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Case study 01 / Product

Make a daily check-in verifiable.

Cookie Checkpoint turns a simple streak habit into a real, inspectable Cookie Chain transaction without asking users to trust a private database.

Role
Product design and full-stack implementation
Stack
React, TypeScript, wallet APIs, Cookie Chain RPC
Proof
Each completed checkpoint links to Cookiescan

Challenge

The experience needed to feel as quick as a normal daily check-in while still producing a verifiable on-chain record. It also needed to work with Nightly on Cookie Chain without collecting seed phrases or private keys.

What I built

  • Nightly wallet detection and connection through the standard Solana wallet interface.
  • Network checks before the user is asked to approve a transaction.
  • COOK balance, current slot, and recent-signature reads from the Cookie Chain RPC.
  • A zero-value self-transfer with a readable Memo Program payload, followed by confirmation and a Cookiescan link.
  • A local streak trail in browser storage while keeping the signed checkpoint itself public and verifiable.

Result

The result is a lightweight product demo where the meaningful action is not just a UI state: every completed checkpoint can be inspected on the network. The implementation keeps the transaction model simple and makes wallet safety and network clarity visible in the flow.