Opening Lab

Strict chess opening memory training — Practice & Test modes, animated board, and £1.99 drill packs.

Stack

• React 19 + TypeScript + Vite 8
• TanStack Start / Router
• Tailwind CSS v4
• chess.js
• CBurnett piece SVGs (public/pieces/)

Pricing (GBP)

Tier	Price
Paid drill packs	£1.99
Opening Traps	6 lines free, then £1.99
Caro-Kann for Black	3 lines free, then £1.99
Scotch Gambit lessons	£2.99 (parked, not on sale)
Opening Lab+	£4.99 / month or £29.99 / year (not on sale)
Pay as you go	£1.99 per pack
Buy all	£10.99 one-time. Every drill pack now and any future drill packs. Not Lessons. Not a subscription. Not lifetime access.

Demo unlocks use localStorage (src/lib/unlocks.ts).

Email (welcome + purchases)

On Vercel, set RESEND_API_KEY so Opening Lab can send:

• Welcome after someone creates an email account
• Lab+ welcome after they subscribe
• Pack confirmation after they buy a pack

From: Opening Lab <[email protected]>.
Without the key the site still works; emails are skipped.

Optional fallback if you already have a mailbox: SMTP_HOST, SMTP_USER, SMTP_PASS.

Deploy to Vercel

One-click import (recommended):

https://vercel.com/new/clone?repository-url=https://github.com/TangoCash38/opening-lab

Or:

1. Open vercel.com/new
2. Import TangoCash38/opening-lab
3. Framework: Other / Vite (Nitro outputs .vercel/output via npm run build)
4. Build command: npm run build
5. Output: handled by the Nitro Vercel preset (no extra config needed)

CLI (if you have a token):

npx vercel login
npx vercel --prod

Project structure

src/
  components/opening-lab/
    app-shell.tsx       # Native-style header + views
    pack-list.tsx       # Packs, locks, prices
    unlock-modal.tsx    # Pay as you go / Lab+
    train-view.tsx      # Practice / Test
    chess-board.tsx     # Sliding pieces
    chess-pieces.tsx
    guide-view.tsx
    mini-board.tsx
  data/
    packs.ts            # Lines + isFree / isPremium / price
    pricing.ts          # £1.99 drill packs / lessons £2.99 / Lab+ £4.99 mo · £29.99 yr
  hooks/use-unlocks.ts
  lib/unlocks.ts
  routes/
  styles.css            # Tokens, board, touch CSS
public/
  pieces/
  manifest.webmanifest
  favicon.svg
  og.jpg

Create your own (web)

Website-only authoring: pick Black or White, play both sides on a Book board, then Remember this line. The locked SAN is stored in localStorage (src/lib/gym-line.ts) and trains with the same Practice → Test loop as a curated pack. Test unlocks after a clean Practice.

The authoring board shows a local opening chip (Italian Game · C50) from src/lib/opening-identity.ts — deepest SAN-from-start / FEN match, or Opening… when unknown. It never invents a pack name.

While authoring, the board POSTs /api/practice-review-eval (depth: 12, ~400ms debounce) and paints full Engine chrome: thin eval bar, MultiPV-2 rows, and soft green hints from each PV first move. Status copy is Engine · suggesting… only — never “SF cloud”, “Stockfish cloud”, or “Lichess”. Fail-soft { ok: false } hides the bar, MultiPV, and greens. Practice and Test never show Engine / MultiPV chrome.

The Remembered sheet body is the full line SAN, e.g. Remembered — 1.e4 e5 2.Nf3 Nc6 — locked as your gym line. Train it like a pack.

Play wrap hides this entry (!isPlayApp()).

Practice-review Engine (server)

POST /api/practice-review-eval is a short MultiPV-2 Engine eval (default depth 14, hard cap 16, wall ~2.5s). Create-your-own authoring reuses it at depth 12. Never mid-drill in Practice or Test.

Vercel has no Stockfish binary. Leave STOCKFISH_PATH unset on Vercel; the handler fail-softs { ok: false } (HTTP 200). Live eval comes later via a small worker that sets STOCKFISH_PATH (e.g. /usr/games/stockfish or /usr/bin/stockfish) and is reached as PRACTICE_REVIEW_EVAL_URL (same POST contract). Do not ship WASM Stockfish (or any GPL engine net) to the client or the Play WebView bundle.

Product copy should say Engine, not “Lichess / Stockfish cloud”.

Scripts

npm install
npm run dev        # 0.0.0.0:8080
npm run build
npm run typecheck

GitHub

https://github.com/TangoCash38/opening-lab

Google Play (Android)

The Play app is a raw System WebView (not Chrome TWA). Path B billing is one-time packs (pack_<pack_id_with_underscores>) and buy_all_packs via POST /api/play/subscribe and the Android Publisher products API. No Lab+. Set GOOGLE_PLAY_SERVICE_ACCOUNT_JSON on the host or subscribe returns 503 without granting. Project and build steps: android/README.md.