Co-Founder & CTO

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.