Projects
Things I've designed, built, and kept running.
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Live · tailorcards.com
Tailor Cards Website
A live e-commerce site taking real orders. JPA optimistic locking and stock re-checks stop one-of-a-kind cards selling twice; TOTP two-factor admin login, account lockout, CSP/HSTS headers and an append-only audit log; 450+ tests run on every pull request.
java 21 · spring boot · react · typescript · postgresql · stripe · github actions
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Private beta
AI Buylist Assistant
An LLM assistant that takes up to 1,000 items: the model identifies cards, Java prices them. Matching for a 60-item list went from 35.3 s to 16.6 s, guarded by a benchmark that fails the build on regressions. Model-emitted prices are rejected server-side to block prompt injection, with rate and spend limits and a weekly LLM evaluation in CI.
java 21 · spring boot · claude api (tool use) · rest apis
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Data · AWS
Tailor Cards Data Pipeline & Analytics
An automated AWS ETL pipeline (Lambda, EventBridge) that loads daily market prices into date-partitioned S3, with 10 data-quality checks (oversold stock, orphan records, price spikes) and 85 tests run in CI, feeding a Tableau dashboard.
python · sql · aws lambda · s3 · glue · athena · tableau
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Live · interactive data story
Are Prediction Markets Calibrated?
When a market says 70%, does it happen 70% of the time? An interactive data story on 46,168 resolved Kalshi and Polymarket markets: a 60-second scroll-through of the whole study, real upsets (sure things that lost, long shots that won), a guess-the-odds game and a $100 betting simulator.
python · statistics · sql (duckdb) · d3.js · github actions