6 · Smart‑Contract Design

Minimal‑surface principle — each contract does one job; single‑hop internal calls.

6.1 PADToken

BEP‑20 + EIP‑2612 Permit, BatchTransfer. Pausable; TimelockRole for emergency.

6.2 StakeManager

Packed struct (amount | start | duration | tier). weeklyRate = rewardsPool / totalStaked * 52. 72 h cooldown prevents flash‑stake loops; max 5 active positions per address.

6.3 PADNFTFactory

mintSBT() (on‑chain SVG) & mintPass() (ERC‑721A). Tier upgrade burns old NFT, mints new.

6.4 Treasury

Gnosis Safe 3/5 (3 core keys + 2 community after 12 m). BuyBack module swaps PAD/BNB on PancakeSwap v3 then burns PAD.

Operation	Gas	USD (5 gwei)
stake 1 000 PAD	142 205	$0.07
claimRewards	92 887	$0.05
mintPlatinumNFT	121 006	$0.06