Senior Software Engineer, Full Stack

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

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, Alt Capital, and other leading investors, we have scaled to $60M ARR with a team of 40 people, up from $5M at the start of 2025.

Our vision for 2026 is to build a modern CX platform where entire contact centers are powered by AI. Instead of basic automation that needs constant human tuning, we’re creating intelligent AI “workers” that can act as frontline agents, QA analysts, and managers — continuously executing, monitoring, and improving customer interactions.

We’re growing quickly and looking for ambitious builders who want to tackle hard technical problems, move fast, and have real impact at one of the fastest-growing voice AI startups.

Let’s build the future together.

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

• #4 on Brex's Fast-Growing Software Vendors of 2025: https://www.brex.com/journal/brex-benchmark-december-2025

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

• Enterprise tech 30: https://www.wing.vc/et30/overview

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: 200k - 300k

• Equity: Offers Meaningful Equity

• Location: Redwood City, CA, US (100% Relocation Provided)

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

2. Technical 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.)

3. 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. Existing codebase