DeFi software firm 0x released an application programming interface, or API, that allows exchanges to abstract gas fees away from users. The so-called Tx Relay software was previously used in beta by platforms including Robinhood and Coinbase to enable “gasless swaps.”
Users still pay for gas with 0x’s API, but the software lumps the fee into the trade cost to reduce the number of failed trades. Tx Relay is emblematic of a larger shift from many developers toward intents-based systems that outsource some on-chain actions to protocols.
0x sells APIs focused on decentralized exchange (DEX) infrastructure. The San Francisco-based firm has notable venture ties, raising a $70 million Series B in 2022 led by Greylock with participation from Pantera, Brevan Howard and Coinbase Ventures.
Robinhood’s crypto wallet began using Tx Relay API as early as March 2023. At the time, 0x said the software would make onboarding easier by obscuring gas fees and protecting users from maximal extractible value (MEV). Arbitrageurs making use of MEV can frontrun users’ transactions to profit off of things like price slippage.
Matcha, a DEX aggregator built by 0x, also used Tx Relay in its beta phase, as did Coinbase for its wallet. 0x says Matcha was able to reduce failed trades by 85% compared to competitors after rolling out Tx Relay-based “Matcha Auto.”
“Gasless swaps have helped us create a simpler trading experience, where users can focus more on trading and less on network fees,” Coinbase wallet production manager Claudia Haddad said in 0x’s documentation on the API.
DeFi has lately seen a UX-focused shift toward intents-based systems, where users will say what trade they want to execute but not necessarily how the trade should happen. Instead of dealing with wrapped tokens or gas fees, users can tell a protocol to swap one token on one chain for a different token on another chain and let the software handle the rest.
The marquee DEX Uniswap dipped its toes into intents with the release of UniswapX. The protocol uses an auction process to execute intent-based gas-free swaps.
Tx Relay is similar in consequence to intent-based systems, Theo Gonella, 0x’s director of product management, said in a direct message.
“[I]t’s basically an intent based system with one single solver (0x, which fetches best AMM prices and connects to leading DEX Market Makers),” Gonella wrote. Solvers are the entities that carry out user intents in a blockchain context.
Intents pare down the number actions users need to take on-chain. Obvious questions emerge as to who is handling the intents and what they do behind the scenes — but many see intents-based systems as a necessity to make crypto user-friendly.
“Almost nothing about the current blockchain UX will be acceptable for broader adoption,” Kevin Weaver, backend engineer at blockchain platform Metropolis, said in a text. “As long as an intent is designed in a way that doesn’t introduce new trust assumptions, I’m a fan of doing whatever we can to smooth out the rough edges.”