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CL

Co-Founder & CTO

CleraSan Francisco🇺🇸United StatesPosted Oct 10, 2026

Quick Overview

Seniority
Leader
Employment type
Full Time
Work mode
On Site
Location
San Francisco, United States
Posted
4 hours ago
Recruiting

Job Description

About the Role

Join an AI-powered creative advertising startup as a full-time technical co-founder and CTO. You will own the technical and research direction, building on an existing product to develop systems that learn from creative work and its real-world performance.

What You'll Do

  • Set the technical and research strategy, from current workflows through a proprietary training and evaluation platform.

  • Build data infrastructure connecting creative briefs, submissions, generation traces, decisions, feedback, and campaign outcomes.

  • Develop systems to evaluate, rank, critique, generate, and improve creative work.

  • Design allocation policies that direct campaign budgets and inform data collection.

  • Choose where to apply frontier models, fine-tuning, post-training, reinforcement learning, and original research.

  • Build reliable infrastructure for creator workflows, campaigns, experimentation, model training, and inference.

  • Set standards for data quality, consent, privacy, measurement, and model evaluation.

  • Recruit and lead the first engineering and research team, while working directly with creators and brands.

What We're Looking For

  • At least 3 years of relevant experience, with hands-on work building preference or reward models, including RLHF, ranking, or evaluation systems.

  • Experience with causal inference on observational data, such as selection bias, off-policy evaluation, counterfactual analysis, or adaptive experimentation.

  • A track record of shipping products used by people, building production ML infrastructure, and owning model, evaluation, or infrastructure programs end to end.

  • Background in ads, marketplaces, recommenders, or ranking systems tied to business outcomes, including experience with noisy, delayed, or subjective feedback.

  • Strong technical leadership and recruiting experience. Bandits, sequential allocation, multimodal systems, agents, or latent-variable modeling are valuable.

  • Ready to work full time, in person, as an equal co-founder in an early-stage environment.

Compensation & Benefits

Equity of approximately 28% as a co-founder. Cash compensation is discussed based on circumstances and fit. Visa sponsorship is not available.

Location

On-site in San Francisco, California.

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