AI Engineer (LLM/Multimodal) Graduate - TikTok Search

About the role

ByteDance's Search Team builds and owns its search engine, combining information retrieval with machine learning methods such as NLP, computer vision, multimodal learning and recommender systems. It is looking for a graduate (PhD) to join the team, starting in 2027, to work on LLM-powered and multimodal search. Candidates must be able to commit to an onboarding date by the end of the year.

Key responsibilities

• Develop and optimize algorithms for large-scale search systems, including query understanding, retrieval, ranking, reranking and relevance modeling.
• Apply machine learning, deep learning and foundation model technologies to improve search relevance, personalization and user satisfaction.
• Explore LLM-powered search technologies such as generative search, retrieval-augmented generation, search agents, long-context understanding and multi-turn search.
• Build and improve multimodal search using text, image, video, audio, user behavior and other content signals.
• Work with product, engineering and research teams to turn research ideas into production deployments.
• Run data analysis, model evaluation and online/offline experiments to improve the search experience.

Required profile

• Completing or recently completed a PhD in Software Development, Computer Science, Computer Engineering or a related technical discipline.
• Hands-on experience in at least one area: search/retrieval, ranking, recommender systems, NLP, multimodal learning, LLMs or applied ML.
• Ability to conduct structured research or technical problem-solving and turn ideas into working solutions.
• Preferred: research, project or internship experience in search, ranking, NLP, multimodal learning, LLMs or AI systems; publications, open-source contributions or research projects (top-tier conference papers are a plus).

Required skills

• Solid programming in Python, C++ or a related language.
• Good understanding of machine learning and deep learning fundamentals.
• Strong analytical and problem-solving skills, good communication and collaboration skills.