Senior Software Engineer - Full Stack

Retell AI is using the first principles to reimagine the call center with cutting edge voice AI.

We believe voice is still the most natural way humans communicate, yet it has been trapped in outdated call centers for decades. Our mission is to bring intelligence, empathy, and speed to every phone conversation between businesses and their customers.

Since launching 18 months ago, thousands of companies now utilize Retell’s AI voice agents to handle sales, support, and logistics calls that once required large teams of human agents. Backed by Y Combinator, Altman Capital, and other leading investors, we have scaled to $30M ARR with a team of 20 people, up from $5M at the start of 2025.

Now, we’re scaling fast, and we’re looking for bold, ambitious people to help us build the gold standard for voice automation. If you want to work on deeply technical challenges, move fast, and make an outsized impact at one of the fastest-growing Voice AI startups in the world, you’ll love it here.

Let’s build the future of voice automation together.

• We’re a top 50 AI app in a16z list: https://tinyurl.com/5853dt2x

• We're also one of the top ranking startups on: https://leanaileaderboard.com/

• Build the Dream Team: We hire high performers who work onsite in the San Francisco Bay Area, move fast, and collaborate deeply. Feedback is open, direct, and constant.

• Customer obsession. We start with the customer and work backwards. Every job and task matters only if it ultimately benefits the customer.

• Insist on the Highest Standards: We ship products you’re proud to show everyone — even if it means spending more time perfecting them.

We like to keep it real, we move fast, build fast, and change fast. That’s part of the fun for us, but we know it’s not for everyone.

As a 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.

• 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.

• 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.

• Cash: 215k - 290k

• Equity: 0.25 - 0.45%

• Location: Redwood City, CA, US

• US Visas: Retell AI is open to sponsoring work authorization for qualified candidates, including H1B/H-1B, TN, L-1, E-3, F-1 (OPT/CPT), and O-1 visas.

• 100% coverage for medical, dental, and vision insurance

• $70/day DoorDash credit for unlimited breakfast, lunch, dinner, and snacks

• $200/month wellness reimbursement (gym, fitness classes, etc.)

• $300/month commuter reimbursement (gas, Caltrain, etc.)

• $75/month phone bill reimbursement

• $50/month internet reimbursement

• Best Offer Upfront: Choose from three cash-equity balance options; no negotiation needed.

• Top 1% Talent: Above-market pay (top 5 percentile) to attract exceptional builders.

• High Ownership: Small teams, >$1M revenue/employee, and significant equity.

• Performance-Based: Offers tied to interview performance, not experience or past salaries.

1. Online Assessment (1.5 Hours): Coding questions on practical problem-solving (7 days to complete).

2. Intro Call (15-20min): Connect with our Founding Recruiter to get a deeper look at the team and the work you'd be doing.

3. Technical Phone Interview (45 min): Practical coding session focused on code fluency and system design (For frontend roles, we will focus on React-specific questions. For backend roles, we take a technology-agnostic approach.)

4. Technical Interview (45 min): A deep dive into your backend chops and how you think through systems design.

5. Onsite/Virtual Interviews (2–3 hrs): Hosted in our office if located in the Bay Area or virtual, with three rounds:

   1. Practical Coding: Tackle real-world coding tasks with debugging.

   2. System Design: Architect a production-ready system.

   3. Tools & Automation: Build automations or improve workflows in any basic environment setup like python, java, node.js, etc.

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