Cross-Chain DEX Smart Contract

A decentralized exchange (DEX) smart contract implementation for Stacks blockchain that enables automated market making, liquidity provision, and token swaps. This contract implements standard AMM (Automated Market Maker) functionality with additional cross-chain capabilities.

Features

• Automated Market Maker (AMM) functionality
• Liquidity pool creation and management
• Token swapping with configurable slippage protection
• Liquidity provider (LP) token minting and management
• Emergency shutdown capability
• Protocol fee mechanism (0.3% total fee, split between protocol and LP)
• NFT trait implementation for LP tokens

Technical Specifications

Fee Structure

• Total Fee: 0.3% (30 basis points)
  • Protocol Fee: 0.03% (3 basis points)
  • LP Fee: 0.27% (27 basis points)

Core Functions

Pool Management

• create-pool: Create a new liquidity pool for a token pair
• add-liquidity: Add liquidity to an existing pool
• get-pool-details: Retrieve pool information
• get-provider-shares: Get LP token information for a provider

Trading

• swap-exact-tokens: Execute a token swap with slippage protection
• calculate-swap-output: Calculate expected output for a swap

Administration

• set-contract-owner: Transfer contract ownership
• toggle-emergency-shutdown: Enable/disable emergency shutdown

Error Codes

Code	Description
u100	Not authorized
u101	Invalid amount
u102	Insufficient balance
u103	Pool not found
u104	Slippage too high
u105	Invalid token pair
u106	Zero liquidity

Usage Examples

Creating a New Pool

(contract-call? .dex create-pool token-x token-y initial-x-amount initial-y-amount)

Adding Liquidity

(contract-call? .dex add-liquidity
    pool-id
    token-x
    token-y
    amount-x
    amount-y
    min-shares)

Executing a Swap

(contract-call? .dex swap-exact-tokens
    pool-id
    token-in
    token-out
    amount-in
    min-amount-out
    is-x-to-y)

Security Considerations

1. The contract implements slippage protection to prevent front-running
2. Emergency shutdown mechanism for crisis management
3. Access control for administrative functions
4. Minimum liquidity requirements to prevent manipulation
5. Contract owner permissions are limited to essential functions

Dependencies

• SIP-010 Fungible Token Trait
• NFT Trait Implementation

Development and Testing

To deploy and test this contract:

1. Ensure you have the Clarity CLI installed
2. Deploy required trait contracts first
3. Deploy this contract
4. Run test suite

License

This smart contract is open source and available under the MIT license.

Contributing

Contributions are welcome! Please submit pull requests with:

• Detailed description of changes
• Updated tests
• Documentation updates