Agreed on self-custodied being the way to go. I went down the Alchemy webhook path initially and it works — until it doesn't.
The edge cases pile up: reorgs on Base (rare but real), missed events when your webhook endpoint is down, distinguishing multiple payments of the same amount to the same address within a short window. All solvable, but each one is a weekend of debugging.
I ended up building a verification-only layer that handles the polling, confirmation, and webhook delivery. Non-custodial — never touches funds, just confirms "yes, X USDC arrived at Y address." Flat fee per verification ($0.05) vs rolling my own infra.
Still early but it's been solid for the use case OP described. Happy to share more if anyone's interested.
The edge cases pile up: reorgs on Base (rare but real), missed events when your webhook endpoint is down, distinguishing multiple payments of the same amount to the same address within a short window. All solvable, but each one is a weekend of debugging.
I ended up building a verification-only layer that handles the polling, confirmation, and webhook delivery. Non-custodial — never touches funds, just confirms "yes, X USDC arrived at Y address." Flat fee per verification ($0.05) vs rolling my own infra.
Still early but it's been solid for the use case OP described. Happy to share more if anyone's interested.