Software Engineer - TikTok AI Search Infrastructure

Responsibilities

About the Team
TikTok AI Search Infra team is responsible for building highly performant, scalable and stable infrastructures that serve billions of search requests everyday, and reinventing the search experience of billions of users globally. We apply cutting edge ML/NLP/LLM/VLM technology for end-to-end modeling, and focus on building and optimizing performance/efficiency for large-scale ML infra and online/offline distributed systems, enabling AI to realize its potential value for billions of TikTok users. We embrace a culture of self-direction, intellectual curiosity, openness, and problem-solving.

Responsibilities
- Evolve TikTok's AI Search multi-agent LLM engine, supporting ReAct + Tool calling, DAG-based workflows, and RAG paradigms
- Deploy and optimize text/multimodal LLMs, including inference acceleration, model alignment during training, and reinforcement learning
- Build scalable and reliable end-to-end serving platforms supporting multiple TikTok AI Search use cases, such as Q&A cards, in-app chatbot, and visual search, including both online and offline scenarios
- Build large-scale data architecture for handling billion-level data records: offline computation, distributed system performance and scheduling optimization, as well as building high-availability, high-throughput, and low-latency online services
- Design and build personalized AI search capabilities to achieve more accurate AI Overview and Q&A experience for users
- Collaborate with modeling and product teams to deliver better AI search experience for Tiktok users

Qualifications

Minimum Qualifications:
- Bachelor or advanced degree in Computer Science or related disciplines
- At least 5 years of industry experience in one of the following areas: recommendation, search, Ads and ML Infra
- Strong Computer Science background, proficient coding skills and solid understanding of algorithm & data structure.
- Have experience in at least one of the following areas: recommendation system, search engine, advertising engine, Agent/RAG engine, LLM serving/training.
- Effective communication and teamwork skills, strong ownership mindset

Preferred Qualifications:
- Familiar with system performance optimization in Linux environment, experience with large-scale C++ system development are preferred
- Familiar with large-scale distributed systems development; experience with distributed databases or distributed data processing frameworks is a plus
- Experience with GPU inference optimization, LLM/VLM serving and training are preferred

Job Information

[For Pay Transparency] Compensation Description (annually)

The base salary range for this position in the selected city is $244800 - $588000 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:

Qualified applicants with arrest or conviction records will be considered for employment in accordance with all federal, state, and local laws including the Los Angeles County Fair Chance Ordinance for Employers and the California Fair Chance Act. Our company believes that criminal history may have a direct, adverse and negative relationship on the following job duties, potentially resulting in the withdrawal of the conditional offer of employment:

1. Interacting and occasionally having unsupervised contact with internal/external clients and/or colleagues;

2. Appropriately handling and managing confidential information including proprietary and trade secret information and access to information technology systems; and

3. Exercising sound judgment.