Tutorial: Building a DeFi App with sBTC

Overview

This tutorial will guide you through the process of creating a simple decentralized lending application that uses sBTC as collateral. We will cover the essential steps, from setting up your development environment to writing the smart contract and interacting with it.

Prerequisites

• A local Synergeia testnet running. (See the Interactive Testnet Guide)
• Basic knowledge of Rust and smart contract development.

The Smart Contract

Below is a simplified version of the smart contract for our lending application. This contract will allow users to deposit sBTC as collateral and borrow a hypothetical stablecoin.

// Note: This is a conceptual example and not production-ready code.

// A simplified representation of our lending contract
struct LendingContract {
    collateral: HashMap, // User's sBTC balance
    debt: HashMap,       // User's borrowed stablecoin balance
}

impl LendingContract {
    // Deposit sBTC as collateral
    pub fn deposit_collateral(&mut self, user: User, amount: u64) {
        *self.collateral.entry(user).or_insert(0) += amount;
    }

    // Borrow stablecoins against collateral
    pub fn borrow(&mut self, user: User, amount: u64) {
        // In a real application, you would check the user's collateralization ratio here.
        *self.debt.entry(user).or_insert(0) += amount;
    }
}