Cairo Upgrades Contents - Starknet Upgrade Model - Using the OpenZeppelin Upgradeable Component - Access Control - Upgrade Safety Starknet Upgrade Model Starknet separates contract instances from contract classes . A class is the compiled program (identified by its class hash); a contract is a deployed instance pointing to a class. Multiple contracts can share the same class. Upgrading a contract means replacing its class hash so it points to a new class. The contract keeps its address, storage, and nonce — only the code changes. This is fundamentally different from EVM proxy patterns: | | St…