# Etherlink

Source: https://developers.bitgo.com/docs/etherlink

## Overview

Etherlink is an EVM-compatible, non-custodial Layer 2 blockchain powered by Tezos Smart Rollup technology. It offers sub-500 ms confirmation times through a sequencer, nearly free transaction costs, and inherits security from the Tezos Layer 1 through a permissionless fraud-proof system. Etherlink supports all standard Ethereum tooling and enables asset transfers across EVM chains. XTZ covers gas fees.

## Explorer
<a href="https://explorer.etherlink.com/" target="_blank" rel="noreferrer">https://explorer.etherlink.com/</a>


## Wallets Types

BitGo enables holding xtzevm in the following wallet types:

|                  | Multisig Cold | Multisig Hot | MPC Cold | MPC Hot |
| ---------------- | ------------- | ------------ | -------- | ------- |
| **Custody**      | ❌            | ❌           | ✅       | ❌      |
| **Self-Custody** | ❌            | ❌           | ✅       | ✅      |

## Ticker Symbols

| Mainnet | Testnet |
| ------- | ------- |
| XTZEVM  | TXTZEVM |

## Faucet

You can use a faucet to obtain free testnet txtzevm for development and testing purposes.

**Faucet:** https://shadownet.faucet.etherlink.com/

## Units

Each Etherlink XTZ contains `1,000,000,000,000,000,000` (<code>10<sup>18</sup></code>) wei, so not even a single XTZ can be stored numerically without exceeding the range of JavaScript numbers. Gas fees use gwei as the denomination.

- 1 XTZ = <code>10<sup>18</sup></code> wei
- 1 wei = <code>10<sup>-18</sup></code> XTZ
- 1 gwei = <code>10<sup>-9</sup></code> XTZ

For that reason, only string balance properties are available, which are `balanceString`, `confirmedBalanceString`, and
`spendableBalanceString`.

## Tokens

Etherlink supports the ERC20 token standard. ERC20 tokens on Etherlink are available as BitGo supported assets.

## Fees

Etherlink supports EIP-1559 transaction pricing. Each transaction includes a base fee that fluctuates based on network demand and the protocol burns it algorithmically, plus an optional priority fee to incentivize block producers. Transaction costs on Etherlink are minimal, with an ERC-20 transaction costing $0.001 or less. As a Layer 2, Etherlink avoids the per-transaction gas fees of Layer 1 and incurs only minimal costs when publishing state to the Tezos Layer 1.

## Create Wallet

```javascript
bitgo
  .coin('txtzevm')
  .wallets()
  .generateWallet({
    label: 'My Test Wallet',
    passphrase: 'secretpassphrase1a5df8380e0e30',
    enterprise: '5612c2beeecf83610b621b90964448cd',
    walletVersion: 4,
  })
  .then(function (wallet) {
    // print the new wallet
    console.dir(wallet);
  });
```
```shell
export BITGO_EXPRESS_HOST="<YOUR_LOCALHOST>"
export COIN="txtzevm"
export ACCESS_TOKEN="<YOUR_ACCESS_TOKEN>"
export LABEL="<DESIRED_WALLET_NAME>"
export PASSPHRASE="<YOUR_BITGO_LOGIN_PASSPHRASE>"
export ENTERPRISE_ID="<YOUR_ENTERPRISE_ID>"

curl -X POST \
 http://$BITGO_EXPRESS_HOST/api/v2/$COIN/wallet/generate \
 -H 'Content-Type: application/json' \
 -H "Authorization: Bearer $ACCESS_TOKEN" \
  -d '{
    "label": "'"$LABEL"'",
    "passphrase": "'"$PASSPHRASE"'",
    "enterprise": "'"$ENTERPRISE_ID"'",
    "walletVersion": 4
}'
```

## Create Address

```javascript
bitgo
  .coin('txtzevm')
  .wallets()
  .getWallet({ id: '585c51a5df8380e0e3082e46' })
  .then(function (wallet) {
    return wallet.createAddress();
  })
  .then(function (newAddress) {
    // print new address details
    console.dir(newAddress);
  });
```
```shell
export WALLET="585c51a5df8380e0e3082e46"
export ACCESS_TOKEN="<YOUR_ACCESS_TOKEN>"

curl -X POST \
-H "Authorization: Bearer $ACCESS_TOKEN" \
https://app.bitgo-test.com/api/v2/txtzevm/wallet/$WALLET/address
```

## Consolidate Balance

Etherlink supports Multisignature smart-contract wallets which utilize forwarder smart contracts to enable multiple receive addresses. The forwarder smart contract automatically consolidates native tokens received in your receive addresses to your base address. However, if you receive non-native tokens, such as ERC20 tokens, BitGo initiates a different consolidation transaction to the base address. Additionally, forwarders can only send assets to the base address of the wallet.

## Estimate Fee

```javascript
const BitGoJS = require('../../../src/index.js');
const bitgo = new BitGoJS.BitGo({ env: 'test' });
const accessToken = '<YOUR_ACCESS_TOKEN>';
const coin = 'txtzevm';

async function getFeeEstimate() {
  try {
    await bitgo.authenticateWithAccessToken({ accessToken });
    const res = await bitgo.coin(coin).feeEstimate({ numBlocks: 2 });
    console.dir(res);
  } catch (err) {
    console.error('Error fetching fee estimate:', err);
  }
}

getFeeEstimate();
```
```shell
export COIN="txtzevm"
export ACCESS_TOKEN="<YOUR_ACCESS_TOKEN>"

curl -X GET \
 https://app.bitgo-test.com/api/v2/$COIN/tx/fee \
 -H 'Content-Type: application/json' \
 -H "Authorization: Bearer $ACCESS_TOKEN"
```

## Transact

```javascript
const tx = await fundedWallet.send({
    address: '<DESTINATION_ADDRESS>',
    amount: '<AMOUNT>',
    walletPassphrase: process.env.PASSWORD,
  });
```
```shell
export BITGO_EXPRESS_HOST="<YOUR_LOCALHOST>"
export COIN="txtzevm"
export WALLET_ID="<YOUR_WALLET_ID>"
export ACCESS_TOKEN="<YOUR_ACCESS_TOKEN>"
export ADDRESS="<DESTINATION_ADDRESS>"
export AMOUNT="<AMOUNT_IN_BASE_UNITS>"
export WALLET_PASSPHRASE="<YOUR_WALLET_PASSPHRASE>"

curl -X POST \
 http://$BITGO_EXPRESS_HOST/api/v2/$COIN/wallet/$WALLET_ID/sendcoins \
  -H 'Content-Type: application/json' \
  -H "Authorization: Bearer $ACCESS_TOKEN" \
  -d '{
    "address": "'"$ADDRESS"'",
    "amount": "'"$AMOUNT"'",
    "walletPassphrase": "'"$WALLET_PASSPHRASE"'"
}'
```

## Stake

Etherlink isn't a stakeable asset.