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Sr Founding Backend Engineer

San Francisco, USAPosted 8 months ago
Full-timeremote

Job Description

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
  1. Online coding assessment (25-30 min)
  2. Technical phone interviews (2 rounds focusing on data structures and algorithms)
  3. Onsite/virtual interviews: practical coding, system design, and automation

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