Feature Requests

Hey team, I wanted to suggest a much-needed improvement for the 0x API: native support for ERC-2612 permit signatures. Right now, you support Permit2—but let’s be honest, it's messy, overcomplicated. The whole point of ERC-2612 is enabling true gasless approvals with unlimited allowance via signature. Permit2 still requires a one-time on-chain approval, which kind of defeats the purpose—it's not really a gasless solution. For reference: 1inch does this right. When selling tokens like 1INCH through their aggregator, they support native ERC-2612 permit directly. No extra overhead, no on-chain approval needed just to sell—it’s clean, efficient, and exactly the UX users expect. It would be awesome if the 0x API could support the same behavior. Even rolling it out for major ERC-2612 tokens at first would already make a huge difference.

I’d like to request the addition of the Sonic chain (formerly Fantom, chain ID 250) to the list of supported networks for the 0x Swap API. Sonic is an EVM-compatible Layer-1 blockchain that recently rebranded from Fantom, offering high performance (10,000+ TPS) and sub-second finality, making it a growing hub for DeFi activity.

Solana has the spotlight as the preferred chain for new tokens to launch on. If possible, can you consider adding support for it in the Price & Swap API?

In v1 of the Swap API, the estimatedPriceImpact parameter was a helpful metric for understanding potential slippage and trade execution risk. However, this parameter appears to be missing in v2. This impacts our ability to communicate trade quality to users and to implement safeguards for high-impact trades. Adding estimatedPriceImpact to v2 would provide integrators with a consistent and critical metric for UX, risk management, and transparency — especially in volatile or low-liquidity markets. We would appreciate this parameter being reintroduced in v2.

I’d like to request the addition of the Linea chain (59144) to the list of supported networks for the 0x Gasless API

I’d like to request the addition of the Sonic chain (formerly Fantom, chain ID 250) to the list of supported networks for the 0x Swap API. Sonic is an EVM-compatible Layer-1 blockchain that recently rebranded from Fantom, offering high performance (10,000+ TPS) and sub-second finality, making it a growing hub for DeFi activity.

Please deploy the 'BatchFillNativeOrdersFeature' contract for the 'exchangeProxy' on the Sepolia testnet so that the 'batchFillLimitOrders' method on the 'exchangeProxy' can be used just like on Goerli.

weETHs is routed on 0x protocol however the route is not optimal. There is liquidity on Curve for the token but 0x is not taking it into account. Can you please add that pool aswell? weETHs: 0x917cee801a67f933f2e6b33fc0cd1ed2d5909d88 Curve Pool: 0xb92b054b9cc33685e7f8c3f85177c4b6dc061391

Hello. I am the creator of nullfinance.com using 0x protocol. I would like to request you to add a new mainnet. The mainnet name is hela chain and the main ID is 8668. (Testnet ID is 666888.) https://docs.helalabs.com/build-on-us/hela-network-information Thank you.

I would like to request the addition of support for the Canto blockchain in the 0x Swap and Price API. Canto is a permissionless, general-purpose blockchain running the EVM. It was specifically designed to fulfil the promise of decentralized finance (DeFi) by creating new systems that are accessible, transparent, decentralized, and free. Key Features: Uniswap V2 DEX: Canto has a robust DEX built on the Uniswap V2 protocol, which is widely recognised and trusted in the DeFi community. Solidly for Stable Pairs: For stable pairs, Canto integrates Solidly, providing efficient and reliable trading mechanisms for stable assets. Ambient Pools: The Canto ecosystem also supports ambient pools, further enhancing liquidity and trading efficiency across various asset pairs.