backend product engineer

VAPI LLC
San Francisco, CA, United States
1 day ago
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Role details

Contract type
Permanent contract
Employment type
Full-time (> 32 hours)
Working hours
Regular working hours
Job source

Tech stack

Application Programming Interfaces (APIs) Artificial Intelligence Amazon Web Services Databases Data Systems PostgreSQL Node.Js TypeScript Management of Software Versions Speech Recognition Real Time Systems Large Language Models
+7 more
Backend Event Driven Architecture Kubernetes Apache Kafka Free and Open-Source Software Speech Synthesis Serverless Computing

Job description

  • More than 1 million developers have built 2.7M+ agents on Vapi. Every assistant depends on a growing product surface-from Composer, Simulations, Monitoring, and Knowledge Base to Versioning and Deployments.
  • Behind those experiences are hard backend product problems: durable APIs and data models, real-time and asynchronous workflows, observability, evaluations, guardrails, and reliable operation of non-deterministic systems.
  • We’re hiring a backend product engineer to own those systems end to end and help customers move voice agents from a compelling demo to dependable production-at Fortune 500 scale. The work is genuinely hard and unusually fun.

What You’ll Do:

  • 30 Days: Make real calls and build real assistants across LLM, speech-to-text, text-to-speech, and telephony integrations. Develop a working mental model of how Vapi’s product surfaces map to APIs, services, data systems, and production workflows, then ship your first scoped backend product improvement.
  • 60 Days: Own a meaningful backend area in agent self-improvement, trust, or guardrails. Take a customer problem from product spec to shipped system-designing the API, services, and data model; defining evaluation and rollout criteria; and instrumenting the result. Use AI coding agents thoughtfully as a throughput and quality lever.
  • 90 Days: Operate as an independent owner for a customer-facing backend area. Run the full improvement loop-authoring, evaluation, deployment, observation, and iteration-while improving reliability and developer experience. Be a core voice in product decisions and have multiple meaningful improvements in production., + Craft matters. We aim to build products and experiences customers genuinely love, not just tolerate.
  • Commit and follow through
  • We finish what we start and build trust by being people others can count on.
  • Why not today?
  • We value urgency and momentum. The fastest path to customer value usually wins.
  • Seek raw input
  • We go directly to customers, data, and teammates instead of relying on summaries or assumptions.
  • It’s our problem
  • We operate as one team. We share credit, own mistakes together, and support each other when things get hard.
  • Be direct and kind
  • We give feedback clearly, respectfully, and without delay.

Requirements

  • A track record operating at senior or staff scope: independently owning customer-facing backend product areas from an ambiguous problem through measurable production outcomes.
  • Strong hands-on experience with TypeScript/Node.js, Go, or a comparable backend stack, plus the ability to design clear APIs, services, and data models.
  • Experience building distributed or asynchronous systems with databases, queues, workflows, or event-driven patterns-and reasoning clearly about failure modes.
  • Strong product judgment: you start with the user problem, turn incomplete requirements into a clear technical approach, and make tradeoffs based on customer impact.
  • Production ownership: you care about testing, observability, reliability, incident response, safe rollouts, and what happens after launch.
  • Regular, thoughtful use of AI-assisted development tools to improve speed and quality, paired with strong engineering judgment about the result.
  • Self-direction, customer empathy, and clear communication. You stay hands-on, collaborate directly across functions, and remain accountable for outcomes.

Nice-to-haves

  • Experience with Postgres and high-volume, event-driven systems using queues or durable workflows such as BullMQ, Kafka, or Temporal.
  • Experience with real-time systems, voice or telephony, LLM-powered products, or AI agents.
  • Experience operating cloud-native services on AWS and Kubernetes/EKS.
  • Experience building developer platforms, public APIs, SDKs, or dashboards used by technical customers.
  • Experience at a fast-growing startup, building a zero-to-one product, or founding a company.
  • Open-source contributions, public technical writing, or other evidence of craft beyond your day job.

Benefits & conditions

  • Real stake: We offer a competitive salary and excellent equity ownership
  • Comprehensive health coverage: medical, dental, and vision plans
  • Team love: We love hanging out, and we do quarterly off-sites
  • Flexible time off: take what you need
  • More: catered meals, transportation, gym, equipment, and a $10k annual L&D budgetMore: catered meals, transportation, gym, and a $10k annual L&D budget.

About the company

Voice AI that resolves, not transfers.

Most phone systems trap callers in menus and scripts. Vapi is the platform for deploying voice agents that know your business and can listen, adapt, and resolve in minutes.

  • The numbers: 1 billion calls. 1 million developers. 10x enterprise ARR growth
  • The customers: Amazon Ring, ServiceTitan, New York Life, Intuit, Kavak, and thousands more, from YC startups to the Fortune 500
  • The news: a $50M Series B led by Peak XV Partners, with Bessemer Venture Partners, Kleiner Perkins, M12 (Microsoft’s Venture Fund), Y Combinator, and our earlier backers. Total raised: $72M

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