Jiaquan (Jack) Li
Berkeley, CA
669 [dash] 245 [dash] 0087 | li [dot] jack [dot] services [at] gmail [dot] com |
linkedin.com/in/jiaquan-li
|
github.com/iwnlcern
Education
University of California, Berkeley
B.A. Mathematics; Intended B.A. Computer Science (on leave; plan to return)
Aug 2024 - Jan 2026
GPA: 3.838/4.000
- Coursework (CS): Performance Analysis and Optimization of Computer Systems; Data Structures; Structure and Interpretation of Computer Programs
- Coursework (Math/Physics): Abstract Algebra; Differential Topology; Real Analysis; Honors Linear Algebra; Discrete Math; Calculus I/II/III; Quantum Mechanics I
Experience
polymr
Founding Engineer
San Francisco, CA
Jan 2026 - Present
- Built a C++23 planning engine and Python/FastAPI planner services for MRP, MRP II, DDMRP, and MPS, shipping deterministic JSON contracts and APIs for BOM explosion, vendor selection, capacity planning, routing optimization, release readiness, and scheduling.
- Built the startup's multi-tenant ERP backend in Bun/Express with tenant-scoped DB middleware, runtime SQL guards, schema migrations, real-time SSE flows, and backend support for planning, procurement, tracking, and assistant workflows.
- Delivered core production integrations including QuickBooks Online exports, OAuth/PKCE token flows, append-only job processing, Twilio/WhatsApp shop-floor workflows, and email/document ingestion pipelines for procurement operations.
- Built internal platform and automation infrastructure for autonomous development workflows, including a multi-repo control plane, isolated git worktrees, scheduler/repair loops, GitHub and Linear orchestration, review-environment leasing, deployment diagnostics, and evidence-backed validation.
California Partners for Advanced Transportation Technology (PATH)
Undergraduate Researcher
Berkeley, CA
Oct 2025 - Jan 2026
- Developing supervised and deep reinforcement learning lane-change policies in an in-house microscopic traffic simulator using Python and PyTorch.
- Defining state/action spaces and reward functions that trade off safety, comfort, and throughput; engineering trajectory features (relative speed, gaps, headway) from simulator logs with NumPy/pandas.
- Prototyping and evaluating supervised baselines and RL agents against collision rate, successful lane changes, and travel time across traffic densities.
Industrial Cyber-Physical Systems (iCyPhy)
Undergraduate Researcher
Berkeley, CA
Sept 2025 - Jan 2026
- Bridged Lingua Franca's deterministic reactor model with GameTime by generating per-reaction C and uC code and meta-CFGs to compute distributed worst-case execution time (WCET) bounds for distributed programs.
- Formally validated the LF to GameTime translation using KLEE symbolic execution over ~37k paths and more than 9 million symbolic instructions, ensuring functional equivalence between LF reactions and the transformed analysis model.
- Deployed ForkJoin, TCP, and MapReduce benchmarks on a 3-node FRDM-K64F and Zephyr testbed, measuring ~1 ms network RTT, ~6 ms LF runtime overhead, and WCET overestimates by ~23% compared to max observed execution time.
Projects
Berkeley, CA
Dec 2025
- Built an open-source C3 CLI password manager with SQLCipher-encrypted SQLite vaults; CRUD keyed by (site, username); multi-vault selection via --db-name/--db-path.
- Implemented secure UX primitives: echo-disabled password prompts, explicit zeroization of in-memory secrets after use, and cross-platform clipboard copy with timed auto-clear (10s).
- Stack: C3, SQLite/SQLCipher; OS clipboard utilities (pbcopy/xclip/clip).
San Francisco, CA
Oct 2025
- Built a real-time multi-room chat platform with an LLM assistant (Flask, Flask-SocketIO, SQLite), persisting history and surfacing snapshots for reconnecting users.
- Implemented JWT-based auth for protected WebSocket events, message persistence, and stop-generation controls; parsed SSE streams with httpx to chunk long AI responses and keep the UI responsive.
- Shipped the \"Find the AI\" social game: lobby codes, anonymized nicknames, auto-injected AI player, chat/vote timers, supermajority force-end, mute-on-elimination, and a reveal screen.
- Stack: Python (Flask, Flask-SocketIO, Flask-JWT-Extended, Flask-SQLAlchemy, Flask-CORS, Flask-Limiter, httpx), SQLite; JavaScript/Socket.IO client.
Berkeley, CA
Jul 2025 - Aug 2025
- Analyzed 50,000 Reddit posts; DST-aware UTC to US/Eastern conversion; derived time-of-day and weekday/weekend features; filtered noise ([removed], [deleted], very short texts).
- Built an NLP pipeline (TF-IDF 1-3 grams, Word2Vec bias axes, t-SNE) to compare lexical fields across temporal slices; visualized trends with matplotlib and interactive Bokeh.
- Stack: Python (pandas, NumPy, scikit-learn, gensim), matplotlib, Bokeh.
Publications
Formally Verified Worst-Case Execution Time Analysis of Distributed Lingua Franca Systems via GameTime
Zeynep Guzey, Anagha Ananth, Matthew Cai, Jiaquan Li
EECS Department, UC Berkeley
Fall 2025
Skills
Languages: Python, C++ (20/23), C, SQL, JavaScript/TypeScript, Java, C3
Backend & Systems: FastAPI, Express/Node.js, Bun, SQLite, PostgreSQL, Redis, SSE, WebSockets, multi-tenant SaaS architecture, background workers, job queues, webhook processing
AI & Agent Systems: LangGraph, LangChain, OpenAI API, Anthropic API, tool-calling agents, streaming LLM applications, checkpointed workflows, interrupt/resume flows
Infra & Tooling: AWS (EC2, ECR, SSM), Docker Compose, GitHub Actions, Git, Unix shell, systemd, CMake, Ninja, pybind11, OpenAPI, contract testing
Domain & Integrations: MRP/MRP II, DDMRP, MPS, QuickBooks Online, OAuth 2.0/PKCE, Twilio/WhatsApp, AgentMail, document pipelines
Data & ML: pandas, NumPy, SciPy, scikit-learn, PyTorch