Sr Founding Backend Engineer
Posted Updated
Senior Backend Engineer | Voice AI Startup
About the Company
Our client is a fast-growing Y Combinator-backed Voice AI startup transforming sales, support, and customer engagement. With $5M in seed funding and approaching $30M ARR already, achieved with just 20 people, they're building the standard for voice automation at scale.
The Role
As a Founding Senior Backend Engineer, you'll build the core systems powering millions of AI-driven conversations. You'll work on real-time audio, global telephony, and developer tooling, collaborating directly with the founding team to define a category-leading product.
Key Responsibilities
- Build foundational architecture including prompt orchestration, testing frameworks, observability dashboards, and telephony integrations
- Design scalable backend systems and DevOps workflows for reliable performance across millions of calls
- Lead complex projects from architecture to production, owning delivery and monitoring
- Collaborate with product and design teams to create intuitive APIs for rapid customer onboarding
- Support customer onboarding, troubleshoot issues, and translate feedback into product improvements
Requirements
- 2+ years backend development experience
- CS, CE, or EE degree or equivalent practical experience
- Ownership mindset with passion for impactful software
- Thrives in fast-paced, ambiguous environments with strong problem-solving skills
- Clear communication and cross-functional collaboration abilities
- Bonus: Startup experience and cloud infrastructure/DevOps knowledge
Compensation & Benefits
- Salary: $200K - $280K
- Equity: 0.25% - 0.45%
- Schedule: Full-time, 70 hrs/week (50 onsite + 20 remote, flexible hours)
- Location: Redwood City, CA
- 100% medical, dental, vision coverage
- Unlimited meals and snacks
- Gym and commute reimbursement
- Visa sponsorship available (H1B, TN, L-1, E-3, F-1, O-1)
Interview Process
- Online coding assessment (25-30 min)
- Technical phone interviews (2 rounds focusing on data structures and algorithms)
- Onsite/virtual interviews: practical coding, system design, and automation