Position NFTs

Every open position in EXNIHILO is represented as an ERC-721 NFT.

What the NFT holds

The PositionNFT contract custodies the locked wrapper tokens for the lifetime of the position:

Field	Long	Short
isLong	true	false
pool	Pool address	Pool address
lockedToken	airToken address	airUsd address
lockedAmount	airToken locked	airUsd locked
usdcIn	USDC position size	0
airUsdMinted	Synthetic debt	0
airTokenMinted	0	Synthetic debt
feesPaid	Open fees	Open fees
openedAt	Block timestamp	Block timestamp

Shared singleton

All pools share a single PositionNFT contract. Token IDs are sequential across all markets. The pool field in each position identifies which pool it belongs to.

ERC-721 Enumerable

PositionNFT inherits ERC721Enumerable, which means:

• balanceOf(address) — how many positions a user holds
• tokenOfOwnerByIndex(address, index) — iterate through a user's positions

The frontend uses this to populate the Portfolio page.

Collateral custody

The locked wrapper tokens (airToken for longs, airUsd for shorts) live in the PositionNFT contract, not in the pool. This provides clean separation — the pool's reserves and position collateral are physically separate.

When a position is settled, the pool calls release(tokenId), which:

1. Burns the NFT
2. Returns locked tokens to the pool
3. Returns the Position struct so the pool can complete settlement math