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# Principal Software Engineer

- **Company:** Roblox
- **Location:** San Mateo, CA, United States
- **Experience:** Expert
- **Salary:** $345,040.0
- **Contract:** Permanent contract
- **Skills:** Artificial Intelligence, Large Language Models, Backend, Agentic-AI, Information Technology, Machine Learning Operations
- **Published:** November 5, 2026
- **Apply:** https://careers.roblox.com/jobs/8221568?gh_jid=8221568

## About the Role

* 8+ years of experience building and operating large-scale distributed systems, including technical leadership across multiple teams.
 * Deep experience designing backend platforms used by other engineering teams.
 * Hands-on experience with production AI/ML systems, such as model serving, orchestration, LLM integration, or agentic execution loops (planning, tool use, recovery, long-running workflows).
 * A strong understanding of tool and skill design and structured evaluation for AI systems.
 * The judgment to weigh tradeoffs and make pragmatic calls under ambiguity.
 * A BS in Computer Science or a related field, or equivalent professional experience.

## Description

* Excited to define how AI agents create at scale, and to stay hands-on while doing it.
 * A clear communicator who can explain complex technical direction to engineers, product, and leadership.
 * Experienced with workflow engines (e.g., Temporal), multi-provider model routing, or AI cost management (bonus).

You Will:

 * Own the technical architecture and long-term roadmap for the Build agent platform.
 * Design for reliability, safety, observability, and cost efficiency in production AI workloads, including usage metering and model-routing strategy.
 * Define how we measure agent quality and build the evaluation infrastructure that drives model, prompt, and skill decisions.
 * Partner with Build product teams, ML infrastructure, and Safety to ship new capabilities quickly and safely.
 * Raise the engineering bar through design reviews, mentorship, and hands-on technical leadership.