> ## Documentation Index
> Fetch the complete documentation index at: https://docs.dokrypt.com/llms.txt
> Use this file to discover all available pages before exploring further.

# dokrypt fork

> Fork a live blockchain network for local testing.

## Usage

```bash theme={null}
dokrypt fork [network] [flags]
```

## Arguments

| Argument  | Required | Description                    |
| --------- | -------- | ------------------------------ |
| `network` | No       | Network name or custom RPC URL |

## Flags

| Flag         | Type     | Default | Description                                  |
| ------------ | -------- | ------- | -------------------------------------------- |
| `--url`      | `string` | —       | Custom RPC URL to fork from                  |
| `--block`    | `uint64` | `0`     | Fork at a specific block number (0 = latest) |
| `--chain`    | `string` | —       | Target chain name (for multi-chain setups)   |
| `--accounts` | `int`    | `10`    | Number of accounts to fund                   |

## Description

Resets the local chain to a fork of a live blockchain network. After forking, your local environment has the complete state of the target network at the specified block — you can interact with all deployed contracts (Uniswap, Aave, etc.) as if you were on mainnet.

### How It Works

1. Resolves the network name to an RPC URL (or uses the custom `--url`)
2. Calls `anvil_reset` (or `hardhat_reset`) with forking parameters
3. Waits up to 120 seconds for the fork to complete
4. Fetches the new chain ID and block number
5. Funds the specified number of accounts with 10,000 ETH each

## Supported Networks

| Network   | Aliases               | Chain ID | RPC URL                                 |
| --------- | --------------------- | -------- | --------------------------------------- |
| Ethereum  | `mainnet`, `ethereum` | 1        | `https://eth.llamarpc.com`              |
| Sepolia   | `sepolia`             | 11155111 | `https://rpc.sepolia.org`               |
| Goerli    | `goerli`              | 5        | `https://rpc.ankr.com/eth_goerli`       |
| Polygon   | `polygon`             | 137      | `https://polygon-rpc.com`               |
| Arbitrum  | `arbitrum`            | 42161    | `https://arb1.arbitrum.io/rpc`          |
| Optimism  | `optimism`            | 10       | `https://mainnet.optimism.io`           |
| Base      | `base`                | 8453     | `https://mainnet.base.org`              |
| BSC       | `bsc`                 | 56       | `https://bsc-dataseed.binance.org`      |
| Avalanche | `avalanche`           | 43114    | `https://api.avax.network/ext/bc/C/rpc` |

## Examples

### Fork Ethereum mainnet (latest block)

```bash theme={null}
dokrypt fork mainnet
```

### Fork at a specific block

```bash theme={null}
dokrypt fork mainnet --block 18500000
```

### Fork Polygon

```bash theme={null}
dokrypt fork polygon
```

### Fork with a custom RPC URL

```bash theme={null}
dokrypt fork --url https://your-alchemy-url.com/v2/API_KEY
```

### Fork with more funded accounts

```bash theme={null}
dokrypt fork mainnet --accounts 20
```

### Fork a specific chain in a multi-chain setup

```bash theme={null}
dokrypt fork arbitrum --chain l2
```

## Use Cases

### Test against real DeFi protocols

```bash theme={null}
dokrypt fork mainnet --block 18500000

# Now you can interact with Uniswap, Aave, Compound, etc.
# at the exact state of block 18,500,000
```

### Reproduce a mainnet bug

```bash theme={null}
# Fork at the block just before the bug
dokrypt fork mainnet --block 17999999

# Impersonate the affected account
dokrypt accounts impersonate 0xAffectedAddress...

# Replay the transaction
```

### Test token integrations

```bash theme={null}
dokrypt fork mainnet

# Fund your test account with real USDC
dokrypt chain set-balance 0xYourAddress... 1000

# Impersonate a whale to get tokens
dokrypt accounts impersonate 0xUSDCWhale...
```