YGG· Waifu SweeperFrontend & Contract Engineer

Problem · The token economy (reward multipliers, repurchase incentives, seasonal events) changed weekly, and every touch of the payment contract put user funds at risk.

• ShopManager, NFT, and PriceFeed run behind UUPS proxies with a storage layout review fixed into the deploy checklist. New capabilities such as the session tracker live in separate contracts rather than new proxy slots.
• Game rules, entities, and reward logic specified through context injection so in-game logic changes ship quickly and consistently.
• Result: 19,939 payments with no failures and weekly design releases.

Problem · Repeated actions such as opening tiles, defeating monsters, finding items, and reviving had to be recorded on-chain without a wallet signature every time.

• A hook that creates, stores, and restores a 24-hour session key with a fee limit and per-contract, per-selector call policies.
• A WaifuGameSessionTracker contract that validates ordering with a per-player session id and action nonce.
• Passed the tracker address as an argument instead of adding storage to the already-deployed ShopManager proxy (storage layout safety), and documented why.

• ShopManager (UUPS): ETH/USDC/USDT/YGG payments with explicit per-token decimals, EIP-712 signature verification with nonce replay protection, slippage handling.
• PriceFeed (UUPS): Pyth ETH/USD feed, confidence checks, cent-denominated pack pricing.
• WaifuSweeperNFT (UUPS ERC721): batch minting up to 30, paginated tokensOfOwner to stay under gas limits.
• Client: bundles Pyth price updates into the transaction, NFT as a payment method, YGG discounts.

• Season and Gold Mine leaderboards, reward dashboard, revive mode, referral-code validation.
• Maintenance page with a service schedule, per-feature and date-based flags.
• GA4 event design, Twitter Pixel, SEO/OG, BGM and sound effects, image preloading.