Harness Engineer

The role

You will own the intelligence layer between AI models and the product. This includes system prompts, tool definitions, context management, and the evaluation framework.

What you will do

• Build and refine system prompts, tool integrations, and context windows
• Design the evaluation framework including LLM-as-judge evals, deterministic tests, and production monitoring
• Architect the abstraction layer between the product and model capabilities
• Own prompt versioning, experimentation, and iteration
• A/B test prompt variations and measure impact on agent quality
• Collaborate with product and engineering to identify signal and translate it into improvements

Required qualifications

• High agency and self-direction
• Small-team intensity comfort
• Unorthodox problem solving
• Quality-driven execution
• Low ego and accountability

Nice to have

• background in English, literature, creative writing, or humanities

Benefits

• Work directly with the founders
• Meaningful equity as part of the founding team
• 100 percent paid medical, dental, and vision
• 401(k) plan
• $1k monthly wellness and meals stipend
• Relocation support for San Francisco
• Company-wide annual off-sites
• High ownership, high trust, fast progression
• In-person culture with a deep commitment to excellence

About the company

Virio is building the next-generation B2B GTM stack. They turn executive-led content into revenue for fast-growing B2B companies by building content engines.