Human Delta: Full Stack Engineer (Backend-Leaning)

San Francisco, CA · On-site · Full-time
Compensation: $120,000 - $200,000 + equity

About the Company

Our client is an early-stage, venture-backed startup building infrastructure for the agentic enterprise. Their platform helps large organizations keep the knowledge behind their AI agents accurate and conflict-free, closing the loop between how agents perform in production and the information they depend on, so reliability improves over time. They are already live with major enterprise customers and growing quickly on the back of rising demand.

Founded 2025 · Small founding-stage team · Industry: AI, Enterprise Software, B2B

The Role

This is a backend-leaning full-stack role (roughly a 90/10 backend-to-frontend split) building the systems behind the platform and its next generation of agent products. Most of the challenge lives in the backend: data modeling, queues, execution pipelines, integrations, observability, reliability, and debugging distributed workflows. You should also be comfortable taking a feature through the full stack and shipping the product surface that makes the underlying system useful. You will have real ownership over architecture and product decisions and work closely with a small, highly technical team and enterprise customers.

What you'll be doing

• Build the backend systems powering an agent evaluation and continuous-improvement platform.
• Shape the data models behind evaluation datasets, experiment runs, agent traces, knowledge versions, and customer-defined quality criteria.
• Own enterprise integrations end to end: authentication, OAuth, webhooks, incremental syncs, backfills, rate limits, schema changes, retries, monitoring, and production support.
• Own features from technical design through deployment, monitoring, customer feedback, and iteration.
• Work directly with customers to diagnose failures and turn one-off needs into reusable product capabilities.

Tech stack: Python, TypeScript, distributed systems, enterprise integrations; relational and vector databases.

Requirements

• 2-4 years of experience as a backend-leaning full-stack software engineer.
• A track record of building and running production systems used by enterprise customers.
• Professional, hands-on experience with TypeScript.
• Genuine full-stack comfort across both backend and frontend, with Python as the primary backend language.
• Experience at an early-stage startup (roughly under 50 people) with real, hands-on ownership.
• A bachelor's degree in Computer Science or a closely related field.
• Authorization to work in the US as a citizen, green card holder, or on OPT with several years of runway remaining. This role does not offer visa transfer or sponsorship.

Nice to Haves

• A background as a founder, or an active hackathon builder.
• Prior exposure to agent evaluation, LLMs, or evals/QA work.

Why Join

• Early engineering seat with meaningful equity and direct influence over core product architecture.
• Hard, high-impact backend problems: pipelines, integrations, observability, and reliability at real enterprise scale.
• Small, senior, fast-moving team working shoulder to shoulder with founders and early customers.

Details

• Location: San Francisco, CA
• Work policy: On-site, Monday to Friday; no required travel
• Compensation: $120,000 - $200,000 + equity
• Visa sponsorship: Not available (US citizen, green card, or OPT with multiple years remaining)
• Employment type: Full-time