# Yihao J.

> Research and Development at TikTok Ads.

Location: New York, New York, United States
Profile: https://flows.cv/yihaoj

Ph.D. in Computer Science with 5+ years of experience in large-scale systems and network security engineering. 

With a proven track record in designing and implementing foundational components for large-scale systems, I recently led the development of a cutting-edge "Zero Trust Network" security architecture, drawing inspiration from Google's BeyondCorp. This project achieved real-time, traffic-level authentication with ultra-low latency, robust performance, and minute-level fault recovery. Prior to that, I developed an adaptive network protocol for low-power electronics, resulting in a 5x increase in energy efficiency. This protocol is now integrated into HarmonyOS and deployed across millions of IoT devices globally.

As Artificial General Intelligence (AGI) approaches, I am committed to unlocking the transformative potential of Large Language Models (LLMs). My passion lies in pioneering Generative AI to redefine technological boundaries.

Let's connect to drive the next wave of innovation together.

## Work Experience
### Software Engineer @ TikTok
Jan 2025 – Present | New York City Metropolitan Area
Constructing the advertisment platform and system.

### Generative AI Engineer @ Buysmart.ai
Jan 2024 – Jan 2024 | Mountain View, California, United States
Built a shopping AI agent for E-commerce recommendations using Large Language Models (LLM) and OpenAI function-call.

- Optimized embedding-based Retrieval-Augmented Generation (RAG) with Milvus vector database by integrating 1) synthetic merchandise review with expert transcripts and 2) query rewrite via Chain-of-Thought (CoT), boosting F1 score by 37%.

- Constructed an evaluation system to score workflow traces based on context relevance (RAG eval.) and answer accuracy (LLM eval.), leading to continuous prompt refinement and a 36% increase in Click-Through Rate (CTR).

- Developed a security monitoring platform for prompt injection detection, enabling real-time intercepts for data exfiltration.

### Senior Engineer @ Xiaohongshu
Jan 2022 – Jan 2023 | Shanghai, China
• Led the infrastructure security team in constructing a comprehensive cloud-native security system with Scrum agile mode.

• Derived a zero trust architecture from 0 to 1 across the entire enterprise, spanning multiple clouds and on-premises networks.

• Enabled hierarchical fault-tolerance with Raft algorithm using gRPC, enabling end-to-end error detection and auto-recovery.

• Implemented a unified authentication module in the L7 load balancer (reverse proxy), maintaining ≤ 10ms additional latency scaling 10x hot-pluggable rules (coordinated via Redis) across peak traffic of 100k QPS.

• Deployed services in AWS EC2 and serverless Lambda with Terraform, achieving auto-scaling for 1k-100k fluctuating.

• Protected 1k+ services by identifying and mitigating 100+ threats monthly, achieving a NPS of 80 among 10k+ users.

### Senior Research Engineer @ Huawei
Jan 2019 – Jan 2022 | Beijing, China
IP 技术预研与技术标准化


## Education
### Master's degree in Electrical and Computer Engineering
Carnegie Mellon University

### Doctor of Philosophy (Ph.D.) in Computer Science
Tsinghua University

### Visiting Scholar in Computer Science
Northwestern University

### Bachelor of Engineering - BE in Electrical and Electronics Engineering
University of Electronic Science and Technology of China

### Exchange Student in Information Engineering
National Taiwan University of Science and Technology


## Contact & Social
- LinkedIn: https://linkedin.com/in/yhjia
- Website: https://app.codesignal.com/evaluation-result/j29EY3kNp7mv5q4Kz?accessToken=ahGng7Awp5n2ZNRrd-cgFHgFyHcu4tvHRnSqP8EjbM

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Source: https://flows.cv/yihaoj
JSON Resume: https://flows.cv/yihaoj/resume.json
Last updated: 2026-04-05