Staff Machine Learning Engineer, Ads Creative Effectiveness

Reddit is a community of communities. It’s built on shared interests, passion, and trust, and is home to the most open and authentic conversations on the internet. Every day, Reddit users submit, vote, and comment on the topics they care most about. With 100,000+ active communities and approximately 130 million daily active unique visitors, Reddit is one of the internet’s largest sources of information. For more information, visit www.redditinc.com. About the Role Reddit’s Ads Creative Effectiveness team sits at the heart of our creative strategy, building GenAI and predictive products that help advertisers ship high-impact campaigns. We are searching for a Staff engineer with in-depth GenAI expertise that can help us build the future of generative products for ad creative at Reddit - best-in-class image, video and copy generators that leverage Reddit’s best practices, performance-guided generations that maximize clicks and conversions, and brand safe, product preserving image/video editing pipelines. What you’ll do: • Advanced Generative Workflows: 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. • End-to-End Image & Video Editing: Build editing capabilities allowing advertisers to smart-crop, inpaint, outpaint, resize, and style-transfer assets while maintaining strict brand guidelines. • LLM/VLM Fine-Tuning: 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). • Safety & Compliance Layer: engineer robust filtering and safety systems. You ensure our models never generate non-compliant, unsafe, or copyright-infringing content. • Partner Broadly: 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. • Guardrails & Safety: Embed brand-safety filters, copyright checks, and human-in-the-loop escalation paths to protect users and advertisers. What we’re looking for: • Deep ML Expertise: Hands-on experience with tree models, neural nets, ranking, and especially LLM/VLM fine-tuning & RLHF/RLPF for ads. • Quant & Experimentation Chops: Comfort with uplift metrics, variance, minimum detectable effects and experimentation setups for generative systems. • Ads / Marketplace Insight: Understanding auction dynamics and advertiser pain points to create tools that drive revenue and retention. • Startup Mindset: Bias to action, comfort with ambiguity, and scrappiness: ACE evolved from a startup acquisition and still moves fast. • Communication Superpowers: 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. Nice-to-have • Experience navigating brand-safety, privacy, or copyright frameworks in generative AI products. Benefits: • Comprehensive Healthcare Benefits and Income Replacement Programs • 401k with Employer Match • Global Benefit programs that fit your lifestyle, from workspace to professional development to caregiving support • Family Planning Support • Gender-Affirming Care • Mental Health & Coaching Benefits • Flexible Vacation & Paid Volunteer Time Off • Generous Paid Parental Leave Pay Transparency: This job posting may span more than one career level. In addition to base salary, this job is eligible to receive equity in the form of restricted stock units, and depending on the position offered, it may also be eligible to receive a commission. Additionally, Reddit offers a wide range of benefits to U.S.-based employees, including medical, dental, and vision insurance, 401(k) program with employer match, generous time off for vacation, and parental leave. To learn more, please visit https://www.redditinc.com/careers/. To provide greater transparency to candidates, we share base salary ranges for all US-based job postings regardless of state. We set standard base pay ranges for all roles based on function, level, and country location, benchmarked against similar stage growth companies. Final offer amounts are determined by multiple factors including, skills, depth of work experience and relevant licenses/credentials, and may vary from the amounts listed below. The base salary range for this position is: $230,000—$322,000 USD In select roles and locations, the interviews will be recorded, transcribed and summarized by artificial intelligence (AI). You will have the opportunity to opt out of recording, transcription and summarization prior to any scheduled interviews. During the interview, we will collect the following categories of personal information: Identifiers, Professional and Employment-Related Information, Sensory Information (audio/video recording), and any other categories of personal information you choose to share with us. We will use this information to evaluate your application for employment or an independent contractor role, as applicable. We will not sell your personal information or disclose it to any third party for their marketing purposes. We will delete any recording of your interview promptly after making a hiring decision. For more information about how we will handle your personal information, including our retention of it, please refer to our Candidate Privacy Policy for Potential Employees and Contractors. Reddit is proud to be an equal opportunity employer, and is committed to building a workforce representative of the diverse communities we serve. Reddit is committed to providing reasonable accommodations for qualified individuals with disabilities and disabled veterans in our job application procedures. If, due to