Machine Learning Engineer, Ads

WHY WORK AT HIGGSFIELD AI? Higgsfield AI is the fastest-scaling generative AI company in history, hitting $700M in annual revenue run rate, 30M+ users worldwide, 6M+ generations per day, and powering 390 of Fortune 500 brands. We're building at the absolute frontier of AI-powered video creation and next-generation creative tools. Joining Higgsfield means becoming part of a high-impact team shaping the future of AI-native experiences, at a company that isn't just moving fast, but rewriting what fast looks like. ABOUT THE ROLE We're looking for exceptional Machine Learning Engineers focused on Ads to help take Higgsfield's advertising platform to the next level. You'll work at the intersection of large-scale machine learning, generative AI, and advertising systems—building the models and infrastructure that determine how creative is generated, ranked, optimized, and ultimately performs. This role is for someone who understands ads systems deeply and is equally strong in modern generative AI. You should be comfortable moving across ranking and recommendation, targeting and optimization, prompt engineering, post-training, and production ML systems. You'll help define what an AI-native advertising platform looks like from the ground up. WHAT YOU'LL DO: - Build and improve ML systems powering advertising products, including ranking, recommendation, targeting, prediction, and optimization. - Develop models that improve ad creative quality, relevance, personalization, and performance at scale. - Build systems that connect generative models with real-world advertising performance signals, creating feedback loops that continuously improve model outputs. - Apply prompt engineering and post-training techniques to improve generative models for advertising and creative use cases. - Work on fine-tuning, preference optimization, evaluation, and other techniques for adapting foundation models to specific creative and advertising objectives. - Design and run experiments across creati