs an engineer who has worked at that scale before and knows how to build systems that don't break under it. This is an architecture-heavy, full-stack role not just backend. You will own everything from database optimization to reducing dashboard load times from four seconds to sub-100 milliseconds.You will work on-site directly with the founding team, contributing across architecture, infrastructure, and product. This is a high-ownership role suited for someone who moves fast, brings strong engineering discipline, and has personally mastered a skill outside of work to an elite level.Key Responsibilities:Architect and develop systems that simulate, analyze, and evaluate conversational AI agents across voice and multimodal formatsDesign resilient, scalable infrastructure using AWS (Lambda, EC2, WebSockets, SIP) to support millions of real-time conversationsIdentify and reduce system bottlenecks across the full stack from database query optimization to frontend dashboard performanceDevelop algorithms and pipelines that surface insights, detect failure modes, and ensure agents operate safely and reliablyEstablish and enforce strong engineering practices across code review, architecture design, and system designWork on-site with customers to build, sell, and deploy the product in real-world environmentsVisa Sponsorship H-1B are okay Qualifications: REQUIREMENTSTypeScript, Python, SQL, AWS non-negotiable core stack proficiencySystems and architecture design at scale ability to design, articulate, and defend decisions for high-volume production environmentsFull-stack engineering across React, Next.js, and FastAPIVoice AI stack experience familiarity with tools such as LiveKit, Deepgram, Cartesia, or ElevenLabsExtreme hobby or competitive achievement outside of work requiring hundreds of hours of deliberate practice (deal-breaker if absent) Why is This a Great Opportunity: WHY THIS IS A GREAT OPPORTUNITYSeed-stage AI company backed by Y Combinator, Floodgate, and PeakXV high-growth trajectory with strong institutional supportCrossed $1M in revenue with doubling growth every three months since launch clear product-market fit already establishedClient roster includes Fortune 500 names and fast-scaling tech companies massive market visibility for a founding engineerFirst-of-its-kind QA platform for conversational AI this is a category-defining role in a rapidly expanding spaceFounding engineer title with direct access to and collaboration with the CEO and founding teamHigh-ownership technical role: you define architecture, set engineering standards, and shape the product from the ground upPerks include health insurance, gym membership (5+ visits/month), and $500 desk/workspace stipendBenefits & PerksHealth insuranceHealth insuranceGym membership comped if you go 5+ times per month$500 desk and workspace setup stipendEquity 0.2% - 1%Salary Type : Annual SalarySalary Min : $ 200000Salary Max : $ 250000Currency Type : USDNigel