Transaction memos are now available on Arc Testnet. In this Release Notes episode, Blessing from Circle DevRel explains how to send USDC with a transaction memo and how transaction memos bring structured context to onchain financial activity. Transaction memos let builders attach structured context to individual contract calls on Arc, including existing contracts like USDC, without modifying them. This makes payments, payouts, and batched flows easier to reconcile, attribute, index, and connect to internal systems. This episode covers: - How to encode the inner ERC-20 transfer call - How to call the memo function on the Memo contract with memoId and memoData - How to decode the emitted BeforeMemo and Memo events - How to query memo events later by memoId - Why preserving the original sender and only emitting on success matters for offchain systems - The current Arc Testnet limitation for smart contract wallets Resources: Docs tutorial: https://docs.arc.io/arc/tutorials/send-usdc-with-transaction-memo Blog post: https://www.arc.io/blog/arc-transaction-memos-structured-context-for-onchain-transactions Explore more content for building on Circle and Arc: https://developers.circle.com/ https://docs.arc.network/

In episode 8 of our Arc 101 series, we walk through how to transfer USDC from one wallet to another on Arc Testnet using Circle Developer-Controlled Wallets. You’ll learn how to: • Set up a Node.js project with the Circle SDK • Create two developer-controlled wallets on Arc • Fund a wallet with USDC • Transfer USDC between wallets • Check the transaction status through the API • Verify the completed transfer on the Arc block explorer Arc is an open L1 blockchain launched by Arc Network Services LLC ("Arc LLC") and operated by a permissioned validator set. Arc LLC provides software services only and does not offer regulated financial or advisory services. Arc has not been reviewed or approved by the New York State Department of Financial Services or any other regulatory authority. The Arc network is provided "as is" and "as available." Use of Arc involves inherent risks associated with blockchain technology, including smart contract vulnerabilities, network disruptions, and the absence of recourse for transaction errors or losses. The ability to transact on Arc depends on the ability to obtain and use USDC to pay gas fees. Neither Arc LLC nor any permissioned validator is responsible for the content, accuracy, legality, or functionality of third-party applications, protocols, or services built on or integrated with Arc. You are solely responsible for features or services you provide to users, including obtaining any necessary licenses or approvals and otherwise complying with applicable laws. All Arc features may be modified, delayed, or cancelled at any time without notice. Nothing herein constitutes a commitment, warranty, guarantee or legal, regulatory, tax, or investment advice. Coming soon.

In episode 7 of Arc 101, we walk through the full smart contract lifecycle on Arc using Circle Contracts: • Create a wallet on Arc Testnet • Deploy an ERC-20 contract • Interact with contract functions • Track transaction status • Monitor onchain events through webhooks • Work with templates, open source payment protocols, or custom compiled contracts Arc testnet is offered by Circle Technology Services, LLC (“CTS”). CTS is a software provider and does not provide regulated financial or advisory services. You are solely responsible for services you provide to users, including obtaining any necessary licenses or approvals and otherwise complying with applicable laws. Arc has not been reviewed or approved by the New York State Department of Financial Services. The product features described in these materials are for informational purposes only. All product features may be modified, delayed, or cancelled without prior notice, at any time and at the sole discretion of Circle Technology Services, LLC. Nothing herein constitutes a commitment, warranty, guarantee or investment advice. Circle Contracts are provided by Circle Technology Services, LLC (“CTS”). CTS is a software provider and does not provide regulated financial or advisory services. You are solely responsible for services you provide to users, including obtaining any necessary licenses or approvals and otherwise complying with applicable laws. For additional details, refer to console.circle.com/legal/developer-terms for the Circle Developer terms of service.