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PerplexityPerplexitySan Francisco, CA

Model Behavior Architect

Designs prompt and context engineering strategies for AI products, builds evaluation pipelines, and ensures model quality and behavioral consistency. Requires 3+ years with LLMs, Python experience, and expertise in AI evaluations.

180k – 260k/yr
On-siteML Engineering

About the role

Key Responsibilities

  • Context Engineering: Design, test, and optimize context strategies and system prompts that shape answer engine behavior across products, features, and use cases.
  • Evaluation Systems: Build automated and semi-automated evaluation pipelines that measure model quality, catch regressions, and scale across product surfaces.
  • Model Launch Support: Partner with research and engineering to validate model behavior before and during rollouts, ensuring smooth transitions with no degradation.
  • Research & Analysis: Identify inconsistencies and failure modes in model outputs through well-designed research projects — for both internal and production-facing systems.
  • Cross-functional Collaboration: Work closely with design, product, and research teams to translate product goals into concrete model behavior requirements.
  • Knowledge Sharing: Help engineers across teams build intuition for prompt design, context engineering, and evaluation best practices.
  • Staying Current: Track the latest alignment, evaluation, and prompting techniques from industry and academia, and bring the best ideas back to the team.

What We're Looking For

Required

  • Experience designing evaluations, benchmarks, or metrics for AI systems.
  • Strong written and verbal communication skills, particularly in explaining complex concepts to diverse stakeholders.
  • Ability to manage multiple concurrent projects in a fast-moving environment.
  • Strong experience with Perplexity or other frontier AI models in production settings.
  • Demonstrated experience with Python — you'll prototype, debug, automate, and build systems at scale.
  • 3+ years of experience working with LLMs in a product or research setting.

Preferred

  • Experience with A/B testing or experimentation frameworks.
  • Track record of improving AI system performance through systematic evaluation and iteration.

Skills

PythonLLMsPrompt EngineeringContext EngineeringAi EvaluationsBenchmarksA/B TestingPerplexity Ai

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