A gas fee is a transaction fee that is associated with a blockchain transaction, deducted in the network protocol's native token. A Gas Station is a type of a wallet used to pay the gas fee by refilling wallets (hot, warm, and cold wallets) containing only tokens. This eliminates the need to refill the individual wallets with native coins.

Liminal offers a Gas Station feature that automatically refuels the MPC deposit wallets with the required amount of native coins. This is done when these wallets are low on native coins below the defined threshold. Gas Station is created at the time of creating a new organisation for your Virtual Asset Service Provider (VASP) on a Liminal platform. A single Gas Station is created for each protocol. For instance, one Gas Station is created for Ethereum (ETH), and one for Binance Smart Chain (BSC). Currently, Liminal only supports the Gas Station feature for all EVM-based protocols.

If the Gas Station balance is insufficient to pay the gas fee for the amount of transaction from a deposit wallet, the transaction will not be executed. You must consistently refill and maintain sufficient balance of native coins in your Gas Station to ensure uninterrupted transactions from your wallets.

Gas Station features

The key features of Gas Station are as follows:

Final signer: For a multisig wallet transaction, Gas Station acts as the final signer after all policy checks are completed. Additionally, the gas fee is also deducted directly from Gas Station.
Refill MPC wallets: You can update the Gas Station rules to refill MPC wallets with native coins to ensure uninterrupted token transactions. For more information, see Update Gas Station rules.
Refill Sprayer: In case of deposit wallets, you can set Gas Station to add assets to Sprayer automatically, which in turn sprays/sends the assets to the addresses of a deposit wallet. To learn about Sprayer, see Sprayer wallet.
View transaction logs: You can view all transaction logs in Liminal Vaults. For more information, see View transaction logs.

The following flowchart illustrates the movement of assets from Gas Station.

Sprayer

Sprayer is an extension to Gas Station but functions as a separate wallet. It is designed to refill individual addresses of the deposit wallet. Gas Station automatically refills Sprayer and then Sprayer automatically sprays assets to the addresses of your deposit wallet. It sends native coins to the addresses whenever they are low on minimum required native coins. This enables smooth consolidation of tokens from the addresses to the destination wallet. You must ensure that Gas Station is sufficiently full.

When a deposit wallet is created, a rule to refill Sprayer from Gas Station is automatically configured for your organisation.

Set up the Gas Station rules

Liminal sets up a default Gas Station for your organisation. However, you, as an owner or admin of your organisation, can enable and modify the Gas Station rules in Liminal Vaults as per your requirements.

You can perform the following actions in Liminal Vaults:

Solana Gas Station

Solana Gas Station is designed to store and automatically distribute native SOL assets to your Solana deposit wallet addresses, ensuring they have sufficient balance of native SOL assets for consolidation transactions. Additionally, it monitors the remaining balances of addresses after consolidation transactions and automatically sends the rent amount if any balance is below the minimum threshold, to avoid account closure. To learn more about rent, see Rent.

Important: Unlike the standard Gas Station which includes two components–Gas Station (for refilling) and Sprayer (for distributing native coins to deposit wallet addresses), Solana Gas Station currently only features Sprayer. However, Liminal is in the process of implementing a Gas Station for Solana. For now, you need to directly refill Solana Sprayer which is available in the Wallets section of Vaults.

To enable Solana Sprayer for your organisation in Vaults, reach out to the Liminal support team at [email protected].

To learn how to refill Solana Sprayer see Refill Solana Sprayer.

Note: Reach out to the Liminal support team at [email protected] if your Gas Station is not visible in the Liminal Vaults UI.