ColorBreak

Public demo notice: the GitHub Pages deployment is a non-commercial demo. It does not have response-level anti-framing headers and must not be used for commercial transactions or financially consequential decisions. A production launch requires a header-capable static host/CDN.

Reproducible releases

Price snapshots are reviewed, committed release inputs. The Pages workflow verifies them but never regenerates them, so the deployed artifact is traceable to the commit and its release manifest. Refresh snapshots in a dedicated reviewed commit before release; the app withholds a buyer limit whenever its exact-printing snapshot is older than six hours.

ColorBreak is a mobile-first decision tool for Magic: The Gathering color breaks. Buyers can judge a live-auction bid in seconds; sellers can price a break against actual marketplace fees, product cost, and fulfillment.

Run locally

npm install
npm run dev

Production validation:

npm run check

npm run build creates dist/, including the committed static data needed by GitHub Pages.

Product model

• A break may contain multiple sealed products from multiple sets.
• Cards go to W/U/B/R/G/M/C/L by the printed color of the front face; lands always go to L.
• Market EV counts every exactly priced card. Sellable EV applies the user’s price threshold. Known EV is the priced lower bound when source data is incomplete.
• verified, estimated, and incomplete are confidence states. An incomplete result still produces a buyer verdict and outcome distribution from resolved data, with named warnings explaining what is missing and how the gap may affect the result.
• Seller fees are assessed per purchase. Packing and seller-covered shipping are assessed per shipment. Buyer-paid shipping is not seller revenue.

Data

• data/sealed/*.json: normalized MTGJSON sealed products and collation.
• data/corrections.json: narrowly scoped, sourced product corrections. This layer is authoritative over upstream sealed metadata.
• data/prices/*.json: a compact, timestamped Scryfall bulk-data snapshot containing only exact printings referenced by the normalized corpus. It is refreshed in a separately reviewed commit; deployment only verifies that committed input.
• There is no live-price repair path for picker or buyer eligibility. A snapshot miss remains a named, analysis-only blocker.
• tcgcsv: best-effort sealed market cost. The seller can always enter actual cost.

Unresolved contents and prices are surfaced as named omissions. For premium treatments on new releases, a missing treatment-specific market observation uses the same printing's listed TCG foil price and labels that basis; prices never cross printings or foil classes. Price-source availability is reported separately from product-content completeness, so a transient remote failure cannot make an otherwise exact product look structurally incomplete.

Structure

• src/domain/: pure valuation, marketplace, and legacy-link contracts.
• src/data/: source adapters and orchestration.
• src/App.tsx: buyer/seller task flows.
• tools/: offline data builders and validators.
• CONTEXT.md: domain language and product intent.
• SPEC.md: current acceptance contract.
• docs/release-runbook.md: canonical snapshot, release-posture, and audit procedure.

The app is a Vite static build and requires no backend or account.