Jiyu Liu 刘骥宇
Distributed Database Engineering · High-Performance C++ · Computational Mathematics
Profile
Systems engineer with doctoral research experience in computational mathematics. Built distributed query-execution and profiling capabilities in a production MPP engine, alongside fourth-order C++ finite-volume and multigrid solvers for complex geometries.
Experience
Tencent · Distributed Database Engineering Intern · Qingyun Program
Jul 2025 — Jul 2026- Extended an MPP execution engine with two-stage aggregation and distributed-plan support for complex subqueries; resolved intermediate- state merging, data redistribution, and cross-node semantic-consistency issues.
- Built a distributed query-profiling path that connects frontend, planner/optimizer, and worker metrics into query, operator, node, and thread views; added operator-boundary inspection for complex-plan debugging.
- Identified lock contention caused by high-frequency instrumentation in a large analytical benchmark and moved collection to operator boundaries to keep diagnostic overhead under control.
Hangzhou Higgs Investment Management Co., Ltd. · Full-Stack Strategy Engineer
Nov 2024 — Jun 2025- Built high-frequency market-data storage and real-time subscription pipelines with C++/Python, SQLite, and TDengine, supporting concurrent access from multiple threads and processes.
- Integrated brokerage market-data APIs and delivered trading-monitoring and live-parameter query tools for research and operational workflows.
- Prototyped a local document and natural-language SQL assistant with LightRAG, Vanna AI, DeepSeek, and Streamlit for internal troubleshooting.
Selected Research
Fourth-Order Cut-Cell Multigrid Solvers
Researcher · Co-first authorA modular C++ framework for high-order finite-volume discretization and geometric multigrid on irregular embedded boundaries.
- Approximately fourth-order convergence across multiple complex geometries
- Near-optimal complexity for the boundary-value solver under grid refinement
High-Fidelity Solvers for Density-Stratified Flows
Researcher and C++ developerA high-order finite-volume solver for density-stratified incompressible flows under the Boussinesq approximation, including irregular and moving boundaries.
- Fourth-order accuracy in space and time for manufactured-solution studies
- Numerical results consistent with reference experiments
Education
Zhejiang University · Direct-track doctoral student in Computational Mathematics
Sep 2021 — Expected Mar 2027GPA 92/100 · Doctoral degree not yet awarded · Research focus in high-performance numerical computing, finite-volume methods, and multigrid solvers
Zhejiang University · B.S. in Information and Computing Science
2017 — 2021Overall GPA 4.38/5.00; final two years 4.78/5.00 · Outstanding Graduate (Top 5%) and First-Class Scholarship (Top 2%)
Technical Scope
Production systems: C++ (STL, modern C++, concurrency, resource lifetime); Python and SQL; Linux, Git, CMake, GDB; SQL execution engine and query optimizer internals; MPP execution, data exchange and pipeline scheduling; TPC-H, TPC-DS, MTR, profiling and regression analysis
Scientific computing: Numerical PDEs and finite-volume methods; Geometric multigrid and sparse linear algebra; OpenMP, Eigen, LAPACK / MKL; HDF5 / Silo data workflows; Accuracy, convergence and complexity studies
Data infrastructure: SQLite and TDengine; Concurrent ingestion and real-time subscription; Brokerage market-data API integration; LightRAG, Vanna AI and Streamlit prototypes
Honors
Zhejiang University Outstanding Graduate · Top 5% · Zhejiang University First-Class Scholarship · Top 2% · CASC Second-Class Scholarship · Outstanding Graduate Student and Outstanding Graduate Student Leader · Guoxiang Scholarship and Freshman Excellence Scholarship