Security Best Practices

Smart contract security is paramount because vulnerabilities can result in permanent loss of funds.

Common Vulnerabilities:

Reentrancy: An attacker calls back into your contract before the first execution finishes. The DAO hack in 2016 exploited this.
Prevention: Use the checks-effects-interactions pattern. Update state BEFORE making external calls.

Integer Overflow/Underflow: Arithmetic errors. Solidity 0.8+ has built-in overflow checks, but be careful with unchecked blocks.

Access Control: Forgetting to restrict sensitive functions. Always use modifiers like onlyOwner.

Front-Running: Miners/validators can see pending transactions and insert their own ahead. Use commit-reveal schemes for sensitive operations.

Best Practices:
• Use OpenZeppelin’s audited contracts as building blocks
• Follow the checks-effects-interactions pattern
• Get professional audits before deploying to mainnet
• Use multi-sig wallets for admin functions
• Implement time locks for critical changes
• Write comprehensive test suites with 100% coverage