Staff Machine Learning Engineer, Ads Creative Effectiveness

Reddit is a community-driven platform built around shared interests, passion, and trust. The Staff Machine Learning Engineer will develop generative AI and predictive products for advertising creative, including image, video, and copy generation, performance-guided optimization, editing pipelines, and safety systems. The role also partners with Product, Sales, Policy, UX, and Ads ML teams to integrate these capabilities into advertising products.

Responsibilities:

• Architect and implement state-of-the-art pipelines for ad creative generation. You will move beyond vanilla prompting to build systems capable of product, font, logo and brand asset preservation using techniques like IP-Adapters, and LoRAs
• Build editing capabilities allowing advertisers to smart-crop, inpaint, outpaint, resize, and style-transfer assets while maintaining strict brand guidelines
• Adapt large vision-language models to understand "winning" ad aesthetics. You will build feedback loops where ad performance metrics (CTR, CVR) are used to fine-tune the generation process (RLHF/RLPF for Ads)
• Engineer robust filtering and safety systems. You ensure our models never generate non-compliant, unsafe, or copyright-infringing content
• Collaborate with Product, Sales, Policy, UX, and sibling Ads ML teams to integrate ACE capabilities into the Ad Manager UI and the ad delivery path
• Embed brand-safety filters, copyright checks, and human-in-the-loop escalation paths to protect users and advertisers

Requirements:

• Hands-on experience with tree models, neural nets, ranking, and especially LLM/VLM fine-tuning & RLHF/RLPF for ads
• Comfort with uplift metrics, variance, minimum detectable effects and experimentation setups for generative systems
• Understanding auction dynamics and advertiser pain points to create tools that drive revenue and retention
• Bias to action, comfort with ambiguity, and scrappiness: ACE evolved from a startup acquisition and still moves fast
• Able to distill complex ML trade-offs for executives, product managers, and non-technical stakeholders alike
• Prior work on ad creative tooling: Headline generators, image generators, pre-test models, editing flows for the advertiser
• Experience navigating brand-safety, privacy, or copyright frameworks in generative AI products