[Remote] Research Scientist Intern (Data-TnS-Algo-Foundations & Intelligence Service)- 2026 Start (PhD)

Note: The job is a remote job and is open to candidates in USA. TikTok is the leading destination for short-form mobile video, and they are seeking a Research Scientist Intern to contribute to their foundation-model team focused on LLM and VLM capabilities. This internship will provide hands-on experience in developing approaches to improve AI safety and capability while collaborating with industry experts. Responsibilities Explore and develop approaches that improve general capability and safety for LLMs and VLMs via pretraining/CPT Build advanced evaluation systems to study emerging LLM/VLM skills and safety behaviors, aligned with real downstream use Develop advanced reinforcement-learning strategies (e.g., RLHF/RLAIF/DPO variants), and investigate how to balance pretraining and post-training for better capability and safety alignment Probe new failure modes and pitfalls in scaffolded environments (agents, workflows, tool use), and translate insights into robust mitigations Skills Currently pursuing a PhD in Computer Science or a related technical field Research experience in at least one of: LLMs, AI Safety, Computer Vision, Multimodality Actively track recent AI-safety developments (familiar with current papers, benchmarks, and terminology) Proficient with at least one deep learning framework (e.g., PyTorch, TensorFlow) Excellent analytical/problem-solving ability, clear logical thinking, and strong communication/collaboration skills Publications in top AI or Security venues (e.g., NeurIPS, ICLR, ICML, COLM, CVPR, ICCV, ECCV, USENIX Security, ACM CCS, IEEE S&P, NDSS) Benefits Day one access to health insurance Life insurance Wellbeing benefits 10 paid holidays per year Paid sick time (56 hours if hired in first half of year, 40 if hired in second half of year) Housing allowance Company Overview TikTok is a short-form video entertainment app and social network platform. It is a sub-organization of ByteDance. It was founded in 2003, and is headquartered in Los Angeles, California, USA, with a workforce of 10001+ employees. Its website is Company H1B Sponsorship TikTok has a track record of offering H1B sponsorships, with 979 in 2025, 601 in 2024, 387 in 2023, 322 in 2022, 133 in 2021, 72 in 2020. Please note that this does not guarantee sponsorship for this specific role.