Subnet EVM

Avalanche is a network composed of multiple blockchains. Each blockchain is an instance of a Virtual Machine (VM), much like an object in an object-oriented language is an instance of a class. That is, the VM defines the behavior of the blockchain.

Subnet EVM is the Virtual Machine (VM) that defines the Subnet Contract Chains. Subnet EVM is a simplified version of Coreth VM (C-Chain).

This chain implements the Ethereum Virtual Machine and supports Solidity smart contracts as well as most other Ethereum client functionality.

Building

The Subnet EVM runs in a separate process from the main AvalancheGo process and communicates with it over a local gRPC connection.

AvalancheGo Compatibility

[v0.1.0] AvalancheGo@v1.7.0-v1.7.4
[v0.1.1-v0.1.2] AvalancheGo@v1.7.5-v1.7.6

API

The Subnet EVM supports the following API namespaces:

• eth
• personal
• txpool
• debug

Only the eth namespace is enabled by default. Full documentation for the C-Chain's API can be found here.

Compatibility

The Subnet EVM is compatible with almost all Ethereum tooling, including Remix, Metamask and Truffle.

Differences Between Subnet EVM and Coreth

• Added configurable fees and gas limits in genesis
• Merged Avalanche hardforks into the single "Subnet EVM" hardfork
• Removed Atomic Txs and Shared Memory
• Removed Multicoin Contract and State

Setting a Custom Fee Recipient

By default, all fees are burned (sent to the blackhole address). However, it is possible to enable block producers to set a fee recipient (get compensated for blocks they produce).

To enable this feature, you'll need to add the following to your genesis file (under the "config" key):

{
  "config": {
    "allowFeeRecipients":true
  }
}

Next, you'll need to update your chain config with the following:

{
  "feeRecipient":"<YOU 0x-ADDRESS>"
}

Note: If you enable this feature but a validator doesn't specify a "feeRecipient", the fees will be burned in blocks they produce.

Restricting Smart Contract Deployers

If you'd like to restrict who has the ability to deploy contracts on your subnet, you can provide an AllowList configuration in your genesis file:

{
  "config": {
    "chainId": 99999,
    "homesteadBlock": 0,
    "eip150Block": 0,
    "eip150Hash": "0x2086799aeebeae135c246c65021c82b4e15a2c451340993aacfd2751886514f0",
    "eip155Block": 0,
    "eip158Block": 0,
    "byzantiumBlock": 0,
    "constantinopleBlock": 0,
    "petersburgBlock": 0,
    "istanbulBlock": 0,
    "muirGlacierBlock": 0,
    "subnetEVMTimestamp": 0,
    "feeConfig": {
      "gasLimit": 20000000,
      "minBaseFee": 1000000000,
      "targetGas": 100000000,
      "baseFeeChangeDenominator": 48,
      "minBlockGasCost": 0,
      "maxBlockGasCost": 10000000,
      "targetBlockRate": 2,
      "blockGasCostStep": 500000
    },
    "contractDeployerAllowListConfig": {
      "blockTimestamp": 0,
      "adminAddresses":["0x8db97C7cEcE249c2b98bDC0226Cc4C2A57BF52FC"]
    }
  },
  "alloc": {
    "8db97C7cEcE249c2b98bDC0226Cc4C2A57BF52FC": {
      "balance": "0x52B7D2DCC80CD2E4000000"
    }
  },
  "nonce": "0x0",
  "timestamp": "0x0",
  "extraData": "0x00",
  "gasLimit": "0x1312D00",
  "difficulty": "0x0",
  "mixHash": "0x0000000000000000000000000000000000000000000000000000000000000000",
  "coinbase": "0x0000000000000000000000000000000000000000",
  "number": "0x0",
  "gasUsed": "0x0",
  "parentHash": "0x0000000000000000000000000000000000000000000000000000000000000000"
}

In this example, 0x8db97C7cEcE249c2b98bDC0226Cc4C2A57BF52FC is named as the Admin of the ContractDeployerAllowList. This enables them to add other Admins or to add Deployers. Both Admins and Deployers can deploy contracts. To provide a great UX with factory contracts, the tx.Origin is checked for being a valid deployer instead of the caller of CREATE. This means that factory contracts will still be able to create new contracts as long as the sender of the original transaction is an allow listed deployer.

The Stateful Precompile powering the ContractDeployerAllowList adheres to the following Solidity interface at 0x0200000000000000000000000000000000000000 (you can load this interface and interact directly in Remix):

// (c) 2022-2023, Ava Labs, Inc. All rights reserved.
// See the file LICENSE for licensing terms.

// SPDX-License-Identifier: MIT

pragma solidity >=0.8.0;

interface AllowListInterface {
    // Set [addr] to have the admin role over the allow list
    function setAdmin(address addr) external;

    // Set [addr] to be enabled on the allow list
    function setEnabled(address addr) external;

    // Set [addr] to have no role over the allow list
    function setNone(address addr) external;

    // Read the status of [addr]
    function readAllowList(address addr) external view returns (uint256);
}

If you attempt to add a Deployer and you are not an Admin, you will see something like:

If you attempt to deploy a contract but you are not an Admin not a Deployer, you will see something like:

Run Local Network

scripts/run.sh automatically installs [avalanchego], sets up a local network, and creates a subnet-evm genesis file.

# to startup a local cluster (good for development)
cd ${HOME}/go/src/github.com/ava-labs/subnet-evm
./scripts/run.sh 1.7.5 0x8db97C7cEcE249c2b98bDC0226Cc4C2A57BF52FC

Once the the network is started up, the following info will be printed to the console:

Logs Directory: /var/folders/mp/6jm81gc11dv3xtcwxmrd8mcr0000gn/T/runnerlogs2402729383
PID: 90118

EVM Chain ID: 99999
Funded Address: 0x8db97C7cEcE249c2b98bDC0226Cc4C2A57BF52FC
RPC Endpoints:
- http://localhost:53423/ext/bc/AHdWCyWDaudRX4JkHNgpzyMFdhHK7iEgB4HHMTuarzWghkAdg/rpc
- http://localhost:53425/ext/bc/AHdWCyWDaudRX4JkHNgpzyMFdhHK7iEgB4HHMTuarzWghkAdg/rpc
- http://localhost:53427/ext/bc/AHdWCyWDaudRX4JkHNgpzyMFdhHK7iEgB4HHMTuarzWghkAdg/rpc
- http://localhost:53429/ext/bc/AHdWCyWDaudRX4JkHNgpzyMFdhHK7iEgB4HHMTuarzWghkAdg/rpc
- http://localhost:53431/ext/bc/AHdWCyWDaudRX4JkHNgpzyMFdhHK7iEgB4HHMTuarzWghkAdg/rpc

WS Endpoints:
- ws://localhost:53423/ext/bc/AHdWCyWDaudRX4JkHNgpzyMFdhHK7iEgB4HHMTuarzWghkAdg/ws
- ws://localhost:53425/ext/bc/AHdWCyWDaudRX4JkHNgpzyMFdhHK7iEgB4HHMTuarzWghkAdg/ws
- ws://localhost:53427/ext/bc/AHdWCyWDaudRX4JkHNgpzyMFdhHK7iEgB4HHMTuarzWghkAdg/ws
- ws://localhost:53429/ext/bc/AHdWCyWDaudRX4JkHNgpzyMFdhHK7iEgB4HHMTuarzWghkAdg/ws
- ws://localhost:53431/ext/bc/AHdWCyWDaudRX4JkHNgpzyMFdhHK7iEgB4HHMTuarzWghkAdg/ws

MetaMask Quick Start:
Funded Address: 0x8db97C7cEcE249c2b98bDC0226Cc4C2A57BF52FC
Network Name: Local EVM
RPC URL: http://localhost:53423/ext/bc/AHdWCyWDaudRX4JkHNgpzyMFdhHK7iEgB4HHMTuarzWghkAdg/rpc
Chain ID: 99999
Curreny Symbol: LEVM

You can then ping the local cluster or add the network to MetaMask:

curl --location --request POST 'http://localhost:61278/ext/bc/2Z36RnQuk1hvsnFeGWzfZUfXNr7w1SjzmDQ78YxfTVNAkDq3nZ/rpc' \
--header 'Content-Type: application/json' \
--data-raw '{
    "jsonrpc": "2.0",
    "method": "eth_blockNumber",
    "params":[],
    "id": 1
}'
<<COMMENT
{
    "jsonrpc": "2.0",
    "id": 1,
    "result": "0x0"
}
COMMENT

To terminate the cluster, kill the PID:

kill -2 55547

Fuji Subnet Deployment

Ready to take the subnet-evm for a spin? Follow this tutorial and you can get your own EVM on your own subnet spun up on Fuji in a jiffy!

You can find an example of a genesis file to use when launching your own subnet-evm in the networks folder.

Prerequisites

• 1+ nodes running on Fuji (does not need to be a validator)
• subnet-cli installed
• subnet-cli private key with some Fuji AVAX (see faucet)

Build Binary

First, you'll need to compile the subnet-evm into a binary that AvalancheGo can interact with. To do this, run the following commands (assumes you don't yet have the subnet-evm repository downloaded):

git clone https://github.com/ava-labs/subnet-evm.git;
cd subnet-evm;
./scripts/build.sh build/srEXiWaHuhNyGwPUi444Tu47ZEDwxTWrbQiuD7FmgSAQ6X7Dy;

Move Binary

Once the subnet-evm binary is built, you'll need to move it to AvalancheGo's plugin directory (within the --build-dir) so it can be run by your node. When building from source, this defaults to ~/avalanchego/build/plugins. This build directory is structured as:

build-dir
|_avalanchego
    |_plugins
      |_evm

To put the subnet-evm binary in the right place, run the following command (assuming the avalanchego and subnet-evm repos are in the same folder):

mv ./subnet-evm/build/srEXiWaHuhNyGwPUi444Tu47ZEDwxTWrbQiuD7FmgSAQ6X7Dy ./avalanchego/build/plugins;

Run subnet-cli wizard

The easiest and fastest way to get your new subnet off the ground is to use the subnet-cli. This powerful CLI can add validators, create subnets, and create blockchains.

The subnet-cli DOES NOT need to be run on the same host where you are running your validator. By default, it interfaces exclusively with the public Avalanche API Endpoints.

To make it as easy as possible to get started, the subnet-cli also provides a wizard command that takes care of EVERYTHING for you. TL;DR, type one command and you'll have a subnet with a running subnet-evm instance 5 minutes later.

To make NodeID-XXXX a validator, create a subnet, add NodeID-XXXX to the subnet (comma separated with multiple validators), and create a subnet-evm-based blockhain, run the following command:

subnet-cli wizard \
--node-ids=NodeID-XXXX \
--vm-genesis-path=networks/11111/genesis.json \
--vm-id=srEXiWaHuhNyGwPUi444Tu47ZEDwxTWrbQiuD7FmgSAQ6X7Dy \
--chain-name=subnetevm

The vm-id was generated by calling subnet-cli create VMID subnetevm. You can use any value here, the only important thing is to make sure the binary you generate has the same name.

Add New Subnet to Node Whitelist

During the execution of the wizard command, you will be prompted to add your new subnetID to your node. This is done using the whitelisted-subnets config. You can provide the whitelisted-subnets argument by modifying your config file or providing an argument on startup.

Example Config File:

{
  "network-id":"fuji",
  "health-check-frequency":"2s",
  "log-display-level":"INFO",
  "log-level":"INFO",
  "whitelisted-subnets":"<PROVIDED BY SPACES-CLI>"
}

Example Node Args:

--whitelisted-subnets=<PROVIDED BY SPACES CLI> --network-id=fuji

Restart Node

Once you've updated your config, you'll need to restart your AvalancheGo node for the changes to take effect.

If you completed the steps successfully, you'll see the node print out:

INFO [01-25|16:47:04] chains/manager.go#246: creating chain:
    ID: 2AM3vsuLoJdGBGqX2ibE8RGEq4Lg7g4bot6BT1Z7B9dH5corUD
    VMID:sqja3uK17MJxfC7AN8nGadBw9JK5BcrsNwNynsqP5Gih8M5Bm
INFO [01-25|16:47:04] api/server/server.go#203: adding route /ext/bc/2JVSBoinj9C2J33VntvzYtVJNZdN2NKiwwKjcumHUWEb5DbBrm/events
INFO [01-25|16:47:04] api/server/server.go#203: adding route /ext/bc/2JVSBoinj9C2J33VntvzYtVJNZdN2NKiwwKjcumHUWEb5DbBrm
INFO [01-25|16:47:04] api/server/server.go#203: adding route /ext/bc/2JVSBoinj9C2J33VntvzYtVJNZdN2NKiwwKjcumHUWEb5DbBrm/wallet
INFO [01-25|16:47:04] <2AM3vsuLoJdGBGqX2ibE8RGEq4Lg7g4bot6BT1Z7B9dH5corUD Chain> snow/engine/snowman/transitive.go#67: initializing consensus engine
INFO [01-25|16:47:04] <2AM3vsuLoJdGBGqX2ibE8RGEq4Lg7g4bot6BT1Z7B9dH5corUD Chain> snow/engine/snowman/bootstrap/bootstrapper.go#225: Starting bootstrap...
INFO [01-25|16:47:04] <P Chain> snow/engine/snowman/bootstrap/bootstrapper.go#458: waiting for the remaining chains in this subnet to finish syncing
INFO [01-25|16:47:04] api/server/server.go#203: adding route /ext/bc/2AM3vsuLoJdGBGqX2ibE8RGEq4Lg7g4bot6BT1Z7B9dH5corUD/public
INFO [01-25|16:47:04] <2AM3vsuLoJdGBGqX2ibE8RGEq4Lg7g4bot6BT1Z7B9dH5corUD Chain> snow/engine/common/bootstrapper.go#235: Bootstrapping started syncing with 2 vertices in the accepted frontier
INFO [01-25|16:47:05] <2AM3vsuLoJdGBGqX2ibE8RGEq4Lg7g4bot6BT1Z7B9dH5corUD Chain> snow/engine/snowman/bootstrap/bootstrapper.go#419: bootstrapping fetched 69 blocks. Executing state transitions...
INFO [01-25|16:47:06] <2AM3vsuLoJdGBGqX2ibE8RGEq4Lg7g4bot6BT1Z7B9dH5corUD Chain> snow/engine/common/queue/jobs.go#181: executed 69 operations
INFO [01-25|16:47:06] <2AM3vsuLoJdGBGqX2ibE8RGEq4Lg7g4bot6BT1Z7B9dH5corUD Chain> snow/engine/snowman/transitive.go#354: bootstrapping finished with 2DUxceCx71L5TLTeLpKUQxSBVm8vTKPmFs2usAyRnusUzs4Q4M as the last accepted block

If you didn't put the subnet-evm binary in the right place, you'll see something like:

INFO [01-26|05:54:19] chains/manager.go#246: creating chain:
    ID: 2AM3vsuLoJdGBGqX2ibE8RGEq4Lg7g4bot6BT1Z7B9dH5corUD
    VMID:sqja3uK17MJxfC7AN8nGadBw9JK5BcrsNwNynsqP5Gih8M5Bm
ERROR[01-26|05:54:19] chains/manager.go#270: error creating chain 2AM3vsuLoJdGBGqX2ibE8RGEq4Lg7g4bot6BT1Z7B9dH5corUD: error while looking up VM: there is no ID with alias sqja3uK17MJxfC7AN8nGadBw9JK5BcrsNwNynsqP5Gih8M5Bm

Join the WAGMI Subnet Demo

Thanks to the @0xNeonMonsters for the logo!

The WAGMI ("We're All Going to Make It") Subnet Demo is a high throughput testbed for EVM (Ethereum Virtual Machine) optimizations. It is parameterized to run at a factor more capacity than Fuji/Mainnet C-Chain and will be used to experiment with release candidates before they make it into an official coreth release.

We created a basic WAGMI explorer that surfaces aggregated usage statistics about the subnet. If you'd like to see any other stats added to this site, please send a DM to @_patrickogrady on Twitter.

Everyone that has used the the C-Chain more than twice (~970k addresses) has been airdropped 10 WGM tokens. With the current fee parameterization, this should be enough for hundreds of txs.

This is one of the first cases of using Avalanche Subnets as a proving ground for changes in a production VM (coreth). Many underestimate how useful the isolation of subnets is for performing complex VM testing on a live network (without impacting the stability of the primary network).

Network Creation

To create WAGMI, all we had to do was run the following command:

subnet-cli wizard \
--node-ids=NodeID-9TCq8np31pHjjhGaHtLjs6ptYYPEt3LGb,NodeID-BrYXghQSu6KKGjuzhs3nrkcB46Wc2yYHy,NodeID-89UCR1CsPzzEHuknxhJHKxuFPNCyPz7Bu,NodeID-Hfm8gpD4DpCz4KTzt2osJPfFvu7az3qiD,NodeID-LkdxkfYhg6nSw1EEUxDUSYPXPwmr2cUet \
--vm-genesis-path=networks/11111/genesis.json \
--vm-id=srEXiWaHuhNyGwPUi444Tu47ZEDwxTWrbQiuD7FmgSAQ6X7Dy \
--chain-name=wagmi

This added these NodeIDs as validators on Fuji, created the WAGMI Subnet, added all validators to the WAGMI subnet, and created the WAGMI chain.

• SubnetID: 28nrH5T2BMvNrWecFcV3mfccjs6axM1TVyqe79MCv2Mhs8kxiY
• ChainID: 2ebCneCbwthjQ1rYT41nhd7M76Hc6YmosMAQrTFhBq8qeqh6tt

Network Parameters

Network ID: 11111
Chain ID: 11111
Block Gas Limit: 20,000,000 (2.5x C-Chain)
10s Gas Target: 100,000,000 (~6.67x C-Chain)
Min Fee: 1 GWei (4% of C-Chain)
Target Block Rate: 2s (Same as C-Chain)

Adding to MetaMask

Network Name: WAGMI
RPC URL: https://api.trywagmi.xyz/rpc
Chain ID: 11111
Symbol: WGM

Wrapped WAGMI

Info

Address: 0x3Ee7094DADda15810F191DD6AcF7E4FFa37571e4
IPFS: /ipfs/QmVAuheeidjD2ktdX3sSHMQqSfcjtmca1g9jr7w9GQf7pU

Metadata

{"compiler":{"version":"0.5.17+commit.d19bba13"},"language":"Solidity","output":{"abi":[{"anonymous":false,"inputs":[{"indexed":true,"internalType":"address","name":"src","type":"address"},{"indexed":true,"internalType":"address","name":"guy","type":"address"},{"indexed":false,"internalType":"uint256","name":"wad","type":"uint256"}],"name":"Approval","type":"event"},{"anonymous":false,"inputs":[{"indexed":true,"internalType":"address","name":"dst","type":"address"},{"indexed":false,"internalType":"uint256","name":"wad","type":"uint256"}],"name":"Deposit","type":"event"},{"anonymous":false,"inputs":[{"indexed":true,"internalType":"address","name":"src","type":"address"},{"indexed":true,"internalType":"address","name":"dst","type":"address"},{"indexed":false,"internalType":"uint256","name":"wad","type":"uint256"}],"name":"Transfer","type":"event"},{"anonymous":false,"inputs":[{"indexed":true,"internalType":"address","name":"src","type":"address"},{"indexed":false,"internalType":"uint256","name":"wad","type":"uint256"}],"name":"Withdrawal","type":"event"},{"payable":true,"stateMutability":"payable","type":"fallback"},{"constant":true,"inputs":[{"internalType":"address","name":"","type":"address"},{"internalType":"address","name":"","type":"address"}],"name":"allowance","outputs":[{"internalType":"uint256","name":"","type":"uint256"}],"payable":false,"stateMutability":"view","type":"function"},{"constant":false,"inputs":[{"internalType":"address","name":"guy","type":"address"},{"internalType":"uint256","name":"wad","type":"uint256"}],"name":"approve","outputs":[{"internalType":"bool","name":"","type":"bool"}],"payable":false,"stateMutability":"nonpayable","type":"function"},{"constant":true,"inputs":[{"internalType":"address","name":"","type":"address"}],"name":"balanceOf","outputs":[{"internalType":"uint256","name":"","type":"uint256"}],"payable":false,"stateMutability":"view","type":"function"},{"constant":true,"inputs":[],"name":"decimals","outputs":[{"internalType":"uint8","name":"","type":"uint8"}],"payable":false,"stateMutability":"view","type":"function"},{"constant":false,"inputs":[],"name":"deposit","outputs":[],"payable":true,"stateMutability":"payable","type":"function"},{"constant":true,"inputs":[],"name":"name","outputs":[{"internalType":"string","name":"","type":"string"}],"payable":false,"stateMutability":"view","type":"function"},{"constant":true,"inputs":[],"name":"symbol","outputs":[{"internalType":"string","name":"","type":"string"}],"payable":false,"stateMutability":"view","type":"function"},{"constant":true,"inputs":[],"name":"totalSupply","outputs":[{"internalType":"uint256","name":"","type":"uint256"}],"payable":false,"stateMutability":"view","type":"function"},{"constant":false,"inputs":[{"internalType":"address","name":"dst","type":"address"},{"internalType":"uint256","name":"wad","type":"uint256"}],"name":"transfer","outputs":[{"internalType":"bool","name":"","type":"bool"}],"payable":false,"stateMutability":"nonpayable","type":"function"},{"constant":false,"inputs":[{"internalType":"address","name":"src","type":"address"},{"internalType":"address","name":"dst","type":"address"},{"internalType":"uint256","name":"wad","type":"uint256"}],"name":"transferFrom","outputs":[{"internalType":"bool","name":"","type":"bool"}],"payable":false,"stateMutability":"nonpayable","type":"function"},{"constant":false,"inputs":[{"internalType":"uint256","name":"wad","type":"uint256"}],"name":"withdraw","outputs":[],"payable":false,"stateMutability":"nonpayable","type":"function"}],"devdoc":{"methods":{}},"userdoc":{"methods":{}}},"settings":{"compilationTarget":{"contracts/wwagmi.sol":"WWAGMI"},"evmVersion":"istanbul","libraries":{},"optimizer":{"enabled":false,"runs":200},"remappings":[]},"sources":{"contracts/wwagmi.sol":{"keccak256":"0x0a6ce5559225d3c99db4a5e24777049df3c84886ba9a08147f23afae4261b509","urls":["bzz-raw://0aef254c65ae30b578256a7e2496ed18bf0cb68e97f5831050e17a2cf0192a7e","dweb:/ipfs/QmSwAbdnaYvrjDHTKnE3qBZ3smT7uipSSfSGBUiKWmNWEY"]}},"version":1}

Code

// Copyright (C) 2015, 2016, 2017 Dapphub

// This program is free software: you can redistribute it and/or modify
// it under the terms of the GNU General Public License as published by
// the Free Software Foundation, either version 3 of the License, or
// (at your option) any later version.

// This program is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
// GNU General Public License for more details.

// You should have received a copy of the GNU General Public License
// along with this program.  If not, see <http://www.gnu.org/licenses/>.

// Contract name, token name, and token symbol modified by Ava Labs 2020

pragma solidity >=0.4.22 <0.6;

contract WWAGMI{
    string public name     = "Wrapped WAGMI";
    string public symbol   = "WWAGMI";
    uint8  public decimals = 18;

    event  Approval(address indexed src, address indexed guy, uint wad);
    event  Transfer(address indexed src, address indexed dst, uint wad);
    event  Deposit(address indexed dst, uint wad);
    event  Withdrawal(address indexed src, uint wad);

    mapping (address => uint)                       public  balanceOf;
    mapping (address => mapping (address => uint))  public  allowance;

    function() external payable {
        deposit();
    }
    function deposit() public payable {
        balanceOf[msg.sender] += msg.value;
        emit Deposit(msg.sender, msg.value);
    }
    function withdraw(uint wad) public {
        require(balanceOf[msg.sender] >= wad);
        balanceOf[msg.sender] -= wad;
        msg.sender.transfer(wad);
        emit Withdrawal(msg.sender, wad);
    }

    function totalSupply() public view returns (uint) {
        return address(this).balance;
    }

    function approve(address guy, uint wad) public returns (bool) {
        allowance[msg.sender][guy] = wad;
        emit Approval(msg.sender, guy, wad);
        return true;
    }

    function transfer(address dst, uint wad) public returns (bool) {
        return transferFrom(msg.sender, dst, wad);
    }

    function transferFrom(address src, address dst, uint wad)
        public
        returns (bool)
    {
        require(balanceOf[src] >= wad);

        if (src != msg.sender && allowance[src][msg.sender] != uint(-1)) {
            require(allowance[src][msg.sender] >= wad);
            allowance[src][msg.sender] -= wad;
        }

        balanceOf[src] -= wad;
        balanceOf[dst] += wad;

        emit Transfer(src, dst, wad);

        return true;
    }
}