Machine Learning Engineer, AI Search - USDS

About the Team

The Search team is responsible for the machine learning algorithm for Tik Tok's rapidly growing video search, e-commerce search, local service search and AI search business. We use state‑of‑the‑art large‑scale machine learning technology, cutting‑edge NLP, CV and multi‑modal technology and generative models (LLM, VLM) to build the industry's search engines to provide the best search experience, for more than 1 billion monthly Tik Tok users around the world.

Tik Tok is seeking an independent developer for the Search team. This role is pivotal in advancing Tik Tok's search capabilities by integrating cutting‑edge recommendation algorithms and large language model (LLM) technologies to deliver highly personalized and engaging user experiences.

• Independent execution:
  Independent development, experiment, analysis and deployment of large‑scale personalized search and recommendation systems, ensuring scalability, efficiency, and robustness.
• LLM Integration:
  Research and integrate LLMs within the recommendation pipeline to enhance content understanding, user intent recognition, personalization and content generation. Explore hybrid models that combine LLMs with traditional recommendation systems to mitigate feedback loops and uncover novel user interests.
• Innovation with Generative Recommendation Systems:
  Drive the integration of generative recommendation approaches, leveraging generative models to directly generate personalized content recommendations, moving beyond traditional ranking‑based methods. This includes exploring frameworks like Gen Rec, which utilize LLMs/VLMs to interpret user contexts and generate relevant recommendations.
• Cross‑functional
  
  Collaboration:
  
  Work closely with product managers, data scientists, infrastructure engineers and operation teams to enable search personalization strategies with overall product goals.

• Educational Background:
  Bachelor’s or advanced degree in Computer Science, Machine Learning, or a related field.
• Technical Expertise:
  Proficient in machine learning frameworks (e.g., Tensor Flow, PyTorch), programming languages (e.g., Python, Java, C++), and deep understanding of data structures and algorithms.
• Industry experience: 2+ years in developing large‑scale search or recommendation systems (feed, search, advertisement, etc). Familiarity with generative recommendation frameworks and their application in large‑scale systems is highly desirable.
• LLM experience:
  Hands‑on experience with deploying and improving LLMs for real‑world applications, including techniques such as prompt engineering, supervised fine‑tuning, reinforcement learning, and retrieval‑augmented generation.

• Global
  
  Experience:
  
  Experience working with international teams and understanding of diverse user behaviors across different regions.
• Open Source Contributions:
  Active participation in open‑source projects related to search, recommendation or NLP.
• Publications:
  Contributions to conferences such as NeurIPS, ICML, ACL, or Rec Sys are a plus.

USDS is committed to providing reasonable accommodations in our recruitment processes for candidates with disabilities, pregnancy, sincerely held religious beliefs or other reasons protected by applicable laws. If you need assistance or a reasonable accommodation, please reach out to us at

For Pay Transparency
:
Compensation Description (Annually)

The base salary range for this position in the selected city is $136,800 – $359,720 annually. Compensation may vary outside of this range depending on a number of factors, including a candidate’s qualifications, skills, competencies and experience, and location. Base pay is one part of the total package that is provided to compensate and recognize employees for their work, and this role may be eligible for additional discretionary bonuses/incentives, and restricted stock units.

Benefits may vary depending on the nature of employment and the country work location. Employees have day‑one access to medical, dental, and vision insurance, a 401(k) savings plan with company match, paid parental leave, short‑term and long‑term disability coverage, life insurance, wellbeing benefits, among others. Employees also receive 10 paid holidays per year, 10 paid sick days per year and 17 days of Paid Personal Time (prorated upon hire with increasing accruals by tenure).

The company reserves the right to modify or change these benefits programs at any time, with or without notice.

For Los Angeles County (unincorporated) candidates: