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# Founding Engineer

- **Company:** River Partners
- **Location:** West New York, NJ, United States
- **Experience:** Expert
- **Salary:** $170,000.0 - $220,000.0
- **Contract:** Permanent contract
- **Skills:** Artificial Intelligence, Computer Literacy, PostgreSQL, Node.Js, Redis, Next.js, Data Streaming, TypeScript, WebSocket, WebRTC, Core Voice Platform, Large Language Models, Backend, Playwright
- **Published:** October 8, 2026
- **Apply:** https://www.disabledperson.com/jobs/75914595-founding-engineer

## About the Role

* 5+ years building and running production backend systems. You've been the person responsible when things break
 * Strong infrastructure skills: deploys, observability, scaling on a major cloud
 * Real-time or streaming experience (WebRTC, voice, video, websockets), or comparable low-latency work
 * Comfortable in TypeScript and Node (we use Next.js, Postgres, Redis)
 * Senior, high-ownership mindset. You're fine with ambiguity and you don't wait for a spec
 * Real product opinions. You care about what we build, not just how, and you'll tell us when you think we're wrong

Nice to have

 * Experience at a strong, recently founded company (last ~10 years) with a high engineering bar, ideally a startup you joined early or founded
 * LiveKit or similar real-time media stacks (WebRTC media servers, Pipecat)
 * Voice AI, avatars, or media pipelines
 * Browser use / computer use, LLM agents, Playwright or CDP, evals
 * Go-to-market / sales-tech tooling or exposure to the sales workflow

## Description

River builds AI voice agents for B2B SaaS sales teams. Our agent talks with prospects in real time: it qualifies them, answers the hard questions, demos the product by actually using it in a browser while it speaks, and follows up until the deal closes. A full AI seller, available 24/7.

We just closed a $2M pre-seed, backed by the founders of companies like Ramp, Kalshi, and JumpCloud. We turned on revenue recently and demand already outpaces what we can serve. This is our founders' second company - they built and sold the first.

About the role

Every River conversation runs on a sub-second loop: speech, a rendered avatar, several LLMs, and an agent using a real browser, all live in front of our customers' buyers. Your job is to make that loop fast and rock-solid. Backend and infrastructure are your priority, but you'll build across the whole product with us.

This is a founding role: you're a core member of the team, shaping what River becomes, not just keeping it running. Many decisions will be yours to own.

What you'll do

 * Own the live-call pipeline: real-time voice, avatar, and browser streaming in one sub-second loop
 * Own the infrastructure behind it: deploys, scaling, observability, cost
 * Push our browser-use agent forward. River demos real products by controlling a browser live, clicking and navigating complex apps while it talks, and making that reliable is one of the most interesting problems here
 * Put the engineering foundations in place as the team grows: monitoring, incident response, testing, evals
 * Ship product features across the stack, and talk to customers