Release Notes - Developer Services - 2025

Added support for Avalanche and Unichain to Paymaster v0.8.

Updated the following documentation to reflect Avalanche and Unichain support in Paymaster v0.8:

• Paymaster Overview
• Paymaster Addresses and Events

Added support for USDC bridge to native upgrade for Sonic.

Added CCTP V2 support for Sonic.

Added the following documentation on Sonic support:

• Quickstart: Set up and Transfer USDC on Sonic

Updated the following documentation to reflect Sonic support:

• CCTP Supported Blockchains
• CCTP Required Block Confirmations
• CCTP Contract Addresses and Interfaces

Added Paymaster v0.8 documentation.

Updated the following pages to reflect support for EntryPoint v0.8 of the ERC-4337 contract in Paymaster:

• Paymaster Overview
• Quickstart: Build a Wallet to Pay Gas Fees with USDC
• Paymaster Addresses and Events

Added passkey recovery support to Modular Wallets Web SDK.

Added the following documentation to support passkey recovery using the Modular Wallets Web SDK:

• How To Set Up Passkey Recovery.

Updated the following documentation to support passkey recovery in Modular Wallets:

• Modular Wallets Web SDK:
  • Added estimateExecuteRecoveryGas function.
  • Added estimateRegisterRecoveryAddressGas function.
  • Added executeRecovery function.
  • Added recoveryActions function.
  • Added registerRecoveryAddress function.
• Modular Wallets Passkey

Updated the following documentation to reflect the removed API and the new Derive a Wallet API endpoint:

• Programmable Wallet API Rate Limits

• Removed API for products that never officially launched. The following APIs were removed:

  • Backfill a Wallet API: PUT /developer/wallets/:id/backfill

• Added content schema, description, and the X-Request-Id header to the 201 response for the following APIs:

  • POST /v1/w3s/user/initialize
  • POST /v1/w3s/user/pin
  • PUT /v1/w3s/user/pin
  • POST /v1/w3s/user/pin/restore
  • POST /v1/w3s/user/wallets
  • POST /v1/w3s/user/transactions/{id}/accelerate
  • POST /v1/w3s/user/transactions/{id}/cancel
  • POST /v1/w3s/user/transactions/walletUpgrade

• Added the new Derive a Wallet API: PUT /developer/wallets/:id/blockchains/:blockchain

• Launched Developer Services, including Circle Contracts, on Optimism (OP) and Base (BASE) blockchains.
• Added Modular Wallets and Circle Contracts support on Unichain (UNI) blockchain.
• Added a new tutorial in Modular Wallets to showcase how to add Externally Owned Account (EOA) signers for Circle Smart Accounts.

Added the following documents:

• Dynamic Integration Tutorial

Added Optimism (OP) and Base (BASE) blockchains to tables of support:

• Account Types
• Blockchain Compatibility for Developer Services APIs
• Blockchain Confirmations
• Gas Fees
• Gas Station
• Gas Station Contract Addresses
• Gas Station Policy Management
• Modular Wallets Android SDK
• Modular Wallets iOS SDK
• Modular Wallets Quickstart
• Receive an Inbound Transfer (User-Controlled Wallets)
• Receive an Inbound Transfer (Developer-Controlled Wallets)
• Send a Gasless Transaction
• Supported Blockchains and Currencies
• Testnet Faucets

• Added enum values BASE, BASE-SEPOLIA, OP, OP-SEPOLIA to the blockchain request field for the following APIs:

  • POST /developer/wallets
  • POST /user/wallets
  • GET /wallets
  • GET /transactions
  • POST /transactions/contractExecution/estimateFee
  • POST /transactions/transfer
  • POST /transactions/transfer/estimateFee
  • POST /transactions/validateAddress
  • POST /user/initialize
  • GET /config/entity/monitoredTokens
  • GET /contracts
  • POST /contracts/deploy
  • POST /contracts/deploy/estimateFee
  • POST /contracts/import
  • POST /contracts/query
  • POST /templates/{id}/deploy
  • POST /templates/{id}/deploy/estimateFee
  • GET /contracts/monitors
  • POST /contracts/monitors
  • GET /contracts/events

• Added enum values UNI and UNI-SEPOLIA to the blockchain request field for the following APIs:

  • GET /contracts
  • POST /contracts/deploy
  • POST /contracts/deploy/estimateFee
  • POST /contracts/import
  • POST /contracts/query
  • POST /templates/{id}/deploy
  • POST /templates/{id}/deploy/estimateFee
  • GET /contracts/monitors
  • POST /contracts/monitors
  • GET /contracts/events

Launched the SDK Explorer for Developer Services server-side SDKs.

Added the following pages for the SDK Explorer:

• SDK Explorer Overview
• Getting Started with Developer-Controlled Wallets - Node.js
• Getting Started with Developer-Controlled Wallets - Python
• Getting Started with User-Controlled Wallets - Node.js
• Getting Started with User-Controlled Wallets - Python
• Getting Started with Contracts - Node.js
• Getting Started with Contracts - Python

The following Circle Product Lines have been renamed:

The following Circle Products have been renamed:

These name changes are part of a broader effort to simplify and align our product naming, creating a more unified developer experience across the Circle platform.

Updated the following document to reflect the new Backfill a wallet API endpoint:

• Programmable Wallet API Rate Limits

Added new API endpoints:

• GET /v1/w3s/developer/wallets/balances
• PUT /v1/w3s/developer/wallets/{id}/backfill

Removed USDC Access from the developer documentation as it's no longer available for new users.

• Updated description for the following APIs:

  • POST /developer/sign/message
  • POST /developer/sign/typeData
  • POST /user/sign/message
  • POST /user/sign/typeData

• Added example for Address and ContractAddress

• Updated abiFunctionSignature to be optional for the POST /transactions/contractExecution/estimateFee API.

• Added enum values UNI and UNI-SEPOLIA to the chain request field for the following API:

  • POST /compliance/screening/addresses

Added EIP-1193 example for Modular Wallets

Added a code example for EIP-1193:

• Key Features

Launched Web3 Services on Unichain mainnet

Added Unichain mainnets to tables of support:

• Supported Blockchains and Currencies
• Blockchain Compatibility for Web3 Services APIs
• Blockchain Confirmations
• Gas Fees
• Gas Station Contract Addresses
• Gas Station

Added information on batching user-ops with the Circle API.

Updated information on batch operations:

• Account Types
• Batch Operations

• Added enum value UNI to the blockchain request field for the following APIs:

  • POST /developer/wallets
  • POST /user/wallets
  • GET /wallets
  • GET /transactions
  • POST /transactions/validateAddress
  • POST /user/initialize
  • GET /config/entity/monitoredTokens
  • POST /developer/transactions/transfer
  • POST /transactions/transfer/estimateFee
  • POST /user/transactions/transfer
  • POST /user/transactions/transfer/estimateFee

Launched User-Controlled Wallets signing on EVM chains.

Added information for signing transactions with User-Controlled Wallets:

• Confirmation UIs
• Signing APIs
• Supported Blockchains and Currencies

• Updated the description of error code 155236: The provided fee in request is invalid.

Launched Modular Wallets.

Added Modular Wallets content to the Programmable Wallets section of the Web3 Services pillar:

• Modular Wallets Quickstart
• Modular Wallets SDKs
• Modular Wallets Sample App

Added Modular Wallets endpoints:

• GET buidl/transfers
• GET buidl/userOps
• GET buidl/wallets/balances
• GET buidl/wallets/nfts

Launched Web3 Services on Unichain testnet.

Added Unichain testnet to tables of support:

• Supported Blockchains and Currencies
• Blockchain Compatibility for Web3 Services APIs
• Blockchain Confirmations
• Gas Fees
• Gas Station Contract Addresses
• Gas Station