[Sem_pre]

The nonce serialization problem is real — cache locks work but get hairy at scale, especially if you need concurrent payouts.

For the verification side (confirming stakes arrived), you might consider separating that from your sidecar entirely. Watching the chain for a specific USDC amount + matching it to an intent is a well-defined problem that doesn't need to live in your app logic.

I'm building something in this space (PayWatcher — verification-only, non-custodial, $0.05 flat on Base). Would have saved you the transfer event parsing at least. Curious how you handle confirmation edge cases like reorgs.