Founding Backend Engineer at River

You will own the live-call pipeline for River’s voice AI agent, ensuring sub-second response times during live customer interactions. As a founding backend engineer, you will manage infrastructure, scale the data layer, and build reliable browser automation to demo products in real-time. This is a high-ownership role defining the engineering foundations of autonomous sales.

• Architect and maintain the live-call pipeline, ensuring low-latency stability and performance for voice AI agents during high-stakes sales conversations.
• Own the end-to-end infrastructure including deployments, scaling, observability, and incident response using technologies like Railway, Postgres, and Redis.
• Develop robust browser automation tools using Playwright and CDP to enable the AI to drive live product demos while speaking to prospects.

• Brings 5+ years of experience building production backend systems with a proven track record of personally owning reliability, on-call rotations, and incident response.
• Possesses deep expertise in real-time, streaming, or low-latency systems such as WebRTC, voice protocols, or high-throughput trading platforms.
• Is a senior-level generalist comfortable with TypeScript and Node who uses AI agents to multiply their output and can ship without a formal spec.

• Join a founding team backed by iconic fintech and trading founders from Ramp, Kalshi, and JumpCloud to solve the hardest latency problems in voice AI.
• Work on a product that is already generating revenue and seeing demand that outpaces capacity, moving beyond simple lead generation to autonomous sales closing.
• Solve deep technical challenges involving real-time WebRTC pipelines, browser-use automation, and LLM orchestration where every millisecond counts in front of live buyers.