Fullstack Engineer - AI Infra & Enterprise Backend

Scion Staffing, Inc.; San Francisco (CA); On-site; USD 160,000 - 180,000; Full time

Benefits offered by this job

Own products end-to-end with meaning

Work with enterprise customers

Grow with experienced engineers

Job summary

Scion Staffing, Inc. is representing an AI infrastructure startup in San Francisco seeking a backend-oriented full-stack engineer to own features end-to-end and help scale enterprise-grade infrastructure powering AI-driven applications.

In this role you will design and own complex, multi-tenant backend systems, build reliable external integrations, and ensure services are scalable, observable, and resilient in production.

Qualifications

• 3–6+ years building and operating production software.
• Strong backend skills with the ability to ship across the full stack.
• Production TypeScript and Node.js or Bun.

Responsibilities

• Build the backend systems powering the agent-evaluation and continuous-improvement platform.
• Improve the data models behind evaluation datasets, experiment runs, agent traces, knowledge versions, findings, and customer-defined quality criteria.
• Own enterprise integrations across their full lifecycle: auth, OAuth, webhooks, incremental syncs, backfills, rate limits, schema changes, retries, monitoring, and production support.
• Own features from technical design and implementation through deployment, monitoring, customer feedback, and iteration.
• Work directly with customers when needed — understand their systems, diagnose failures, and turn one-off requirements into reusable product capabilities.

Skills

Backend development

Node.js/TypeScript

PostgreSQL

Observability

Distributed systems

Tools

Redis

OAuth

Webhooks

Job queues

Job description

Scion Staffing, Inc. is representing an AI infrastructure startup in San Francisco seeking a backend-oriented full-stack engineer to own features end-to-end and help scale enterprise-grade infrastructure powering AI-driven applications.

In this role you will design and own complex, multi-tenant backend systems, build reliable external integrations, and ensure services are scalable, observable, and resilient in production.