UPGRADEABLE STORAGE

A comprehensive demonstration of Solidity patterns including storage management, inheritance, UUPS upgrades, delegate calls, and proxy implementations. Built with Foundry.

Core Contracts

1. Storage Contracts

SimpleStorage

• Stores numbers and person structs (name + favorite number)
• Features:
  • store() and addPerson() function for storing name and favoriteNumber
  • Multiple getter patterns
  • Euclidean algorithm utility

AddFiveStorage (inherits SimpleStorage)

• Overrides store() to add 5 to all inputs
• Maintains all parent functionality

2. Upgradeable Implementations

UUPSUSimpleStorage (inherits simpleStorage)

• UUPS upgradeable version
• Initializes with value 3 to be stored in myFavoriteNumber
• Ownable upgrade authorization

UUPSUAddFiveStorage (inherits AddFiveStorage)

• UUPS upgradeable +5 version
• Reinitializable (version 2) with value 5 (+5 effect)

3. Proxy & Delegate Call Systems

DelegateUpgradeable

Demonstrates:

• Target contract with multiple storage variables
• Proxy contract using delegatecall to:
  • Modify storage in context of proxy
  • Preserve msg.sender and msg.value
• Dynamic function calling with:
  • abi.encodeWithSignature
  • Raw function selector calculation

Key Features:

• Shows storage slot preservation
• Error handling for failed calls
• Payable function delegation

SmallProxy

Minimal Upgradeable Proxy:

• Implements EIP-1967 storage slot
• Assembly-level implementation:
  • sstore/sload for implementation address
  • Storage slot inspection methods
• Features:
  • setImplementation() for upgrades
  • Storage inspection functions
  • Data encoding helper

Key Patterns Demonstrated

1. Delegate Call Pattern

   • Execute logic in target contract's context
   • Preserves proxy's storage layout
   • Shows msg.sender/value preservation

2. Proxy Upgrade Pattern

   • EIP-1967 implementation slot
   • Storage slot collision prevention
   • Minimal proxy implementation

3. UUPS Upgrade Pattern

   • Gas-efficient upgrades
   • Upgrade authorization via ownership
   • Versioned initialization

Quick Start

git clone https://github.com/manaxtech/foundry-upgradeable-simple-storage.git

make all  # Installs dependencies, compiles