How to print your own ecash, using Gandlaf's money printer brrr.gandlaf.com
To celebrate the recent money printer update, here is a short guide on how to use it.
Step 1: Go to the money printer
Unlike the FED's money printer, this Cashu ecash money printer is openly available. Head over to https://brrr.gandlaf.com to give it a spin.
Select a mint
Choose a mint that should be backing the ecash notes. You have a few different options when choosing a mint:
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Connect to your own mint: Connecting to your own mint is great if you want to be the backer of the ecash notes. It does however require you to have your mint up and running. You can connect to it by typing the mint URL into the input field.
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Connect to a known mint: There are mints that are already indexed on nostr. You can find them by clicking on the `discover more mints` button.
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Connect to any mint you want!: All you need is the mints URL. Just type it into the input bar!
Once you selected a mint, click connect to set up the mint for money printing :
After connecting to the mint, you will have the option to select the currency you want to print. Not all mints support all currencies! The dropdown menu below will show all available currencies the mint offers.
After selecting your preferred currency, click confirm to continue.
In the next step, you will chose the amount that should be printed on each note. Be careful though, because unfortunately not every amount is possible. To preserve mint users privacy ecash mints use fixed coin amounts. This means a specific amount, will be made up from smaller amounts. Today, most cashu mints use power-of-2 amounts.
So if you for example would like to print the amount "100", it would be made up from the coins [64, 32, 4]. The maximum number of coins that can be encoded in a QR code, without the QR code losing its readability is ~4. The money printer will analyze which amounts the mint offers, and show how many coins will be needed.
Below, you will see the calculation of how much the total issuance for this printing cycle will be. Once you are all set, click confirm to continue.
You can now either add the funds for the print via Cashu token or via Lightning. Let's first take a look on how to add funds via Cashu token.
If you select this option, I will assume that you already own ecash from the mint you wish to print the notes. Otherwise, you should move on to the payment by lightning.
You have to make sure that the token you are pasting is from the correct mint, in the correct unit/currency and matches the amount exactly! Otherwise, it will not work.
If you don't own ecash from that mint, you can pay for the print with lightning directly. The only fees that will be charged are Lightning network fees.
Just scan the QR code that is presented to you and wait for the payment to be confirmed.
Once the payment has confirmed, either through Cashu or through Lightning, the print is ready. You can now customize the design you wish to print.
You can select a color, a brand image and a corner image that should be put on the note.
Once you are happy with the design, go ahead and click `Print now! BRRRRRRRRRRR`
This will take you to the print page. You can now print the ecash by pressing `CTRL`+`P`
And that's it! You have now printed your own money. I hope you liked the experience of playing FED for a day.
Be aware! Once scanned and redeemed, the ecash notes become invalid. So they are one-time-use.
If you want to make another print, just refresh the page. It will take you back to the beginning. Your past prints will also be stored in the browser cache, so you can come back to them at a later time, if your printer overheated or something.
Happy printing!
@Gandlaf21