If you work in payments, you know the pain. You've sent the payment. The customer says it never arrived. You're now combing through transaction hashes trying to figure out which onchain transfer corresponds to which invoice. But @Arc just shipped something that fixes this: Transaction Memos are now live on Arc Testnet. Here's what that actually means: Every payment rail in traditional finance has some form of structured reference (like an invoice number). Onchain payments have never really had this in a native way. Memo-enabled calls change that: → Attach invoice IDs, payout references or customer IDs directly to a contract call → Preserve sender attribution at the protocol level → Memo events only emit when the contract call actually succeeds This sounds like a small feature but it's not. It's the difference between a payment that says "0.5 ETH moved from address A to address B" and a payment that says "Invoice #4471#, paid in full, from this customer, confirmed onchain." That's the gap between crypto rails and actual financial infrastructure. Most chains weren't built with this kind of operational context in mind because they weren't built for enterprises. But Arc is. This is what building for the way money actually moves looks like.