About Ethos Ethos is a leading life insurance technology company on a mission to protect families by democratizing access to life insurance and empowering agents at scale.
Performance Engineer (C++, Python, Rust)
United States
$70 – $110/hr
July 16, 2026
Job description
Role Overview
Cincinnatus LLC is seeking experienced Performance Engineers with deep expertise in low-level systems optimization using C++, Python, and Rust. In this role, you will help develop next-generation AI systems by creating, evaluating, and improving performance engineering tasks that generate high-quality training data for frontier Large Language Models.
This is a full-time W-2 opportunity where you will collaborate with a leading AI lab to improve AI model performance through systems programming, compiler engineering, runtime optimization, and infrastructure performance evaluation.
Key Responsibilities
Develop Performance Engineering Tasks
Design challenging performance engineering tasks covering:
- Systems programming
- Runtime optimization
- Compiler engineering
- AI infrastructure performance
- Systems design
Write accurate, well-structured reference solutions.
Evaluate Technical Solutions
- Review performance engineering solutions.
- Assess correctness, efficiency, scalability, and code quality.
- Provide detailed written technical feedback.
Improve AI Training Data
- Develop evaluation guidelines and detailed scoring rubrics.
- Help research teams close knowledge gaps in:
- Systems optimization
- Runtime performance
- Compiler technologies
- AI model training and inference
Collaborate Across Teams
- Work closely with engineering and research teams.
- Ensure consistency and technical accuracy across AI training datasets.
Required Qualifications
2+ years of professional experience in:
- Performance Engineering
- Systems Programming
- Low-level Systems Optimization
Deep hands-on expertise in at least one of:
- C++
- Python
- Rust
Working familiarity with the remaining languages is highly desirable.
Demonstrated success improving production system performance through:
- Latency reduction
- Throughput optimization
- Memory footprint reduction
Strong written communication skills.
Ability to work full-time (40 hours per week).
Preferred Qualifications
- Experience with:
- AI infrastructure
- Compiler engineering
- Runtime optimization
- Large-scale distributed systems
- AI model evaluation
Compensation
- $70–$110 USD per hour
Work Arrangement
- Remote (United States)
- Full-time W-2 employment
- 40 hours per week
- No outside engagements permitted
Apply now
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