The blog delves into the fundamental design principles of creating upgradable smart contracts, specifically focusing on Ethereum and EVM-based contracts. It explains the need for upgrading smart contracts to fix bugs, improve functionality, optimize code for gas efficiency, and adapt to technological or societal changes. Despite the immutability of blockchain data, the blog illustrates how smart contracts can be upgraded through architectural patterns like the Proxy Pattern, which involves substituting an old contract with a new one while maintaining user interaction consistency through a stable proxy address. It covers two primary proxy patterns: the Transparent Proxy Pattern, which routes user calls to the logic contract unless initiated by an admin, and the Universal Upgradable Proxy Standard (UUPS), which allows for upgradeability management via the logic contract itself. The blog provides practical insights and a step-by-step guide using OpenZeppelin tools, Hardhat, and Solidity to deploy and upgrade smart contracts, emphasizing the importance of managing storage variables and addressing potential issues like storage collisions and function selector clashes.