01
Define a community need
Set quantities and a spending ceiling for an essential-goods basket. The app never receives or moves donated funds.
✳ WEB3 FOR SOCIAL GOOD · WORKING PROTOTYPE
Spend wisely.
Prove every decision.
A clearer way for community kitchens and small nonprofits to compare essential-goods offers, document the choice, and keep a tamper-evident audit trail — without ever taking custody of donations.
✓ Direct product links✓ Price-source labels✓ No funds held by the app
A narrow problem, a practical workflow
From a shopping list to accountable evidence.
Community buyers often compare the same essentials with limited time and tight budgets. FairBasket keeps the offer, source, decision and evidence connected — so a reviewer can inspect the process instead of relying on a spreadsheet alone.
02
Compare actual offers
Reuse Onde compro? search to find direct product pages. Distinguish listing/API values, product-page metadata, published ranges and unverified search snippets.
03
Preserve the evidence
Generate a SHA-256 digest for each evidence record, export the audit bundle, and optionally anchor the digest on Base Sepolia with a wallet-signed transaction.
What the pilot will measureThese are evaluation metrics, not reported outcomes. We will measure them with a partner pilot only after consent.
Cost per kitCompare like-for-like product totals before checkout.
Time to compareMeasure minutes from needs list to documented decision.
Evidence coverageShare of line items with a source and reproducible record.
Try the prototype
Compare the basket. Keep the evidence.
Start with a fictional pantry, search for real product pages, link offers to a need, and create records you can export or anchor on a testnet. Search results depend on the available search-provider configuration.
01 · Community purchase plan
Illustrative scenario · no real organisation or spend
Community Kitchen Esperança
20 essential-goods kits · Brazil · monthly planning cycle
Fictional name and figures for demo use only.
Budget capR$ 2.400,00
Basket projectionR$ 1.967,60
Items with exact-source prices0 / 8
Exact-source subtotalR$ 0,00
Difference vs. demo values—Not realised savings
Illustrative plan82% of ceiling
Important: the values below are made-up planning references to demonstrate the workflow. They are not current market prices, quotations or purchases. Only an offer from the search API marked as exact can replace a planning value as a verified quote.
The snapshot is hashed in this browser. Exported JSON lets a reviewer inspect the payload and reproduce its digest.
02 · Search & compare an offer
Find a direct product page for one need.
Fallback for the demo only. These are not actual offers or prices.
Choose a need and search to load offers from Onde compro?.
Source discipline: a number found in an indexed text snippet is a reference, not a live-confirmed price. Freight, variant, stock and checkout can change the final total.
03 · Evidence log
Records created from the workflow in this browser.
No evidence yet. Search for an offer or create a plan snapshot to generate the first digest.
Nothing has been anchored on-chain yet. Local hashes alone are not a blockchain record.
04 · Web3 accountability layer
Anchor a digest on Base Sepolia
Wallet-signed testnet transaction · no purchase funds move through this app.
Demo mode. Connect a wallet, switch to Base Sepolia and provide a deployed contract address to write a real testnet transaction.
Only hashes, a public campaign identifier and the declared amount/type are written on-chain. Never put names, addresses, private donation details or unredacted receipts in public evidence payloads.
- Install or open an EVM wallet such as MetaMask. Use a dedicated test wallet, not a wallet holding valuable assets.
- Click Deploy test registry. The browser downloads the compiled FairBasketRegistry artifact from this site; confirm the deployment in your wallet.
- After deployment, click Create plan snapshot or save a product-source record. Select that record in the evidence log.
- Click Publish on Base Sepolia. On first use, the wallet asks to register the demo campaign and anchor the record. Approve both only if the wallet shows Base Sepolia (chain ID 84532).
This prototype never requests a seed phrase or private key. Deploying and anchoring requires testnet ETH for gas; transactions are not sent to mainnet. If the compiled artifact is unavailable, use Remix IDE and the contract source.
Official Base chain-ID documentation ↗Trust by design
Web3 is a verification layer, not a buzzword.
The product remains useful if nobody connects a wallet. A testnet transaction is an optional tamper-evident anchor, not a claim that the source price is correct or that delivery occurred.
Evidence stays inspectable
Each record exports its payload, source link, timestamp and digest. Reviewers can reproduce the SHA-256 hash as well as check any on-chain transaction.
Privacy before publicity
Personal details and unredacted receipts do not belong on a public chain. The contract stores a digest, type and declared amount only; the source record is reviewed separately.
Impact claims are measurable
We do not claim savings, partner adoption or deliveries from fictional data. A pilot will measure comparable line-item costs, comparison time and evidence coverage.