Smart Contract Security: Best Practices for Building on Tetreum

Smart contracts are immutable once deployed. A single vulnerability can drain millions of dollars in seconds, with no recourse. Building on Tetreum means inheriting a secure EVM environment — but your contract's security is entirely your responsibility.

The Most Common Smart Contract Vulnerabilities

1. Reentrancy Attacks

The most infamous smart contract vulnerability. An attacker calls your contract's withdrawal function, which sends ETH before updating the balance. During the ETH transfer, the attacker's fallback function calls withdrawal again — recursively draining funds. This attack famously drained $60M from The DAO in 2016.

// VULNERABLE — update state AFTER external call
function withdraw() external {
    uint amount = balances[msg.sender];
    (bool success,) = msg.sender.call{value: amount}("");
    require(success);
    balances[msg.sender] = 0; // Too late!
}

// SAFE — Checks-Effects-Interactions pattern
function withdraw() external {
    uint amount = balances[msg.sender];
    balances[msg.sender] = 0;     // Update first
    (bool success,) = msg.sender.call{value: amount}("");
    require(success);
}

2. Integer Overflow / Underflow

Solidity 0.8.0+ includes built-in overflow protection that reverts automatically. Always use Solidity 0.8.0 or higher for new contracts on Tetreum.

3. Access Control Failures

Functions that modify critical state must be protected with role-based access control. Use OpenZeppelin's Ownable or AccessControl contracts rather than rolling your own.

The Audit Checklist

• Use Slither or Mythril for automated static analysis before any audit
• Test all edge cases including zero amounts, maximum values, and empty arrays
• Write fuzz tests — especially for mathematical logic
• Have at least one external security audit before mainnet deployment
• Implement a bug bounty program post-launch
• Document all trust assumptions clearly in code comments

"The best security audit in the world cannot save a contract with a fundamental architectural flaw. Security must be built in from the first line of code." — Tetreum Security Team