Software Engineer, Agent Platform

Anduril Industries • Columbia, WA

3d

About The Position

Frontier AI is looking for a backend software engineer to own and evolve our internal LLM agent framework. This role sits at the intersection of backend infrastructure, applied AI, agent architecture, model post-training, and evaluation tooling. You will build the platform that enables teams across Anduril to develop, evaluate, and deploy reliable LLM agents in mission-critical environments.

Requirements

• Strong backend engineering experience building production-quality platforms, frameworks, APIs, or infrastructure used by other engineers.
• Deep expertise in LLM agent framework design, including the tradeoffs between different orchestration patterns such as linear agents, graph-based agents, multi-agent systems, planner/executor loops, and tool-heavy agents.
• Experience designing agent evaluation paradigms, including trajectory evaluations, LLM-as-judge workflows, task-success metrics, tool-call correctness checks, rubric-based qualitative grading, adversarial scenario testing, regression eval suites, and human-in-the-loop review.
• Familiarity with model post-training workflows such as SFT, preference tuning, reinforcement learning, and environment-based agent training.
• Strong judgment around reliability, observability, debugging, and safety for LLM applications deployed in high-stakes settings.
• Ability to work directly with partner teams, understand ambiguous product needs, and turn them into reusable platform capabilities.

Nice To Haves

• Experience with agent frameworks like Langchain Deepagents, Claude SDK, etc.
• Experience building evaluation platforms, simulation environments, benchmark suites, or agent test harnesses.
• Experience with Kubernetes, Docker, distributed systems, workflow orchestration, or ML infrastructure.
• Familiarity with defense, robotics, command-and-control systems, autonomy, or operational planning domains.

Responsibilities

• Own Anduril’s internal LLM agent framework, including core abstractions, runtime architecture, developer experience, integrations, and reliability.
• Support multiple business lines building LLM agents by providing new framework capabilities, implementation guidance, architectural reviews, and best-practice patterns.
• Partner with machine learning teams to make model post-training workflows easy to integrate, ranging from supervised fine-tuning to offline RL, online RL, and environment-driven agent improvement.
• Design tooling that supports modern agent patterns, including structured tool calling, filesystem-using agents, memory and retrieval, planning loops, subagents, agent graphs, and human-in-the-loop workflows.
• Work with partner teams to define comprehensive evaluation suites that measure task success, tool-call correctness, trajectory quality, robustness, regressions, and deployment readiness.
• Stay current on emerging agent architecture and evaluation trends, and make pragmatic decisions about which techniques should or should not be adopted internally.

Benefits

• Highly competitive equity grants are included in the majority of full time offers; and are considered part of Anduril's total compensation package.
• Top-tier benefits for full-time employees, including: comprehensive, competitive benefits package (available at little to no cost to employees) ensures you’re supported in health, recovery, and whatever comes next.

What This Job Offers

• Job Type: Full-time
• Career Level: Senior
• Education Level: No Education Listed