Staff Applied Scientist - AI Evaluation & Trust

About Sayari: Sayari is a venture-backed and founder-led global corporate data provider and commercial intelligence platform that serves financial institutions, legal and advisory service providers, multinationals, journalists, and governments. Thousands of analysts and investigators in over 30 countries rely on our products to safely conduct cross-border trade, research front-page news stories, confidently enter new markets, and prevent financial crimes such as corruption and money laundering. Our company culture is defined by a dedication to our mission of using open data to prevent illicit commercial and financial activity, a passion for finding novel approaches to complex problems, and an understanding that diverse perspectives create optimal outcomes. We embrace cross-team collaboration, encourage training and learning opportunities, and reward initiative and innovation. If you like working with supportive, high-performing, and curious teams, Sayari is the place for you. POSITION DESCRIPTION Sayari builds AI systems for high-consequence analytical work where being "wrong" carries real-world weight. We are looking for a Staff or Principal Applied Scientist to join our AI Innovation Group as the trusted expert on AI Evaluation and Trust. You will own the "Judgment Layer" of our system: building the specialized judge models, statistical benchmarks, and multi-turn frameworks that ensure our agents act with the high bar of trustworthiness required by our national security and enterprise customers. JOB RESPONSIBILITIES Lead the development of specialized "judge models," moving from general-purpose frontier models to architectures purpose-built for evaluation and failure mode detection. Design and execute rigorous scoring pipelines and empirical threshold calibrations for agentic systems, including multi-turn conversation and Graph RAG reasoning. Establish domain-specific evaluation frameworks that measure whether a system can perform the work of human experts rather than just passing general capability benchmarks. Own the full lifecycle of evaluation data, from designing annotation infrastructure and protocols to deploying evaluation services into production. Research and implement advanced techniques in Mixture-of-Experts (MoE) routing, expert specialization evaluation, and ensemble calibration. Collaborate cross-functionally with Product, Data Engineering, and the SVP of AI to translate complex statistical uncertainty into clear, actionable product signals. Act as a technical leader and "Scientific Conscience" within the AI pod, ensuring every AI-driven risk signal is backed by an empirical derivation story. SKILLS & EXPERIENCE Required: 10+ years of Machine Learning experience with a focus on Deep Neural Network activities, evaluating model performance & trust. 1-2+ years’ experience focused on post-training activities 1+ year experience creating benchmarks to evaluate LLMs Technical Mastery: Deep expertise in LLM-as-judge architectures, multi-turn evaluation, and Reinforcement Learning (RL/RLHF/RLAIF). Statistical Rigor: Mastery of statistics and experimental design, including significance testing, distribution analysis, and inter-rater reliability. Architectural Depth: Experience with Mixture-of-Experts (MoE) systems, routing behavior, and expert specialization. Builder Mindset: Proven ability to own the path from data collection to production deployment; we are a small team and every role is "hands-on." Domain Fluency: Understanding of Graph RAG and the unique challenges of evaluating non-deterministic, agentic workflows. Preferred: Judgment Task Models: Experience building, fine-tuning (LoRA, etc.), or pre-training models specifically for judgment, preference modeling, or classification tasks. Domain Context: Background in cognitive science, intelligence community tradecraft, or research literature on expert judgment under uncertainty. Infrastructure at Scale: Experience building or managing large-scale annotation infrastructure and quality assurance protocols. Academic/Research Track Record: A record of published research or recognized work in preference modeling or AI alignment. The target base salary for this position is $195,000-$205,000 plus company bonus and equity. Final offer amounts are determined by multiple factors including location, local market variances, candidate experience and expertise, internal peer equity, and may vary from the amounts listed above. Benefits: 100% fully paid medical, vision, and dental for employees and their dependents Generous time off; we observe all US federal holidays, close our office for a winter break (12/24-12/31), in addition to granting 18 PTO days and 10 sick days Outstanding compensation package; competitive commissions for revenue roles and bonuses for non-revenue positions A strong commitment to diversity, equity, and inclusion Eligibility to participate in additional benefits such as 401k match up to 5%, 100% paid life insurance (up to $100,000 coverage),, and parental leave A collaborative and positive culture - your team will be as smart and driven as you Limitless growth and learning opportunities Sayari is an equal opportunity employer and strongly encourages diverse candidates to apply. We believe diversity and inclusion mean our team members should reflect the diversity of the United States. No employee or applicant will face discrimination or harassment based on race, color, ethnicity, religion, age, gender, gender identity or expression, sexual orientation, disability status, veteran status, genetics, or political affiliation. We strongly encourage applicants of all backgrounds to apply. Pay Range $195,000—$205,000 USD