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# Senior Software Engineer, Agents (Foundation Agents)

- **Company:** Fieldguide Inc.
- **Location:** San Francisco, CA, United States
- **Experience:** Expert
- **Contract:** Permanent contract
- **Skills:** Artificial Intelligence, Distributed Systems, Software Product Management, Backend, Build Management, AI Platforms, Front End Software Development
- **Published:** November 7, 2026
- **Apply:** https://www.juju.com/job/28_25303_b2455aa6f7725daca6169af7f1ffe9e1

## About the Role

* You think in evals and error analysis as a discipline; you dig into why an agent failed and fix the systemic cause
 * You're strong in the backend and comfortable owning platform-level systems
 * You're motivated by long-horizon agents that do real work in production
 * You multiply the people around you, not just your own output, * 1+ years working specifically on agents
 * Strong experience working on an AI platform
 * Demonstrated experience building evals and performing error analysis
 * Backend engineering experience, * Strong platform engineering skills
 * Frontend experience
 * Distributed systems experience

## Description

The Foundation Agents team stewards the long-horizon agents powering the Fieldguide AI platform. We work at the frontier of AI product development: agent knowledge, evaluations, and improving quality and reliability at scale. As a Senior Software Engineer, Agents, you'll take ownership of how the team measures and improves agent quality, and help drive the platform forward., * Evals strategy and error-analysis practice, shaping how the team measures and improves agent quality

 * Design and build agent knowledge and evaluation infrastructure for Fieldguide's long-horizon agents
 * Lead error analysis on agent behavior, turning findings into concrete platform-level reliability improvements
 * Build and harden backend systems that support agent execution, evaluation, and monitoring at scale
 * Drive the AI platform's reliability and quality roadmap forward, working closely with the broader AI team
 * Mentor engineers on the team, raising the bar on eval rigor and error-analysis practice, * Long-horizon agents: Working on agents that do real, sustained work
 * Evaluation as a craft: Evals and error analysis are core to how this team improves quality, not an afterthought
 * Platform-level impact: Your work shapes the reliability and quality of every agent built on top of it
 * Frontier problems: You're working on open problems in agent reliability that don't have established playbooks yet