Machine Learning/AI Scientist Intern (PhD), 2026

bolthires is one of the world's leading entertainment services, with over 300 million paid memberships in over 190 countries enjoying TV series, films and games across a wide variety of genres and languages. Members can play, pause and resume watching as much as they want, anytime, anywhere, and can change their plans at any time. Machine Learning Research at bolthires improves various aspects of our business, including personalization algorithms, member and title understanding, creative tooling, system optimization, and innovative tooling.Our research spans many areas of machine learning, including recommender systems, reinforcement learning, computer vision, natural language processing, optimization, causality, and operations research. Great applied research also requires robust machine learning infrastructure, another strong emphasis at bolthires. Candidates will be evaluated to find the best fit in one of our organizations, including Content, Choosing & Conversation, Commerce or AI for Member Systems. You can find a detailed list of teams across these organizations to learn more.Applicants are encouraged to express their interest in one or multiple types of teams/ domain areas listed if your skills and qualifications are aligned. We are looking for individuals with the following qualifications: Currently enrolled student pursuing an advanced degree (PhD) in areas such as Computer Science, Machine Learning, Artificial Intelligence, Computer Engineering, Mathematics, Statistics, Data Science, Economics, Computational Biology, Chemistry, Physics, Cognitive Science or a related field Domain expertise in one or more of the following areas: Personalization & Recommender Systems: Using Transformers/LLMs for recommendations, collaborative filtering, content-based recommendation, hybrid systems, and conversational recommenders.Natural Language Processing (NLP): Large Language Models (LLMs), fine-tuning, in-context learning, prompt engineering, alignment, evaluation, text generation, and embeddings. Reinforcement Learning (RL): Offline and online RL, alignment and post-training, preference- and human-feedback-based learning, bandit algorithms. Computer Vision (CV): Image and video understanding, generation, and representation learning. Computer Graphics: 3D modeling and understanding, neural rendering, animation, and related areas.Reliable ML : Robustness, explainability, interpretability. Causal ML: Causal inference, causal discovery, double ML, policy learning, dynamic panel and dynamic choice modeling, matrix completion for counterfactuals. Agentic AI : Developing and evaluating agentic systems that reason, plan, and act autonomously, including tool use, retrieval-augmented reasoning, memory and goal management, and feedback-driven learning. Multimodal Data: Experience in large vision language models, modality fusion and alignment, multimodal retrieval.Experience handling and integrating text, image, video, audio, and other data sources. Model Optimization and Efficiency : Training and inference efficiency, model benchmarking, optimization techniques. ML Platform & Infrastructure: Designing and building scalable systems for model development, training, and deployment, managing large-scale data pipelines and distributed compute environments. General ML Application Engineering: Implementing machine learning solutions across various domains, end-to-end ML pipelines, from experimentation to deployment.Experience programming in at least one programming language (Python, Java, Scala, or C/C++) Familiarity developing ML models using common frameworks (e.g., PyTorch, TensorFlow, Keras) and training on GPUs. Familiarity with distributed training and inference paradigms and associated frameworks (eg. DDP, FSDP, HSDP, Deepspeed) Familiarity with end-to-end machine learning pipelines (e.g. training or production deployment) and common challenges like explainability. Curious, self-motivated, and excited about solving open-ended challenges at bolthires.Great communication skills, both oral and written. Nice to have: Comfortable with distributed computing environments such as Spark or Presto. Comfortable with software engineering best practices (e.g. version control, testing, code review, etc.). For your application to be considered complete You will be sent an Airtable form shortly after you on our careers site; your application will not be considered complete until you fill out and submit this form. Include a Resume or CV with complete contact information (email, phone, mailing address) and a list of relevant coursework and publications (if applicable).You will be asked to include a short statement describing your research experiences and interests, and (optionally) their relevance to bolthires Research.For inspiration, have a look at the bolthires Research site. Applications will be reviewed on a rolling basis and it’s in the applicant's best interest to apply early. The application window will remain open until roles are filled. About the Internship Program At bolthires, we offer a personalized experience for interns, and our aim is to offer an experience that mimics what it is like to actually work here. We match qualified interns with projects and groups based on interests and skill sets, and fully embed interns within those groups for the summer.bolthires is a unique place to work and we live by our values, so it's worth learning more about our culture. Internships are paid and are a minimum of 12 weeks, with a choice of fixed start dates in January 2026 (Winter), May or June 2026 (Summer) to accommodate varying school calendars. Our summer internships will be located at our headquarters in Los Gatos, CA, with limited opportunities in Los Angeles or New York depending on the team. This program is intended for students who will be returning to school for at least one semester/quarter following the internship to be eligible for full time employment.Conversion or return offers are based on business need and headcount, and are not guaranteed. At bolthires, we carefully consider a wide range of compensation factors to determine the Intern top of market. We rely on market indicators to determine compensation and consider your specific job, skills, and experience to get it right. These considerations can cause your compensation to vary and will also be dependent on your location. The overall market range for bolthires Internships is typically $40/hour - $85/hour.This market range is based on total compensation (vs. only base salary), which is in line with our compensation philosophy. bolthires is a unique culture and environment. Learn more here. Inclusion is a bolthires value and we strive to host a meaningful interview experience for all candidates. If you want an accommodation/adjustment for a disability or any other reason during the hiring process, please send a request to your recruiting partner. We are an equal-opportunity employer and celebrate diversity, recognizing that diversity builds stronger teams.We approach diversity and inclusion seriously and thoughtfully. We do not discriminate on the basis of race, religion, color, ancestry, national origin, caste, sex, sexual orientation, gender, gender identity or expression, age, disability, medical condition, pregnancy, genetic makeup, marital status, or military service. Job is open for no less than 7 days and will be removed when the position is filled.