This feels so nice.
Paid for a group of friends to see Monkey Man later today and just told everyone to zap me. No invoices, no sending everyone payment details, no need to be online, just "zap me"
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Awesome! Recently, I joined one of the recommended Federations and tested some payments. Works nice! But I wonder why the Federation I picked has an expiry date? Is the duration always limited? What is the benefit of letting a Federation expire?