• My Example

User ⇒ Proxy ===delegatecall ==⇒ V1_logic

Proxyはアップグレードしないためユーザーはコントラクトがアップグレードしても常に同一のアドレスに対してトランザクションを送信することが可能になります。

Our recommendation is now shifting towards UUPS proxies

• lightweight
• versatile(generative)

While both of these share the same interface for upgrades,

• Transparent Proxy
  • include the upgrade and admin logic in the proxy itself.
  • This means TransparentUpgradeableProxy is more expensive to deploy
• UUPS Proxy
  • handled by the implementation
  • can eventually be removed
  • UUPS proxies do not contain an upgrade mechanism on the proxy
  • “Upgrade mechanism of Proxy” has to be included in the implementation.
    • We can add this mechanism by inheriting UUPSUpgradeable.
    • And this will also require that we implement an authorization function to define who should be allowed to upgrade the contract.
      • logic側でupgradeする際の実行者は制限する必要性があるからownableだね
      • Example Code

DelegateCall

UUPS proxies are implemented using an [ERC1967Proxy](<https://docs.openzeppelin.com/contracts/4.x/api/proxy#ERC1967Proxy>) Note that this proxy is not by itself upgradeable.