Founding Senior Software Engineer (Full-stack) Join to apply for the Founding Senior Software Engineer (Full-stack) role at Retell AI Founding Senior Software Engineer (Full-stack) 4 weeks ago Be among the first 25 applicants Join to apply for the Founding Senior Software Engineer (Full-stack) role at Retell AI This range is provided by Retell AI. Your actual pay will be based on your skills and experience — talk with your recruiter to learn more. Base pay range $215,000.00/yr - $290,000.00/yr About Retell AI

At Retell AI, we're not just automating calls—we’re transforming how the world communicates. Our AI voice agents are reshaping sales, support, and customer engagement for leading brands. Backed by Alt Capital, Y Combinator, and top-tier investors, we've raised $4.7M in seed funding and hit $14M ARR with just 12 people.

We’re one of the fastest-growing Voice AI startups and we're on a mission to become the standard for voice automation at scale. We're also one of the top ranking startups at https://leanaileaderboard.com/.

About The Role

As a Founding Senior Full-Stack Engineer, you’ll shape the heart of Retell AI’s voice automation platform, building scalable systems and intuitive interfaces that power millions of AI-driven conversations. You’ll work across the stack—leveraging React, TypeScript, and Node.js—to deliver fast, beautiful, and reliable solutions. Collaborating closely with the founding team, you’ll bridge backend architecture (like prompt orchestration and telephony integrations) with frontend experiences (such as dashboards and analytics tools), ensuring seamless customer onboarding and impactful user experiences. This high-impact role offers rapid feedback loops, customer collaboration, and the opportunity to define a category-leading product that transforms global communication.

Key Responsibilities

Develop core features like prompt orchestration, dashboards, analytics, and telephony integrations. Build scalable full-stack systems, from polished UIs to robust APIs and DevOps workflows. Lead projects from architecture to production, owning coding, deployment, and iteration. Create intuitive interfaces and APIs, enabling customers to activate in hours. Support customer onboarding, debug issues, and turn feedback into product enhancements.

You Might Thrive If You

Have 2+ years of full-stack experience with React, TypeScript, Node.js, or Python. Hold a degree in CS, CE, or equivalent practical experience. Take ownership like a founder, proactively solving problems across the stack. Thrive in fast-paced settings, quickly adapting to new tools and challenges. Communicate clearly, collaborating effectively in small, dynamic teams.

Job Details

Job Type: Full-time, 70 hr/week (50 hr/week onsite with flexible hours + 20 hr/week work from home) Cash: 215k - 290k Equity: 0.4 - 0.6% Location: Redwood City, CA, US US Visas: Sponsors Visa & Green Card

Other Benefits

100% medical, dental, vision insurance coverage Unlimited breakfast, lunch, dinner, and snacks Gym and daily commute fee reimbursement Internet and phone bill covered

Compensation Philosophy

Best Offer Upfront: Choose from three cash-equity balance options, no negotiation needed. Top 1% Talent: Above-market pay (top 5 percentile) to attract high performers. High Ownership: Small teams, >$1M revenue/employee, and significant equity. Performance-Based: Offers tied to interview performance, not experience or past salaries.

Interview Process

Online Assessment (25–30 min): One HackerRank coding questions on practical problem-solving (7 days to complete). Technical Phone Interview 1 (30 min): Live coding on CoderPad, focusing on data structures and algorithms. Technical Phone Interview 2 (30–45 min): Full-stack development with JavaScript, TypeScript, React, and Node.js in a local environment. Onsite/Virtual Interviews (2-3 hrs): Hosted in our office if located in the Bay Area or virtual, with three rounds: Practical Coding: Tackle real-world coding tasks with debugging in a local environment. System Design: Architect a production-ready system. Tools & Automation: Build automations or improve workflows in any basic environment setup like Python, Java, Node.js, etc.

Learn More

Retell AI - API That Turns Your LLM Into A Human-Like Voice Agent

Retell AI Basics: Everything You Need to Start Building Voice Agents

Join Retell AI to shape the future of voice automation, building scalable, impactful full-stack systems that redefine AI-driven communication.

Compensation Range: $215K - $290K

Seniority level Seniority level Mid-Senior level Employment type Employment type Full-time Job function Job function Engineering and Information Technology Industries Technology, Information and Internet Referrals increase your chances of interviewing at Retell AI by 2x Get notified about new Senior Software Engineer jobs in Redwood City, CA . Palo Alto, CA $160,000.00-$180,000.00 21 hours ago San Francisco, CA $160,000.00-$180,000.00 21 hours ago Mountain View, CA $145,000.00-$170,000.00 1 week ago Mountain View, CA $138,225.00-$207,575.00 1 week ago Software Engineer, AI Platform - New Grad Mountain View, CA $145,000.00-$170,000.00 1 week ago Mountain View, CA $141,000.00-$202,000.00 6 days ago Mountain View, CA $141,000.00-$202,000.00 1 week ago San Francisco, CA $40.00-$45.00 2 hours ago Software Engineer (L4), Content & Business Products Software Engineer, Machine Learning (Multiple Levels) - Slack San Francisco, CA $167,300.00-$334,600.00 13 hours ago San Jose, CA $100,500.00-$173,250.00 1 day ago Mountain View, CA $130,000.00-$176,000.00 1 week ago Sunnyvale, CA $167,000.00-$185,500.00 3 days ago San Francisco Bay Area $160,000.00-$180,000.00 22 hours ago (General Hire) Software Engineer Graduate (Advertisement Team) - 2025 Start (BS/MS) San Jose, CA $113,500.00-$250,000.00 2 weeks ago San Francisco, CA $60,000.00-$80,000.00 2 days ago San Francisco, CA $130,000.00-$240,000.00 20 hours ago San Francisco, CA $99,500.00-$200,000.00 2 weeks ago San Jose, CA $113,400.00-$206,300.00 1 week ago San Francisco, CA $130,000.00-$250,000.00 5 days ago Palo Alto, CA $107,000.00-$145,400.00 22 hours ago Software Engineer, Google Store, Front End Mountain View, CA $141,000.00-$202,000.00 3 days ago San Francisco, CA $99,840.00-$133,320.00 2 days ago We’re unlocking community knowledge in a new way. Experts add insights directly into each article, started with the help of AI.

#J-18808-Ljbffr