YGO Compare

Free Yu-Gi-Oh! TCG price comparison: cards worth a dollar or more (in any printing), every card from new sets, and every sealed product, compared across TCGplayer, eBay and Yu-Gi-Oh! game stores (US, UK, Canada, Australia, EU), updated daily.

Built on the Rift Compare playbook (riftcompare.com, repo Specifxx/TCGEmpire), on the lean engine shared with Gundam Compare and Lorcana Compare. The only game-specific files are src/site.config.ts and src/content/ (stores, blog posts, pre-order copy).

How it works

GitHub Actions, daily 12:17 UTC (refresh-prices.yml)
  TCGCSV (TCGplayer catalogue + prices, category 2; cards under $1 left out)
  + every Shopify store in src/content/stores.ts  (products.json)
  + eBay Browse API, budgeted (2,200 calls/day, cards from $20, all sealed)
  → data/public/*.json, data/history/<set>.json, data/state/*.json
  → commit to main with "[deploy]" in the subject  → one Vercel build a day
  → IndexNow ping

• Public pages never touch the database. They read the committed JSON (src/lib/data.ts), shipped with the deployment. Pages revalidate every 6–24 hours and card pages are cached on first visit (nothing prerendered at build).
• There is no database. No accounts, no Premium, no email: the site compares prices and earns through affiliate links (eBay, TCGplayer, Amazon).
• Deploys are gated (scripts/vercel-ignore-build.sh): production builds only when the commit subject has [deploy]; previews need [preview]; claude/* branches never deploy.

Features

Card and sealed pages with a price row per store (cheapest in-stock first, affiliate buy links through /go, each click a Vercel buy_click event), price history charts, set price guides, movers, a pre-order tracker, guides with live price tables, and free tools: Deal Finder, Rising Cards, Demand Finder, Best Basket, a trade calculator and a selling-fee calculator. Dark theme by default with a light toggle, and a Halloween theme that switches itself off at the visitor's midnight on 31 October.

Yu-Gi-Oh!-specific matching: card numbers like RA01-EN008 (the language is part of the number, so German or Asian-English copies never match), a store title that names a rarity must name the card's own (one number can exist in six rarities), and 1st Edition / Unlimited is read from the title or variant, never guessed.

Finding stores: .github/workflows/probe-stores.yml checks every candidate in research/candidate-hosts.txt for Yu-Gi-Oh! collections and prints a stores.ts listing to review.

Run locally

npm install
cp .env.example .env
npx tsx scripts/import-all.ts   # fetch data (EBAY_REFRESH=false to skip eBay)
npm run dev

Checks: npm run typecheck, npm run lint, npm test.

Going live

See docs/SETUP.md (and the Claude in Chrome prompt in docs/CHROME-SETUP-PROMPT.md).