Architecture Overview

graph TB
    subgraph "User Layer"
        A[Wallets] --> B[dApps]
        B --> C[SDKs/Libraries]
    end
    
    subgraph "RPC Layer"
        D[Public RPC]
        E[WebSocket]
    end
    
    subgraph "Execution Layer"
        F[Sequencer]
        G[EVM]
        H[State Manager]
    end
    
    subgraph "Storage Layer"
        I[State DB]
        J[Block DB]
    end
    
    subgraph "Network Layer"
        K[P2P Network]
        L[Block Propagation]
    end
    
    C --> D
    C --> E
    D --> F
    E --> F
    F --> G
    G --> H
    H --> I
    H --> J
    F --> K
    K --> L

{
  "number": 1234567,
  "hash": "0x...",
  "parentHash": "0x...",
  "stateRoot": "0x...",
  "transactionsRoot": "0x...",
  "receiptsRoot": "0x...",
  "timestamp": 1699564800,
  "gasLimit": 30000000,
  "gasUsed": 15234567,
  "baseFeePerGas": 1000000000,
  "miner": "0x...",
  "transactions": [...]
}

State Root
├── Account 0x1111...
│   ├── Balance: 100 PAX
│   ├── Nonce: 5
│   ├── Code Hash: 0x...
│   └── Storage Root
│       ├── Slot 0: value1
│       └── Slot 1: value2
├── Account 0x2222...
│   ├── Balance: 50 PAX
│   └── Nonce: 2
└── ...

contract Example {
    uint256 public slot0;           // Storage slot 0
    mapping(address => uint256) public balances; // Slot 1 base
    
    // balances[addr] stored at keccak256(addr, 1)
}

graph LR
    A[Sequencer] -->|New Block| B[Node 1]
    A -->|New Block| C[Node 2]
    B -->|Relay| D[Node 3]
    C -->|Relay| E[Node 4]
    D -->|Relay| F[Node 5]

datadir/
├── chaindata/         # Blockchain and state data
│   ├── ancient/      # Old blocks (compressed)
│   └── current/      # Recent blocks
├── lightchaindata/   # Light client data
├── nodes/            # P2P network data
└── keystore/         # Account keys (if any)

interface ISequencerFeeVault {
    function withdraw() external;
}

// Access fee vault
ISequencerFeeVault vault = ISequencerFeeVault(
    0x4200000000000000000000000000000000000011
);