Baking Unlimited — a metered recipe-scaling SaaS for home bakers

What it is

A working Next.js 16 SaaS: a baker pastes a recipe, picks the pan they actually own, and gets every ingredient rescaled and rounded to something a kitchen can measure. Free keeps ten recipes and converts five a month; Pro is $9 a month for 300 conversions.

What is actually built

• The recipe shelf — a pasted recipe stored byte for byte with the pan it was written for. The free plan's ceiling returns 402 before the row is written, not after.
• The conversion — volumes computed from each pan's own dimensions, so the ratio between any two is exact. One conversion costs exactly one AI credit, and the cap is checked before the model runs rather than reported afterwards.
• Quantities a person can measure — whole eggs, quarter-sticks of butter, the ⅓ and ⅔ markings a cup has. 1.33 eggs is the failure this product exists to prevent, and there is a test that says so.
• Stripe plans — checkout, customer portal, idempotent webhooks, metered usage reported exactly once.
• Marketing — landing, pricing, /how-it-works, and a /pan-conversion-chart computed from the same catalogue the app scales with, so the chart cannot disagree with the product.

What is proven, and how

Every feature carries an acceptance spec that runs against a real database and a real server. At the last run: pnpm accept:all 18/18 green, pnpm test:e2e 60 passing, pnpm verify green with a Qlty maintainability grade of A, pnpm seo:check 444 assertions across 20 pages, and pnpm design:check 202 contrast assertions clearing WCAG AA in both light and dark.

What is not done

Stated plainly, because a buyer finding it later is worse than a buyer deciding now:

• /terms and /privacy need one field filled in. Both pages are written and registered noindex; entity, jurisdiction and processors are decided and recorded in PRODUCT.md. The contact address is deliberately left as REPLACE_ME@example.invalid — it is where a real deletion request has to arrive, and nobody can invent that for you. pnpm seo:check goes red on it the moment a real domain is configured.
• Billing and the AI run on built-in fakes. The wiring, the metering and the 402 are real and tested; no money moves until you create the $9 price at Stripe, and the baking notes are stock text until an LLM key is set. The arithmetic needs no keys at all.
• The deployed demo has no database. It is live on Vercel and the marketing pages work; every route that touches Postgres returns 500 until DATABASE_URL is set. Fifteen minutes with a managed Postgres fixes it.
• Kit surface is still in the dashboard — Projects, Chat, Documents and Organization are the starter kit's demonstration, not this product. Removing them is a rename of a published REST resource; PRODUCT.md records the measured cost.

Running it

pnpm install && pnpm run setup. No Docker, no accounts, no keys: every provider has a deterministic fake and Postgres runs embedded. pnpm db:seed --demo puts four recipes on the shelf to look at.

Licence

This is a licensed copy, not an exclusive sale. You are buying the right to use the codebase — change it, ship it, and sell whatever you build with it.