FeesaSwap

Overview

FeesaSwap is a payment tool that lets you cover Cardano network fees with any supported token in your wallet, instead of having to keep ADA on hand just to make transactions. You sign a transaction using the token you already hold, FeesaSwap swaps a small slice of it for ADA behind the scenes, pays the fee, and submits the transaction in a single step¹. It is also built for other wallets and apps to plug in, so users get the same convenience without leaving the place they already use.

Every Cardano transaction needs a tiny amount of ADA to cover its network fee. Someone who arrives holding only a project token, a stablecoin, or an NFT royalty normally has to stop, visit an exchange, and buy enough ADA before they can do anything else. FeesaSwap removes that detour. It is built by MLabs, a long-running Cardano development firm, and runs on Cardano mainnet on top of an on-chain contract referred to in the project's documentation as Pisa².

Key Features

• One-step payment in your token. You sign a transaction using a supported token, and FeesaSwap converts just enough of it into ADA, settles the network fee, and submits the transaction. There is no separate swap step and no need to top up ADA first¹.
• Shared liquidity for the whole ecosystem. Liquidity providers post a single position to a public on-chain pool, and any wallet or app that has added FeesaSwap can draw on that same pool. Builders do not have to maintain a private fee fund per project³.
• Drop-in component for builders. Apps can install @mlabs-haskell/feesaswap-components, a ready-made interface piece that handles wallet selection, the swap, and submission in a few lines of code⁴.
• SDK for non-React stacks. A separate developer kit offers the same functionality for projects that are not built in React, so a wider range of apps can offer the feature without rebuilding the logic.
• Test networks supported. The component works on Cardano mainnet and on the preprod and preview test networks, so teams can try things out before going live⁴.

What to Expect

The homepage at feesaswap.io is a single page aimed at developers. It walks through a three-step explainer, offers a Connect Wallet demo to try, and shows a code snippet for embedding the component¹. Listed wallets include Lace, Eternl, and VESPR, with more noted as coming. For everyday users, the experience usually shows up inside an app or wallet that has already added FeesaSwap: paying a fee feels normal, except the wallet displays the fee in the token being used instead of asking for ADA.

For people building on top of it, the integration guide walks through how an app prepares an unbalanced transaction, picks a liquidity position, sends it to the FeesaSwap balancer service, and signs and submits the result². The user-facing component and SDK are open source under the MIT license. MLabs has stated in its Project Catalyst Fund 15 proposal that the protocol is being arranged for an external CertiK audit, though a public audit report has not yet been identified⁵.