Job Description

About Retell

Retell is building the new standard for automating call center communications, including sales, support, customer engagement, and retention calls.

Backed by Altman Capital, Y Combinator, and top investors, we've raised a $4.7M seed round and hit $10M ARR in 15 months.

Check us out on the Top Lean AI Native Companies Leaderboard at leanaileaderboard.com .

Why This Company

Twenty years ago, every business found itself needing a website, the new gateway to the world. Platforms like WordPress and Squarespace rose to become the standard for getting businesses online.

Today, we’re at the start of a new shift. Every business that relies on phone interactions can now have an AI voice agent of their dreams. A tireless and empathetic receptionist, salesperson, debt collector, or appointment reminder that works 24/7. Operational bottlenecks vanish overnight. Doubling your business no longer means doubling your team. Customer experience no longer suffers. (Ever tried calling an East Coast bank after 3 p.m. PT?) But companies aren't ready. Platforms don't exist.

At Retell, we're building the new standard for building AI voice agents. A seamless UI, a comprehensive toolkit, effortless integrations, and a thriving builder community, we're creating everything businesses need to deliver exceptional phone interactions on every single call.

This shift is happening, so why not be part of the team that defines it?

Video Walk Through About The Product

Why This Role

This is a high-impact role for engineers who want to move fast, take ownership, and help build a category-defining product from the earliest days. As a Founding Senior Software Engineer, you won’t just be shipping features—you’ll shape the core systems and experiences that power millions of automated conversations.

You’ll work across the stack, solving tough technical challenges in real-time audio, global telephony, and developer tooling. You’ll collaborate closely with the founding team, talk to customers, and ship improvements weekly—sometimes daily.

If you’re excited by big problems, fast feedback loops, and the opportunity to help define how businesses use voice AI at scale—this is the role for you.

Position : Founding Senior Software Engineer

Job type: Full-time 70hr/week (50 hr/week onsite with flexible hours + 20 hr/week work from home)

Salary: $200K - $310K

Equity: 0.25% - 0.85%

Bonus: $20k - $100k

Location: San Carlos, CA, US

US visas: Sponsors Visa & Greencard

Benefits: 100% medical, dental, vision insurance coverage. Unlimited breakfast, lunch, dinner, and snacks. Gym, daily commute fee reimbursement. Internet, phone bill covered.

Who You Are

• Builder at Heart – You’ve got 1+ years of backend development experience and a passion for shipping real, impactful software. You hold a degree in CS, CE, or EE—and you know how to get things done.
• Founder-Minded – You take ownership like it’s your name on the door. You care deeply about the work, think like a founder, and constantly look for ways to make the biggest impact.
• Fast-Moving & Curious – You thrive in ambiguity, love solving new problems, and aren’t afraid to roll up your sleeves in fast-paced environments.
• Clear Communicator & Team Player – You know how to speak up, collaborate across functions, and move forward even when not everyone agrees. You value clarity, momentum, and working with kind, driven people.
• Startup-Proven (or Ready to Be) – Experience in a startup is a bonus, but grit and adaptability matter more. Bonus points if you’ve worked with modern cloud infra and DevOps stacks.

What You’ll Do

• Build Core Features – Ship foundational tools for our AI voice platform—developing prompt orchestration systems, internal testing frameworks, real-time observability dashboards, analytics pipelines, and global telephony integration.
• Scale What Matters – Design and maintain scalable backend systems and DevOps workflows that ensure performance and reliability across millions of AI-powered phone calls worldwide.
• Own Complex Projects – Lead ambitious technical projects end-to-end—from architecture design and implementation to monitoring in production. You’ll scope the work, break it down, and drive delivery.
• Design for Users – Work cross-functionally with product managers, designers, and other engineers to create seamless, intuitive interfaces and APIs that help customers get up and running in hours, not weeks.
• Work With Customers – Jump in to support customer onboarding, troubleshoot complex issues in production, and turn real user feedback into meaningful product improvements that drive adoption.

Our Compensation Philosophy

Our Strongest Offer, Upfront

• We give you our best offer from the start. No need to negotiate or match other companies offer — instead, we offer three clear compensation options, each with a different balance of cash and equity. You pick what fits you best.

Designed for Talent Density

• We’re building with the top 1%, not the average. That’s why our compensation is set far above market — to attract people who raise the bar for everyone around them.

Scale Through Code, Not Headcount

• We aim for >$1M in revenue per employee. That means smaller teams, fewer layers, and higher ownership per person — both in terms of scope and equity.

Performance > Background

• We don’t anchor to other companies, past salaries, or industry ranges. Your offer is based entirely on your performance in our interview process. That’s it.

Experience Doesn’t Dictate Pay

• Your offer is based solely on how well you perform in the interview process. We don’t factor in past salaries, titles, or number of years worked. You can earn our highest tier with zero years of experience — if you prove you’re ready for it.

Interview Process

Online Assessment – We’ll kick things off with a short HackerRank assessment—two coding questions, 25–30 minutes total. You’ll have 7 days to complete and submit it.

Phone Interview 1 – A 30-minute live coding session focused on data structures and algorithms. We'll share a CoderPad link, and you’re free to use your preferred language.

Phone Interview 2 – A 30–45 minute technical interview, again using CoderPad, to dive deeper into your algorithmic thinking and coding fluency.

Onsite Interviews – These take 1–4 hours and are conducted in person in the San Francisco Bay Area. Please bring a computer for any hands-on portions. For remote candidates, we’re happy to arrange virtual sessions. There are up to four rounds:

• Practical Coding Session – Tackle real-world coding tasks, referencing documentation and debugging along the way.
• System Design Interview – Walk through the architecture of a production-ready system and share your high-level thinking.
• Tools & Automation Session – Build automations or use common developer tools to improve workflows.
• Behavioral Interview – A conversation about your past experience, decision-making, and work style.

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