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/
