Jia Li

Ph.D. Student · Computer Science

Jia Li Linsay Li

The Chinese University of Hong Kong
Advised by Prof. Michael R. Lyu

I work on agentic software engineering — building and rigorously evaluating code agents that reason over entire repositories, diagnose failures, repair programs, and learn from real execution feedback.

Coding Agent Self-Evolving Software Systems Code Reasoning / Diagnosis / Repair Online Data Flywheel

My research connects code large language models with classical program analysis and reinforcement learning, spanning benchmarks, agentic systems, and training methods for real, repository-level, industrial-scale software. I was a research intern at WeChat, where several of these systems were deployed in production, and later at Tencent Hunyuan, working on post-training for long-horizon multi-turn agents. I am now with the Dots foundation model team at Xiaohongshu.

I study how code agents use program structure, combine evidence across files, and learn from execution feedback in real software systems.

1

Real Code

Program context

Give agents relevant program structure to guide code exploration and API testing.

MioHint

2

Real Reasoning

Evidence across files

Evaluate repository-level reasoning and connect code with runtime evidence to diagnose production failures.

RepoReasonHolmes

3

Real Reward

Learning from feedback

Use compilation, tests, and repair outcomes to evaluate patches and train agents with reinforcement learning.

ComBenchVulKeyGRPO Reshaping

My long-term goal is to build software agents that improve through use, learning from development, testing, and production feedback.

DevOps infinity loop: plan, code, build, test, release, deploy, operate, monitor
Feedback from development through production.
  1. Plan / Code Change context & program structure
  2. Build / Test Compilation errors & test feedback
  3. Operate / Monitor Crash scenes & runtime logs
  4. Feedback / Learn Repair outcomes & learnable reward

Next direction: turn sparse feedback from long-running software tasks into reliable training signals, and measure whether agents improve on new tasks.

First author on all listed works.

  1. GRPO signal reshaping architecture

    Signal Reshaping for GRPO in Weak-Feedback Agentic Code Repair

    Preprint

    38.5% → 53.5% compile-and-semantic accuracy

    GRPO training improves code repair over the base model's zero-shot result by learning from compilation and semantic feedback.

  2. Holmes retrieve-explore-reason architecture

    Holmes: Multimodal Agentic Diagnosis for Mixed-Language Mobile Crashes at Industrial Scale

    FSE 2026, Industry Track

    87.6% function-level localization accuracy
    ~40k production runs

    Diagnoses crashes in WeChat's mixed-language codebase by combining retrieval, code exploration, and runtime evidence.

  3. RepoReason benchmark architecture

    From Laboratory to Real-World Applications: Benchmarking Agentic Code Reasoning at the Repository Level

    ACL 2026 Main Oral

    Reveals gaps in reasoning across files.

    RepoReason tests whether code agents can combine evidence across a repository to verify program behavior.

  4. VulKey pattern-guided repair architecture

    VulKey: Automated Vulnerability Repair Guided by Domain-Specific Repair Patterns

    FSE 2026

    Improves repair accuracy on PrimeVul and Vul4J.

    Uses patterns from known vulnerabilities to guide LLM repairs across programming languages and models.

  5. MioHint LLM-assisted mutation architecture

    MioHint: LLM-Assisted Request Mutation for Whitebox REST API Testing

    ICSE 2026

    Guides API testing beyond coverage plateaus.

    Uses program structure to guide LLM-generated API requests when automated testing stops making progress.

  6. ComBench benchmark construction overview

    ComBench: A Repository-level Real-world Benchmark for Compilation Error Repair

    Preprint

    Exposes the gap between compilable and correct repairs.

    Reproduces real C/C++ compilation failures from GitHub CI to evaluate whether code agents produce correct patches.