When Deavyn, Dhaniel, Jayda, and Mhar walked into their senior capstone, none of them had ever written a line of Solidity, deployed a smart contract, or used a Web3 wallet. Four months later — with mentorship from Pūpūkahi Tech — they presented Hawaii Coffee Provenance: a blockchain-backed traceability app that follows Hawaiʻi-grown coffee from the farm all the way to the cup.
The problem: 'Kona Coffee' that isn't
Hawaiʻi coffee farmers face a real and persistent problem: under current state law, a bag can be labeled 'Kona Coffee' even if it contains as little as 10% Kona beans. The other 90% can come from anywhere. That practice erodes consumer trust, deflates prices for farmers doing it right, and chips away at one of Hawaiʻi's most iconic agricultural brands.
The capstone team set out to fix that with technology — using an immutable ledger to prove, batch by batch, exactly where each pound of coffee actually came from.
From zero to smart-contract developers in four months
Pūpūkahi Tech mentors worked alongside the team from day one. We started with the absolute basics — what a blockchain is, why immutability matters, how a wallet signs a transaction — and worked up to deploying their own Solidity smart contract on a testnet.
Within weeks, the students were writing their own contract functions to register batches, transfer custody between farm, mill, roaster, and retailer, and enforce role-based permissions so only authorized parties could update a record.
They also built a simple app to go with it. A shopper can pick up a bag of coffee at the store, scan the little square QR code on the label with their phone, and instantly see exactly where those beans came from — which farm grew them, who roasted them, and every stop they made along the way before reaching the shelf.
What they shipped
By presentation day, Hawaii Coffee Provenance included an immutable batch registry stored on-chain with supporting media on IPFS, a QR-code generator that links each physical bag to its on-chain record, role-based permissions for farmers, processors, and retailers, and a consumer-facing lookup page that surfaces the entire provenance trail in seconds.
Not bad for a team that, sixteen weeks earlier, had never touched Web3.
Why this matters for Hawaiʻi
This is exactly the future Pūpūkahi Tech is here to build: kamaʻāina students using emerging technology to solve real problems for Hawaiʻi industries — and graduating with the kind of resume that lets them stay in the islands while doing world-class work.
Outcomes
- ›Four CS students with no prior blockchain experience shipped a working smart contract in 4 months
- ›Live React + Web3 app traces Hawaiʻi coffee from farm to cup via QR code
- ›Capstone presented at the UH Mānoa Department of Information & Computer Sciences
- ›Team gained industry-relevant Web3 skills and a portfolio-ready project
