Job Details

Founding Senior Software Engineer – Full Stack

Full-Time | San Francisco | In-Person

We've partnered with the founder of a fast‑scaling voice AI startup to help hire a Founding Senior Engineer to own core product and infrastructure and shape engineering culture from day one.

This company is building the “Retool for Voice” — a developer platform that makes it simple to build and deploy voice interfaces across SaaS, logistics, telehealth, and more. With Apple and Google introducing human‑like voice assistants to billions of users, this team is building the missing layer between raw LLMs and production‑ready voice apps. They launched in March, have grown revenue quickly, and already serve paying customers.

It's a ground‑floor opportunity to build foundational full‑stack systems in a real‑time, low‑latency environment—working directly with founders and early users, and playing a lead role in setting product and engineering direction.

What You'll Do

• Own end-to-end feature development—from customer request to production
• Build modular, API‑first systems that integrate real‑time voice capabilities
• Improve latency, reliability, and UX in critical product flows
• Contribute across the stack—from backend infra to frontend UX
• Help define technical architecture and build the culture you want to work in
• Build modular backend infra optimized for real‑time performance

You Might Be a Fit If You…

• Have 5+ years of full‑stack or backend experience, including owning systems end‑to‑end
• Are strong in React + TypeScript and comfortable jumping between frontend and backend
• Have startup experience or thrive in 0→1 environments
• Have operated at a Senior, Staff, or Principal level— even if the title didn't say it
• Want to work in‑person with a sharp, ambitious team in SF

What They're Looking For

• Clear communicator — You explain tradeoffs and decisions crisply
• Founder‑level drive — You take ownership without waiting for permission
• Execution bias — You ship quickly and iterate with users in mind
• Mission‑aligned — You believe voice‑first interfaces are the next wave of computing

Benefits

• Medical insurance

Seniority Level

Mid‑Senior level

Employment Type

Full-time

Job Function

Engineering and Information Technology

Industries

Software Development