Architecture Overview

EXNIHILO consists of five smart contracts working together.

Contract hierarchy

EXNIHILOFactory (singleton, immutable, no owner)
  │
  ├── Per market deployment:
  │   ├── AirToken (airToken — wraps underlying ERC-20)
  │   ├── AirToken (airUsd — wraps USDC)
  │   └── EXNIHILOPool (AMM + trading engine)
  │
  ├── LpNFT (singleton — one token per pool)
  └── PositionNFT (singleton — all positions across all pools)

Contracts

EXNIHILOFactory

The entry point for market creation. Fully permissionless — anyone can call createMarket(). No admin functions, no owner, all parameters are immutable after deployment.

Deploys AirTokens + Pool, mints LP NFT, seeds initial liquidity — all in one atomic transaction.

EXNIHILOPool

The core contract. Handles:

• Token swaps (SWAP-1)
• Long/short position opens (SWAP-2, SWAP-3)
• Position closes and realizes
• Liquidity management (add/withdraw)
• Fee accounting and claims
• Position cap enforcement

All state-changing functions are protected by ReentrancyGuard and follow the CEI pattern.

AirToken

Minimal ERC-20 wrapper. Deployed twice per market. Only the owning pool can mint/burn. The factory wires it to the pool via initPool() (one-shot, irreversible).

PositionNFT

Shared ERC-721 Enumerable contract. Custodies locked wrapper tokens for all positions across all pools. Renders fully on-chain SVG metadata with live P&L.

LpNFT

ERC-721 contract. One token per pool, minted at market creation. The holder has exclusive LP authority over the associated pool.

Data flow

Trader                          LP NFT Holder
  │                                  │
  ├── openLong/openShort ───►  EXNIHILOPool
  │                               │    │
  │                    mint ──► AirTokens   ──► PositionNFT (custody)
  │                               │
  ├── closeLong/closeShort ──►  EXNIHILOPool
  │                               │
  │                    burn ──► AirTokens   ──► PositionNFT (release)
  │                               │
  │                          USDC ──► Trader
  │
  └── swap ──────────────────►  EXNIHILOPool (SWAP-1)