
Show HN: Paypyrus – Electronic money in physical form with Venmo - cydrobolt
https://github.com/cydrobolt/paypyrus
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leichtgewicht
So I only see two major downsides: 1) I basically I have to verify/transact
every "printed" money the moment I get it - preferably using a smartphone - in
case someone else has a copy of it and "takes" it first. Copies could be made
with any high-resolution camera. 2) If the money travels from A to B to C in
paper shape and the digital transaction will be from A to C then A will know
that B has done business with C.

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BHSPitMonkey
Unless the note changes hands additional times between B and C.

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leichtgewicht
Point taken. It then just becomes a statistical probability of how many steps
between A and N. Considering that everybody using this system better have 0
steps (former point made) 1 step is about the furthest I would hope. But you
are right: there could be more steps.

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vzaliva
It is unclear from description (and I am too lazy to read the code) how it
works.

The first question is whether such paper "bill" would guarantee payment. Could
issuer refuse to pay it, when presented. In other words such paper bill is
analogous to dollar bill or bank check? If this feature could not be
implemented with Venmo API, perhaps one can build some kind of escrow service.

My second question is about privacy. Is identity of the original paper bill
"issuer" is disclosed to recipient?

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yc1010
It would be similar to a cheque, central banks and governments do not like
normal people printing "money" or inventing their own

a better alternative would be bitcoin paperwallets, this here relies on Venmo
to play nice as well as the "payer"

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cydrobolt
Agreed. Using Bitcoin would definitely help make it resemble cash, however,
this could potentially be less convenient. Venmo is more popular among
students, especially on university campuses, so the idea was to make it easy
to adopt among friend groups, not specifically to guarantee the transfer of
funds.

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morgante
I actually made something pretty similar to this for Bitcoin. Basically
printed coins with the public key on the outside and the private key inside,
so you could verify that the "wallet" was full and then break it open once
you're ready to redeem.

In practice, it was only really useful as a gimmick/fun tool for giving people
their first bitcoin.

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stephentmcm
>Paypyrus is versatile like cash

But with none of the security, what a useful idea... Could I not just print
the same dollar twenty times then it's a race to see who redeems it first?
Cute idea though I guess.

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AbdulBahajaj
I think that they can add security features in the future.

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krasin

      $ cat /var/history.log | grep 'add.*security.*future' | grep -v failure | wc -l
      0

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dkroy
This is a hell of an idea. Haha, Damn you this has triggered my
entrepreneurial ADD, it makes me want to build something around it! Venmo
should not ignore this. They could really build upon this, and get some vendor
lock-in if it gains popularity among their already loyal users.

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exo762
This is just like printing out private keys for bitcoin wallet. AKA "paper
wallet".

