LNURL & Lightning Addresses

What does a wallet do first when you type a Lightning address?

• Opens a payment channel to the domain
• Fetches a fixed web address on that domain built from the username
• Asks a Nostr relay for the recipient's invoice

Why does the wallet compare the invoice amount with the amount you chose?

• To work out the routing fee
• Because invoices are always in sats and the request is in millisats
• So a server can't bill you a different amount from the one you picked