Projects & tools
Most of these run on their own subdomain as independent Workers. Some work, some are still being built.
SweetValueLab
Equity research your Claude can use. Connect it as an MCP server, then research stocks, paper-trade and review your portfolio in one conversation. Free tools include a portfolio backtester and a FIRE calculator.
US Equity Research
My own equity research, one interactive page per company: sum-of-the-parts valuations, earnings breakdowns, what you have to believe, and the risks. Starts with SpaceX.
The Debate Arena
Critical-thinking practice for kids aged 5 to 12. 25 questions with no right answer, an AI opponent that argues back, and an audience of 20 that only moves for good reasons.
Mahjong AI, from zero to playing
A learning project with a 16-chapter tutorial: write a Mahjong engine, a rule-based bot, train a network to imitate it by supervised learning, then beat it with PPO. Includes a full Riichi Mahjong engine.
System Design Notes
My system design interview notes: eight classic problems (Ticketmaster, Uber, Web Crawler, TinyURL and more) written as the questions an interviewer asks and the answers I'd give.
IELTS Notes
IELTS study notes in Chinese: speaking topics with model answers and General Training writing samples for every letter type and common Task 2 theme.
How to FIRE
An open-source book in Chinese on financial independence for ordinary people: how wealth compounds, the tools available, and how to build a system. Still being written.