Research Engineer Intern (Agentic Systems & AI Infrastructure - TikTok-Generalized Arch) - 2027 Start (PhD)

TikTok is an international short video platform available in over 150 countries and regions, where we aim to inspire creativity and bring joy by helping people discover authentic and interesting moments. TikTok has offices around the world, with global headquarters in Los Angeles and Singapore, and additional offices in New York, London, Dublin, Paris, Berlin, Dubai, Jakarta, Seoul, and Tokyo.

The TikTok Agentic Arch team is building AI-native engineering infrastructure that transforms how software is designed, built, and operated at TikTok scale. We research and deploy reliable long-horizon agents that can reason over large codebases, interact with complex tools and environments, and complete consequential engineering work across distributed production systems. Our environment provides a unique opportunity to advance agent research through real-world execution feedback.

About the role

You will develop frontier methods, evaluate them rigorously, and bring them into production through platforms used at large scale—creating measurable improvements in engineering productivity, software quality, and operational effectiveness. This internship blends hands-on learning, community-building, and professional development while collaborating with industry experts.

Responsibilities

• Pursue or recently complete a PhD in Computer Science or a related field, with relevant work in machine learning, natural language processing, software engineering, distributed systems, programming languages, or a related area.
• Demonstrate research or engineering experience in AI agents or closely related areas such as large language model reasoning, reinforcement learning, program synthesis, or AI for code.
• Apply strong understanding of agent planning and reasoning, model post-training, reinforcement learning, memory and context systems, tool learning, multi-agent systems, or agent evaluation.
• Build robust implementations in Python, C++, Go, Java, or similar languages, turning research ideas into production-ready systems.
• Formulate ambiguous real-world problems, design rigorous experiments, analyze results, and iterate based on evidence.
• Collaborate across research, infrastructure, platform, and product teams with strong communication skills.

Qualifications

• Minimum Qualifications:
  • Currently pursuing or recently completed a PhD in Computer Science or a related field.
  • Demonstrated research or engineering experience in AI agents or related areas (e.g., LLM reasoning, reinforcement learning, program synthesis, AI for code).
  • Strong understanding of agent planning, model post-training, reinforcement learning, memory systems, tool learning, multi-agent systems, or evaluation.
  • Proficiency in Python, C++, Go, Java, or similar languages with a track record of robust implementations.
  • Ability to design experiments, analyze results, and iterate on real-world problems.
  • Strong communication and collaboration skills.
• Preferred Qualifications:
  • Evidence of research excellence through publications (NeurIPS, ICML, ICLR, ACL, MLSys, OSDI, SOSP, NSDI, ICSE, FSE), open-source contributions, or deployed systems.
  • Experience building or deploying LLM agents, AI developer tools, or agent platforms in large-scale environments.
  • Hands-on experience with model post-training, reinforcement learning, execution-feedback loops, tool-using agents, distributed runtimes, or scalable evaluation systems.
  • Experience with large codebases, distributed systems, CI/CD, testing infrastructure, developer platforms, or production operations.
  • A track record of translating research into measurable production impact.

All successful candidates must be able to establish authorization to work in the United States without sponsorship.

Pay

The hourly rate for this internship position is $60.

Benefits

• Day-one access to health insurance, life insurance, and wellbeing benefits.
• 10 paid holidays per year and paid sick time (56 hours if hired in the first half of the year, 40 if hired in the second half).
• Eligibility for housing allowance (for non-remote interns).