Senior Software Engineer, Full Stack

About the role

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.