v20 (latest stable)

Status

Live August 17, 2026

Summary

This API release extends marketplace support to Base alongside Polygon: teams now hold multi-chain wallets, and Base listings, quotes, orders, holdings (including native USDC and carbon credits), and Circle wallets are fully supported. Holdings can also be fetched for multiple wallet addresses in a single request, and Toucan certificates now work on both chains, with native ICR certificates supported.

Release notes

General

• Extended Base support: Base marketplace listings, holdings, listing quotes/orders, and Circle wallets

• Teams now support multi-chain wallets (Polygon + Base) instead of a single wallet

• Holdings can be fetched for multiple wallet addresses in one request, including Base native USDC and Base carbon credits

• Toucan certificates work across Polygon and Base; native ICR certificates are supported

Endpoints removed

• None

Endpoints updated

GET /holdings/:address

• Now also returns Base chain holdings (native USDC and carbon credits)

• [⚠️BREAKING CHANGE] Polygon bridged USDC (usdc) holdings are no longer returned — only native USDC per chain

GET /listings

• Now returns listings from both Polygon and Base marketplaces

• Added sellerWallets query parameter (array of addresses)

• [⚠️DEPRECATED] sellerWallet is deprecated; prefer sellerWallets

GET /listings/:id

• Added optional network query parameter (polygon | base; defaults to searching both)

GET /teams/:id

• Added optional poll query parameter (true syncs wallets states)

POST /quotes

• Supports Base marketplace listing asset_price_source_id values (e.g. listing-8453-<listingId>)

POST /orders

• Supports Base marketplace listings

GET /retirements/:id/certificate

• Certificate generation supports Base Toucan and native ICR retirements

Endpoints added

GET /holdings

• Get holdings for one or more wallet addresses via the addresses query parameter

• Returns Polygon and Base native USDC plus carbon credit holdings

New optional query parameters

• None

Migration Path

• Listings

  • Replace the sellerWallet parameter with sellerWallets