
Zanwen Fu
Machine Learning Engineer (Agentic) at Robinhood · M.S. CS at Duke
Agents that survive production.
I build agent systems that hold up in production, not just in demos. The model is the easy part; the harness around it is where I spend my time.
About
My work lives in the layer between a capable model and a product people can actually rely on: orchestration, evaluation, rollback.
The clearest proof is VYNN AI (opens in new tab), an agentic financial analyst I designed and built alone: a LangGraph multi-agent backend, a FastAPI orchestration layer, and a React dashboard, about 50K lines in all. It ran a ~500-user pilot and is now back online (opens in new tab), serving 5,000+ users.
Before that I was a research engineer on AutoCodeRover (opens in new tab), an autonomous code-repair system whose core technology was acquired by Sonar; my pieces were the JetBrains plugin and the Self-Fix retry loop that pushed its SWE-bench Verified score to 51.6%. Alongside it I led research as first author on LUMINA (opens in new tab), a multi-agent framework for medical citation screening that reached 98.2% mean sensitivity across 15 systematic reviews.
The thread through all of it is the harness, and that obsession now has a repository: taste (opens in new tab), an open-source operating system for agents that treats git as the memory substrate.
I'm spending summer 2026 at Robinhood in Menlo Park, on the Agentic AI team. I'm open to full-time roles starting 2027.
Duke University
2025 – 2027
M.S. Computer Science (AI/ML) · Graduate Teaching Assistant · scholar profile (opens in new tab)
National University of Singapore
2021 – 2025
B.Comp. in Computer Science (Honours, Distinction) · Distinction in Software Engineering (opens in new tab) · exchange at HKU, Fall 2023
Experience
current · May 2026 – Aug 2026
Machine Learning Engineer (Agentic) · Menlo Park, CA
Agent reliability and evaluation — the infrastructure layer that lets Robinhood ship AI into a regulated financial domain. Kafka-based news and market-data pipelines, Braintrust-driven evals, and post-training workflows (SFT on Databricks) spanning closed-source (GPT-4.1) and open-source models.
Python · OpenAI Agent SDK · Braintrust · Kubernetes · Kafka · Databricks · SFT
Jul 2025 – Dec 2025
Founder & Software Engineer (Agentic) · Durham, NC
Built and ran a full-stack agentic financial analysis platform solo: LangGraph multi-agent backend, FastAPI orchestration layer, React dashboard, and production infrastructure on Hetzner Cloud. The pilot served ~500 users with full equity research (DCF modeling, news intelligence, automated reports) in under 7 minutes end-to-end; the product is live again and has grown to 5,000+ users.
Python · LangGraph · FastAPI · React · TypeScript · MongoDB · Redis · Kafka · Docker · Hetzner
Aug 2025 – Apr 2026
Graduate Teaching Assistant · Durham, NC
Designed and ran CS 590 (Software Development Studio), where graduate students build AI debugging agents inspired by AutoCodeRover and deploy full-stack applications. Mentored teams in CS 408 and CS 390 on software architecture, DevOps, and LLM-oriented programming, shipping production software for outside clients.
Python · Docker · CI/CD · Git/GitLab · Web Assembly
Aug 2024 – May 2025
Research Engineer · Singapore
Built the JetBrains IDE plugin end-to-end for autonomous code repair: GumTree-based 3-way AST merge, embedded SonarLint analysis, and real-time SSE streaming with per-step developer feedback. On the backend, added LLM-as-a-Judge self-improvement that lifted SWE-bench Verified to 51.6%, state-of-the-art among open-source agents at the time. The core technology was acquired by Sonar.
Kotlin · Python · IntelliJ Platform SDK · GumTree · SonarLint · JGit · OkHttp
Jul 2025 – Oct 2025
Software Engineer · Singapore
Built backend validation infrastructure for Binance's Boosters campaign — automated API regression suites in CI, load-tested services to ~500K concurrent transactions via JMeter, and instrumented monitoring to catch consistency failures before production.
Java · REST APIs · iOS · Android SDKs · Postman · JMeter · CI/CD
Jan 2024 – Jul 2025
AI Researcher · Singapore
Led research as first author on a multi-agent AI framework for medical evidence synthesis. Designed and built LUMINA, a four-agent LLM framework that automates citation screening for medical systematic reviews — achieving 98.2% sensitivity and 87.9% specificity across 15 SRMAs (~150K citations) with a 35× reduction in false negatives vs. prior state-of-the-art.
Python · LangChain · CI/CD · GPT-4o-mini · GPT-o3-mini
Earlier
Full-Stack Software Engineer · ST Engineering
May 2023 – Aug 2023
Quantum Software Engineer · Centre for Quantum Technologies (Singapore)
May 2024 – Dec 2024
Research Assistant · NUS Computing
Feb 2024 – Nov 2024
Selected work
VYNN AI
2025 · founder & sole engineer
Give it a ticker; get the report an equity analyst spends a day writing, in about seven minutes.
A LangGraph supervisor orchestrates seven agents: fundamentals, news intelligence, DCF valuation, and a three-layer recommendation engine in which the LLM never invents a number. I built all of it, about 50K lines across backend, orchestration, and frontend, and ran a ~500-user pilot on production infrastructure. It's back online now, free for everyone, and past 5,000 users.
app.vynnai.com (opens in new tab)·Architecture deep-dive·GitHub (opens in new tab)·Blog post
AutoCodeRover
2024 – 25 · research engineer · acquired by Sonar
Autonomous code repair, from research prototype to acquired product.
I built the JetBrains plugin end-to-end, including a GumTree three-way AST merge that reconciles concurrent edits Git fundamentally can't, and the Self-Fix Agent that helped lift SWE-bench Verified from 38.4% to 51.6%. The core technology was acquired by Sonar. Their Foundation Agent, built on it, later reached 79.2%, top of the leaderboard at the February 2026 announcement.
Architecture deep-dive·ISSTA '24 paper (opens in new tab)·GitHub (opens in new tab)·Blog post
taste
2026 · open source · building
An operating system for agents, with git as the memory substrate.
Branches are execution contexts, commits are checkpoints, git reset --hard is rollback, and worktrees give parallel workers real filesystem isolation. v0 is shipped: three demos with committed transcripts, full cost telemetry, and CI-asserted hermetic rollback. The design argument is in the blog; the repo is the implementation.
Architecture deep-dive·GitHub (opens in new tab)·Design thesis
LUMINA
2024 – 25 · first author · submitted to NEJM AI
A four-agent framework that screens citations for medical systematic reviews the way human reviewers do.
Classifier, PICOS-guided screener, LLM-as-a-judge reviewer, and a self-correcting improvement loop. Across 15 published reviews and roughly 150,000 citations it reached 98.2% mean sensitivity with 87.9% specificity, a 35× reduction in missed studies against prior published baselines, at under a cent per article.
Writing
Beyond the Harness: An Operating System for AI Agents
Mar 2026
Why the industry's biggest problem isn't the model — it's the infrastructure. And why git, not markdown, should be the memory layer.
From Research Agent to Acquired Product: What I Learned Building the AutoCodeRover IDE Plugin
Mar 2026
How I turned an academic code repair agent into a developer tool, built a self-correcting feedback loop, and designed an AST-level patch merge system that Git can't do.
Building VYNN AI: 50,000 Lines of Code, One Engineer, and Everything I Learned
Mar 2026
How I built and scaled an agentic financial analysis pipeline from scratch, handling complex graph routing, deterministic validations, and real users.
Teaching
Graduate TA at Duke CS. Across three courses I've run the hands-on infrastructure side: 48 students across 15 teams shipping systems with Docker, CI/CD, and AI agents, on labs and benchmarks I build and maintain.
Spring 2026
Graduate course covering production software engineering, Docker, CI/CD, API design, and server deployment — culminating in students building an AI debugging agent (inspired by AutoCodeRover) and a full-stack social media application.
Mentoring teams on architecture, testing, DevOps, and full-stack development to deliver production-ready software for outside clients.
Fall 2025
Leading weekly labs covering AI agents, LLM-oriented programming, Docker, APIs, and system design.