# Introduction

## What is SmolRefuel?

SmolRefuel is the single best solution for gas refueling that allows you to refill your wallet anonymously and gas-free.

The true power of SmolRefuel lies in its multi-chain and multi-asset versatility. You can bridge gas to your destination from over 80 chains and on supported chains, swap tokens to gas completely gas-free. 

While some services limit you to swapping only a few assets, SmolRefuel lets you swap with **ANY** coin. Our four different swap systems allow for you to use any token to receive ETH or other gas tokens like BNB, FTM, MNT, and more.

## Why use SmolRefuel?

Have you ever run out of ETH in the middle of a degen trading spree? Did you score a nice airdrop but don't have any gas to transfer or swap your new coins? Maybe you’re being paid in stablecoins but want to keep your wallet anon without funding from any external wallets? 

Not having gas for transactions and getting your funds stuck sucks, SmolRefuel is your solution.

## Chains supported

We currently support gas-free swaps to refuel on:

* Ethereum
* Optimism
* Arbitrum
* Base
* Polygon
* Polygon zkEVM
* BSC
* Avax
* Fantom
* Mantle
* Mode
* Linea
* Scroll

You can also bridge gas to your destination network from over 80 other chains. For a full list of supported chains visit: [Chains Supported](/chains-supported)


# How to?

For this short tutorial we will walk through one of our loan swaps, as those are the most involved

## First visit [smolrefuel.com](https://smolrefuel.com/)

After arriving, connect your wallet in the top right corner

<figure><img src="https://1957861530-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FDMRccWH2bPhpSeu7BBuh%2Fuploads%2Fsk3a8tkCLrKb90RYEQGJ%2FScreenshot%202024-05-18%20at%2010.08.26%E2%80%AFPM.png?alt=media&amp;token=40aab892-1016-427c-b729-59321408dec3" alt=""><figcaption></figcaption></figure>

## Click on 'Select Chain(s)'

After clicking the dropdown, choose the chain you need gas on

<figure><img src="https://1957861530-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FDMRccWH2bPhpSeu7BBuh%2Fuploads%2Fb3xtXoWj9nVL7vpuhWNw%2FScreenshot%202024-05-18%20at%2010.52.27%E2%80%AFPM.png?alt=media&amp;token=15566a27-e3b2-409b-b36b-6883af670dd5" alt="" width="563"><figcaption></figcaption></figure>

## Click on 'Select Token'

Here you can pick a coin you want to refuel from, if you don't see the coin you want to swap just enter the contract address in the search field

<figure><img src="https://1957861530-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FDMRccWH2bPhpSeu7BBuh%2Fuploads%2FaOF0P9vidbllVMd0fRae%2FScreenshot%202024-05-18%20at%2011.16.14%E2%80%AFPM.png?alt=media&amp;token=4d42446d-fbc4-40af-9e4f-f580040f5538" alt=""><figcaption></figcaption></figure>

## Enter the amount you want to swap

Once you enter how much you want to swap, click on start swap

<figure><img src="https://1957861530-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FDMRccWH2bPhpSeu7BBuh%2Fuploads%2FY3QqCJk0o6fxfGfAb5wT%2FScreenshot%202024-05-18%20at%2011.23.37%E2%80%AFPM.png?alt=media&amp;token=adf62d5b-4ad7-4950-bcdb-cdedf8752c28" alt=""><figcaption></figcaption></figure>

## Sign the loan commitment&#x20;

Click on **Sign Commitment** and sign the transaction in your wallet

<figure><img src="https://1957861530-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FDMRccWH2bPhpSeu7BBuh%2Fuploads%2FZ3lFVl6CtbquTCbCRYsA%2FScreenshot%202024-05-18%20at%2011.24.47%E2%80%AFPM.png?alt=media&amp;token=e70d8ef6-5da5-475a-97db-ba9eb7888019" alt=""><figcaption></figcaption></figure>

## Click on **Approve** and confirm the approval transaction in your wallet

*You may need to be patient here, sometimes there can be just slight delays in you receiving our gas loan since that txn has to be processed and confirmed as well. If you're having issues submitting the approval txn, just try again after waiting 1-5 minutes.*

<figure><img src="https://1957861530-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FDMRccWH2bPhpSeu7BBuh%2Fuploads%2F5wP3F3TXKnMYFO2bz1wE%2FScreenshot%202024-05-18%20at%2011.37.18%E2%80%AFPM.png?alt=media&amp;token=15f9590c-0250-40f1-b138-4570677f03b3" alt=""><figcaption></figcaption></figure>

## Your swap is complete

After your approval transaction is confirmed, SmolRefuel will complete your swap and send you your ETH as well as automatically repay the loan!

<figure><img src="https://1957861530-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FDMRccWH2bPhpSeu7BBuh%2Fuploads%2FykHtEVCNnkUsmWc5FJ5k%2FScreenshot%202024-05-18%20at%2011.26.57%E2%80%AFPM.png?alt=media&amp;token=dc0f3446-51e2-4131-9dc2-eaa0555f7077" alt=""><figcaption></figcaption></figure>

If you're running into issues, you can join our discord and submit a ticket at <https://discord.smolrefuel.com> or DM us on twitter @smolrefuel


# Swaps

Each token has it's own implementation and each chain is different, so in order to cover ALL tokens on the chains we support, we built 4 different mechanisms so tokens that can't be swapped using one mechanism can be covered by another mechanism, thus allowing us to provide swaps for ALL tokens.

## Different types of swaps

In order for SmolRefuel to handle swapping **all** tokens across different networks, we have 4 different types of swaps.

* Permit Swaps - Tokens that support the permit function allow us to transfer and swap your coins to gas, all you need to do is a sign a single message, gas-free.
* Uncollateralized Loan Swaps - For tokens that do not support permit, we loan the user just enough gas to approve trade of the coin they are swapping without taking collateral. In order to get the loan you must sign a transaction agreeing to go through with the swap completely. After using our loan to approve your token, the swap will be completed, the loan will be repaid and you will receive your gas.
* Delegated Swaps - When you have enough gas to approve a token for trade but not enough for a swap, we can trigger the swap transaction for you
* Bundle/MEV Swaps- After switching over to our own RPC, the RPC pretends that your wallet has gas and allows you to submit an approval transaction for your token. After sending this transaction to our RPC, we submit a bundle to Flashbots with the following transactions:&#x20;
  1. We send you gas so you can approve your token
  2. The approval transaction you submitted is confirmed
  3. Your coins are swapped and the gas is sent to you

## Other transactions

For chains where we do not yet support gas-less swaps, we have integrated 3rd party bridge providers so users can send gas across 81 different chains in order to refuel.&#x20;


# Integrate

## How to integrate?

WE heavily recommend integrating with either an iframe or link your users to <https://smolrefuel.com/?partner=YOUR_ADDRESS>, replacing YOUR\_ADDRESS with an address where you want to receive rewards.

## Why integrate SmolRefuel?

* 50% revenue share with you
* Improves UX for your users who need gas to use your dapp

## Revenue share

50% of all revenue generated by your users will be given to you. Payouts will be sent after the amount to send reaches $1000.&#x20;

## Customization

You can add the following values to the query string:

* \`?disableBridges=true\`, this disables bridges making it so users can only swap tokens for gas
* \`?outboundChain=56\`, pre-fills the chain where the user wants to get gas, value should be the chain id
* '?widget=basic', this hides unnecessary info like our logo and docs link so you can create a smol widget

For example, if you want to pre-fill chain to be Optimism, URL should be <https://smolrefuel.com/?outboundChain=10>


# API Integration

### Tokens that support permit

1. Get a quote from odos
2. POST <https://api.smolrefuel.com/quote> with body {"chainId":1,"priceRoute":{... quote from odos ...}, "srcDecimals":18,"params":{"token":"0xC18360217D8F7Ab5e7c516566761Ea12Ce7F9D72","from":"USER\_ADDRESS","amount":"1000000000000000000"}}
3. POST <https://api.smolrefuel.com/refuel> with body {"chainId":1,"priceRoute":{... quote from odos ...}, "srcDecimals":18,"params":{"token":"0xC18360217D8F7Ab5e7c516566761Ea12Ce7F9D72","from":"USER\_ADDRESS","amount":"1000000000000000000", deadline:string, v:number, r:string, s:string}, partner: "your name", tokenPrices:{...}}
4. Trade will be sent and you'll get back a tx hash

### Tokens that don't support permit

1. POST <https://api.smolrefuel.com/loan-quote> with body {"chainId":1,"token":"0x4Ddc2D193948926D02f9B1fE9e1daa0718270ED5","from":"USER\_ADDRESS","amount":"100000000"}
2. Have user sign the message

   ```typescript
   I commit to completing the swap on smolrefuel.com after receiving my loan
   ```
3. Send that signature to POST <https://api.smolrefuel.com/get-loan>, with body

   ```typescript
   {
           chainId,
           token,
           from,
           amount,
           signature,
           partner
    }
   ```
4. Have user send an approve() transaction on the token approving our contract
5. POST <https://api.smolrefuel.com/execute-swap> with body

   ```typescript
   {
           chainId,
           token,
           from,
           partner
   }
   ```


# Chains Supported

We currently support gas-free swaps to refuel on:

* Ethereum
* Optimism
* Arbitrum
* Base
* Polygon
* Polygon zkEVM
* BSC
* Avax
* Fantom
* Mantle
* Mode
* Linea
* Scroll

For all other chains, you are only able to bridge gas coins to your destination network. (ex. ETH on Arbitrum Nova to Blast)&#x20;

## Chains supported for gas bridging

### Inbound Chains:

* Ethereum
* Arbitrum
* Optimism
* Avalanche
* Base
* BSC
* Polygon
* Scroll&#x20;
* Linea
* Blast
* Zora
* Mode
* zkSync

### Outbound Chains:

* Ancient8&#x20;
* Arbitrum Nova
* Arbitrum One
* Astar&#x20;
* Astar zkEVM
* Aurora&#x20;
* Avalanche&#x20;
* Base&#x20;
* BEVM&#x20;
* BEVM Canary&#x20;
* Beam
* Bifrost
* Bitgert
* BitTorrent&#x20;
* Blast&#x20;
* Boba&#x20;
* BSC&#x20;
* Callisto&#x20;
* Canto&#x20;
* Celo&#x20;
* Combo&#x20;
* Conflux&#x20;
* CoreDAO&#x20;
* Cronos&#x20;
* Degen&#x20;
* Dexalot&#x20;
* DFK&#x20;
* Dogechain&#x20;
* EOS EVM&#x20;
* ETC&#x20;
* Ethereum&#x20;
* Evmos&#x20;
* Fantom&#x20;
* Filecoin&#x20;
* Flare&#x20;
* Fraxtal&#x20;
* f(x)Core&#x20;
* Fuse&#x20;
* Fusion&#x20;
* Gelios&#x20;
* Gnosis&#x20;
* Harmony&#x20;
* HECO&#x20;
* Horizen EON&#x20;
* Hychain&#x20;
* Hypr&#x20;
* Immutable zkEVM&#x20;
* IoTeX&#x20;
* Kava&#x20;
* KCC&#x20;
* Klaytn&#x20;
* Kroma&#x20;
* Lambda&#x20;
* LightLink&#x20;
* Linea
* Loot&#x20;
* Lukso&#x20;
* Lumio&#x20;
* Mantle&#x20;
* Manta&#x20;
* Merlin&#x20;
* Metal&#x20;
* Meter&#x20;
* Metis&#x20;
* Mode&#x20;
* Moonbeam&#x20;
* Moonriver&#x20;
* Muster Network&#x20;
* MXC zkEVM&#x20;
* Nahmii&#x20;
* Neon EVM&#x20;
* Oasis&#x20;
* Oasys&#x20;
* OKX&#x20;
* opBNB&#x20;
* Optimism&#x20;
* Orderly&#x20;
* Pego&#x20;
* PGN&#x20;
* Play Apex&#x20;
* PlatON&#x20;
* Polygon&#x20;
* Polygon zkEVM&#x20;
* Pulsechain&#x20;
* Rari&#x20;
* Re.al&#x20;
* Rollux&#x20;
* RSS3&#x20;
* SatoshiVM&#x20;
* Scroll&#x20;
* Shibarium&#x20;
* Shiden&#x20;
* ShimmerEVM&#x20;
* Songbird&#x20;
* Step&#x20;
* SX Network&#x20;
* Syndicate Frame&#x20;
* Telos&#x20;
* Tenet&#x20;
* Tron&#x20;
* Ultron&#x20;
* Viction&#x20;
* VinuChain&#x20;
* Wan&#x20;
* WEMIX&#x20;
* XAI&#x20;
* XPLA&#x20;
* zkAmoeba&#x20;
* zkFair
* zkLink Nova&#x20;
* zkSync Era&#x20;
* Zeta&#x20;
* Zora


# FAQ

#### I'm not able to submit the approval transaction even after getting my gas loan, what do I do?

You most likely did receive the gas loan but your wallet has not updated or refreshed your balance quickly enough. Try closing out your wallet and restarting, then connect to SmolRefuel and follow the same steps as you did before.

#### I bridged some gas to another chain but still haven't received it yet, is it lost?

Don't worry, your funds are not lost in the void. Our 3rd party bridge provider may have intermittent issues causing a delay in your bridging, you should be getting your funds soon.

#### What is the minimum amount I can swap?

$2 is the minimum amount required to do a refuel swap

#### If you need additional assistance, join our [discord](https://discord.smolrefuel.com/) and submit a support ticket!


# Support/Contact

Send us a [DM on twitter](https://x.com/smolrefuel) or [join our discord](https://discord.smolrefuel.com/)


# Audit

View our smart contract audit completed by the Pashov Audit Group here

{% file src="/files/OnapCT7essyP2yYXU3bZ" %}