You will be a backend-leaning product engineer owning significant parts of River’s AI sales rep. You’ll build LLM-powered conversation logic and real-time voice infrastructure using Node, Next.js, and Postgres. This is a high-ownership IC role where you’ll solve ambiguous problems and ship production-ready software directly to users without middle management.
Full-Stack Product Engineer at River
River is building an AI account executive that joins live calls to demo, handle objections, and close deals for B2B companies. As a backend-leaning Full-Stack Product Engineer, you will own critical conversation logic and real-time voice infrastructure from the ground floor. If you're a high-ownership builder with LLM experience ready to ship fast in NYC, this is your chance to join a lean, elite team and shape the future of sales. We are offering $150k-$190k plus equity for engineers who have shipped real software and want to solve the hardest problems in voice AI.
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Location
New York, United States
Compensation
$150k-$190k + Equity
Company
River
Role overview
AI Sales
River builds AI voice agents that sell. Backed the founders of Ramp and Kalshi.
What you will do
- Architect and implement LLM-powered conversation logic and real-time voice infrastructure to ensure reliable, low-latency AI interactions during live calls.
- Own the end-to-end development of backend systems using Node.js, Next.js, and Postgres to support high-scale, production-ready sales automation.
- Collaborate directly on product strategy, identifying user needs and translating them into shipped features without the friction of detailed specs or project managers.
Who this is a fit for
- Proven experience shipping real-world software to production using TypeScript/JavaScript, Node.js, and modern databases like Postgres and Redis.
- Deep curiosity and hands-on experience building applications with LLM APIs, complemented by a strong interest in voice AI or WebRTC technologies.
- A “builder” mindset evidenced by a tier-1 pedigree, successful side projects with traction, or experience at high-growth engineering organizations like Ramp or Palantir.
Why this role is remarkable
- Build the future of sales by developing an AI AE capable of handling live, real-time objections and closing deals autonomously.
- Join an elite, early-stage team where you have direct influence on product direction and company culture from the ground floor.
- Work in a high-density, in-person environment in NYC designed for rapid shipping and solving complex engineering challenges like WebRTC and LLM orchestration.
How Jack & Jill work together
I get to know what you’re great at, then find roles you’d never find yourself.Ok, I'll go first. I'm Jack, an AI that gets to know you on a quick call, learning what you're great at and what you want from your career. Then I help you land your dream job by finding unmissable opportunities as they come up, supporting you with applications, interview prep, and moral support.
I recruit from Jack’s network and make the intro when I spot a great match.And I'm Jill, an AI Recruiter who talks to companies to understand who they're looking to hire. Then I recruit from Jack's network, making an introduction when I spot an excellent candidate.
Jack gets to know what you're great at and what you want next, then searches 15 million jobs daily and helps you discover roles at companies like this.
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If your profile’s a match and River wants to meet, Jill will make the intro. In the meantime, Jack will send you excellent alternatives.