Senior Software Engineer, Full Stack

ABOUT RETELL AI

Retell AI is using first-principles thinking to reimagine the call center with cutting-edge voice AI. Thousands of companies now use 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've scaled to $80M in ARR with a team of 50, up from $5M at the start of 2025, and are now valued at over $1.5B.

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 act as frontline agents, QA analysts, and managers, continuously executing, monitoring, and improving every customer interaction.

We're growing fast and looking for ambitious builders who want to tackle hard technical problems, move quickly, and have a real impact on one of the fastest-growing voice AI companies in the world.

Let's build the future together.

Recent recognition:

• No. 1 Best Places to Work in the Bay Area, San Francisco Business Times 2026 https://finance.yahoo.com/technology/ai/articles/voice-ai-startup-retell-ai-145200025.html

• Top 50 AI Apps, a16z (2025) https://a16z.com/the-ai-application-spending-report-where-startup-dollars-really-go/

• #3 Fastest-Growing Software Company, G2 Best Software Awards 2026 https://company.g2.com/news/g2s-2026-best-software-awards

• Best Agentic AI Software, G2 Best Software Awards 2026 https://www.retellai.com/blog/retell-ai-recognized-as-the-best-agentic-ai-software-by-g2

• #4 Fastest-Growing Software Vendor, Brex Benchmark 2025 https://www.brex.com/journal/brex-benchmark-december-2025

• Enterprise Tech 30 Class of 2026, Nasdaq & Wing VC https://www.nasdaq.com/videos/retell-ai

• Top-Ranked Startup, Lean AI Leaderboard https://leanaileaderboard.com/

• Backed by Y Combinator https://www.ycombinator.com/companies/retell-ai

ABOUT THE ROLE

Retell AI transforms customer experience with voice AI for enterprises, including customers like CVS/Aetna, American Airlines, Lenovo, and Grab. We have more customer stories than we can tell!

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.

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

• 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

• 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.

OTHER BENEFITS

• 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

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 exceptional builders.

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

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

INTERVIEW PROCESS

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 (60 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. Technical Interview (45 min): A system design-focused interview assesses your knowledge of building product-ready systems.

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

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

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

7. Existing codebase