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CL

Co-Founder & CTO

CleraSan Francisco🇺🇸United StatesPosted Oct 2, 2026

Quick Overview

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

Job Description

About the Role

Join an AI-powered creative advertising company as a full-time technical co-founder and own its technical and research direction. You will develop a proprietary platform for training and evaluating creative AI, building on existing product workflows and real-world feedback.

What You'll Do

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

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

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

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

  • Make decisions about frontier models, fine-tuning, post-training, reinforcement learning, and original research.

  • Build reliable production infrastructure for creative workflows, experimentation, training, and inference.

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

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

What We're Looking For

  • Typically 3 to 20 years of relevant experience, with hands-on experience building preference or reward models, RLHF, ranking, or evaluation systems.

  • Experience applying causal inference to observational data, including selection bias, counterfactual or off-policy evaluation, and adaptive experimentation.

  • Have shipped products or features used by people and worked on production ML tied to business outcomes, such as ads, marketplaces, recommenders, or ranking.

  • Strong Python and production ML infrastructure experience, plus ownership of a model, evaluation, or infrastructure program end to end.

  • Experience with noisy, delayed, or subjective outcomes; bandits, sequential allocation, multimodal systems, or agents is valued.

  • Track record recruiting and leading technical talent, and willingness to commit full-time as an equal co-founder in an early-stage environment.

Compensation & Benefits

Approximately 28% equity as an equal co-founder. Cash compensation is discussed based on circumstances and fit. Visa sponsorship is not available.

Location

On-site in San Francisco, California, United States.