Backend Engineer: LLM Agent Platform & AI Tools (Equity)

Anduril Industries; Washington (District of Columbia); On-site; USD 220,000 - 292,000; Full time

Job summary

Anduril Industries is seeking 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. Responsibilities include owning core framework abstractions, supporting multiple business lines, and

Qualifications

• Strong backend engineering experience building production-quality platforms, APIs, or infrastructure used by other engineers.
• Deep expertise in LLM agent framework design and orchestration patterns (linear, graph, multi-agent).
• Experience designing agent evaluation paradigms (trajectories, rubric grading, human-in-the-loop).
• Familiarity with model post-training workflows such as SFT, RL, and environment-based training.
• Strong judgement around reliability, observability, debugging, and safety for LLM apps in high-stakes settings.
• Ability to work with partner teams, translate needs into reusable platform capabilities.

Responsibilities

• Own Anduril’s internal LLM agent framework, including core abstractions, runtime, and reliability.
• Support multiple business lines by providing new framework capabilities and architectural reviews.
• Partner with ML teams to streamline model post-training workflows (supervised fine-tuning to RL).
• Design tooling for modern agent patterns: tool calling, memory, planning loops, and subagents.
• Build comprehensive evaluation suites: task success, tool-calls, trajectory quality, regressions.
• Stay current on agent architecture trends and pragmatic adoption decisions.

Skills

Backend engineering

LLM agent design

Model post-training

Observability & reliability

Cross-team collaboration

Tools

Kubernetes

Docker

Job description

Anduril Industries is seeking 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. Responsibilities include owning core framework abstractions, supporting multiple business lines, and