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Co-Founder & CTO

CleraSan Francisco🇺🇸United StatesPosted Sep 27, 2026

Why This Role Stands Out

As a Co-Founder & CTO, you will shape the technical and research strategy of an innovative AI marketplace from its inception, with significant equity and the chance to build groundbreaking data infrastructure and evaluation systems. This is an exceptional opportunity for a visionary leader with hands-on experience in preference modeling and causal inference to drive the future of creative AI. Apply now to join a dynamic early-stage venture and leave your indelible mark.

Quick Overview

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

Job Description

About the Role

This is an equal co-founder opportunity, not a conventional senior hire. You will own all technical and research strategy at an early-stage creative AI marketplace, joining at the ground floor with meaningful equity and full responsibility for shaping the product, the data infrastructure, and the research roadmap.

What You'll Do

  • Own technical and research strategy end to end, from current workflows to a proprietary training and evaluation platform for creative AI agents.

  • Build data infrastructure that connects briefs, creator submissions, generation traces, decisions, critique, and campaign outcomes.

  • Design systems that evaluate, rank, critique, generate, and continuously improve creative work.

  • Develop the allocation policy that directs campaign budget and simultaneously shapes dataset collection.

  • Make core decisions on frontier model usage, fine-tuning, post-training, reinforcement learning, and original research directions.

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

  • Recruit and lead the first engineering and research team.

  • Work directly with creators, brands, and investors.

What We're Looking For

  • Hands-on experience building preference or reward models, including RLHF, reward modeling, ranking subjective outputs, or evaluation systems.

  • Comfort with causal inference on observational data: selection bias, off-policy or counterfactual evaluation, adaptive experimentation, or validating cheap proxies against delayed outcomes.

  • Production ML experience in ads, marketplace, recommender, or ranking systems tied to real business outcomes.

  • Experience with bandits, sequential allocation, or online experimentation at scale.

  • A track record of shipping real products or features used by real people, not only research prototypes.

  • Experience owning a model, evaluation, or infrastructure program end to end.

  • Experience recruiting and leading strong technical teams.

  • Background at a frontier AI lab or research organization of comparable caliber is a strong signal.

  • Multimodal generation, agents, planning systems, or latent-variable modeling experience is valued.

  • Prior founder experience, including ventures that have since ended, is a plus.

  • High agency, intellectual honesty, low ego, and genuine curiosity about creativity and human feedback.

  • Able to commit full-time, in person in San Francisco, as an equal co-founder.

Compensation & Benefits

  • Equity: approximately 28% as an equal co-founder

  • Cash compensation: discussed directly based on circumstances and fit

Location

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