Founding Engineer

An AI startup in New York City is looking for a Founding Engineer to join their team.Compensation: $180K–$250K + EquityLocation: New York, NY; 5 days onsite per week US Citizen/GC Holders Only; No Visa SponsorshipWithin this role, you'll own a full product area from day one, from the first idea through production, with no PM between you and the customer. You'll get on customer calls, make product decisions yourself, and ship fast. As the company grows, you can move into leadership or stay deep on the IC track.Responsibilities:Build and ship full stack features in TypeScript (Node.js, React/Next.js)Build agent products directly on LLM APIs and agent SDKsWork on voice and SMS agents, long-running agent state and memory, and evals and guardrailsTalk to customers and turn what they need into product decisions without waiting for a roadmapQualifications:RequiredShipped a 0 to 1 product at a high-growth startup, as a founder, or on a new product team at a big tech companyStrong TypeScript (Node.js, React/Next.js)Comfortable making product calls on your own and talking to customers3 to 10 years of full stack engineering experienceDeep experience in at least one of these: production voice or SMS agents (Retell, Vapi, Ultravox, 11x-style), long-running agent state and memory, B2B2C or marketplace products, or agent evals and guardrailsHas built real products directly on LLM APIs or agent SDKs (Anthropic, OpenAI, Vercel AI SDK, Mastra or similar), not tutorials or thin wrappersPreferredFormer YC founder or a founder whose company got real traction (revenue, funding or an acquisition); If it failed, you can explain whyTop CS program, which matters most for candidates with 3 to 4 years of experiencePython for real-time voice pipelines (LiveKit, Deepgram, STT/TTS) or eval tooling (Braintrust, LLM-as-judge)