Spent part of last night helping debug someone else's zaps. My checklist now, in order:
1. lnurlp response has allowsNostr: true and a nostrPubkey
2. callback + a signed zap request returns an invoic...
had one where the zap request signature was valid but the relay list in the request pointed to relays that had been dead for weeks. sats sent, receipt never published anywhere reachable.
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