Founding Senior Software Engineer (Frontend)

ABOUT RETELL AI

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We believe voice is still the most natural way humans communicate, yet it has been trapped in outdated call centers for decades.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/

ABOUT THE ROLE

As a Founding Senior Frontend Engineer, you’ll shape the user experience of our AI voice platform, building intuitive interfaces and tools that power millions of automated conversations. You’ll work across the stack, focusing on React and TypeScript, and collaborate with the founding team to deliver fast, beautiful, and scalable solutions.

KEY RESPONSIBILITIES

• Design and build core UI features like prompt management, dashboards, and analytics tools.

• Develop responsive, intuitive interfaces using React, TypeScript, HTML, CSS, and JavaScript.

• Collaborate on backend APIs and DevOps to ensure seamless, scalable systems.

• Lead frontend projects from concept to launch, owning architecture, coding, and iteration.

• Work with customers to onboard, debug, and turn feedback into UX improvements.

YOU MIGHT THRIVE IF

• Have 2+ years of experience building production-grade apps with React and TypeScript.

• Hold a degree in CS, CE, or equivalent practical experience.

• Take ownership like a founder, proactively solving problems with clean design thinking.

• Thrive in fast-paced environments, quickly learning new tools and frameworks.

• Collaborate effectively, balancing clarity and momentum 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: 0.25 - 0.45%

• Location: Redwood City, CA, US

• US Visas: Retell AI is open to sponsoring work authorization for qualified candidates, including 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. Online Assessment (25–30 min): 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. Tec