The rapid development of decentralized applications requires special attention to security: any vulnerabilities can lead to significant financial losses and undermine user trust. In this talk, I will discuss the security audit of smart contracts on the TON network, highlighting the main differences from traditional blockchains. I will share my experience identifying vulnerabilities and discuss potential issues when developing on FunC and Tact. The talk will also include an overview of best practices for auditing smart contracts on TON.