Disclaimer: The author is NOT a cryptographer and this work has not been reviewed. This means that there is very likely a fatal flaw somewhere. Cashu is still experimental and not production-ready.

Don't be reckless: This project is in early development; it does, however, work with real sats! Always use amounts you don't mind losing.

This project is in active development; it has not gone through optimization and refactoring yet.

Nutmix

Cashu protocol mint focused on ease of use and feature completeness.

Please test in Mutinynet at: https://mutinynet.nutmix.cash

Purpose of this project

I saw the work made by calle on the Cashu protocol and was fascinated by the awesomeness of the project. So I decided to make an implementation of the mint in Go.

I'm also attempting to make all NUTs available as well as some other ideas such as: Monero and FIAT ecash.

Supported NUTs

Implemented NUTs:

• [x] NUT-00
• [x] NUT-01
• [x] NUT-02
• [x] NUT-03
• [x] NUT-04
• [x] NUT-05
• [x] NUT-06
• [x] NUT-07
• [x] NUT-08
• [x] NUT-10
• [x] NUT-11
• [x] NUT-12
• [ ] NUT-13
• [x] NUT-14
• [x] NUT-15

Objective

Build the fastest and most secure implementation of an ecash mint possible. This would include and admin dashboard to be able to monitor and control de behaviour of the mint.

Roadmap

At this moment NUTS are up to P2PK (NUT-11) are implemented and working. I plan to keep going until all NUTS are done.

1. Finish Milestones for V1.
2. Finish NUTS until NUT-15.
3. Add dashboard for controlling aspects of the mint.
   • Nostr Login
   • Rotate keysets.
   • Monitor Mint activity.
   • Emmit blind signatures for certain users.
   • Activate Nostr only mode.
   • Change mint messages
4. Add support for other lightning nodes. Ex: core-lighting, Strike, Greenlight.
5. Add Monero Support this would probably include a way to exchange in between Bitcoin and Monero.
6. Tor only mode
7. Nostr only Mode.
8. Remote signing. This would leave the mint in a highly available server but the lightning transactions and tokens would be signed and verified on a secure enclave. This could be something like a hardware device or AWS Nitro. I would probably take inspiration or directly use something like VLS

Run the Mint

This project is thought to be able to be ran on a docker container or locally.

Here is what you need to know to change to run nutmix in docker: Most of the setup process will happen inside the Admin dashboard.

You'll need the correct variables in an .env file first. Use the env.example file as reference.

• You need to make sure to use a strong POSTGRES_PASSWORD and make user the username and password are the same in the DATABASE_URL

• Add you mint in: MINT_PRIVATE_KEY. Please use a secure Private key.

• To login into the admin dashboard and change the rest of settings add your npub to ADMIN_NOSTR_NPUB.

The mint will fail and Print out what you are missing if you don't have this 4 Items setup.

You can now login and setup your Lightning node and Mint information. It's important to set up the variables under LIGHTNING CONNECTION for connecting to a node.

if you want to run with docker traefik and you also need to fill variables below HOSTING for your domains.

If you have this correctly setup it should be as easy as running a simple docker command on linux:

docker compose up -d

How to rotate a keyset up

Login to the admin dashboard and click the rotate button on the keyset sections.

Development

If you want to develop for the project I personally run a hybrid setup. I run the mint locally and the db on docker.

I have a special development docker compose called: docker-compose-dev.yml. This is for simpler development without having traefik in the middle.

1. run the database in docker. Please check you have the necessary info in the .env file.

docker compose -f docker-compose-dev.yml up db

2. Run the mint locally.

# build the project go run cmd/nutmix/*.go

Support

Pull requests and suggestions are always welcomed. The more people have eyes on this the better.

If you can donate monetarily it would be greatly appreciated. The funds would go to the development of the mint and servers for testing.

on-chain silent payments

sp1qq0fju879lh2rgvwjjd7e78pg4gnr7a8aumth8qlezdgjs2rwzk7ssq5jm7v27cuuk5dyjfurdy8t8jflkcx0sluwez350kjjd45y7nnx3vgmjqjq

Donate with lightning

nutmix@npub.cash

Donate with on-chain

bc1qp7lswgftpgrkt00vszrm63dmkq3nuxjv60czk6

Donate with Monero

84yCRZY6BXebs8xWE6Yzj6S6cE17uLhkTSynneVPmejjWAcgBtnV7UEUiZqJNLE4pXaPmXNkJuhcAYbpu49zAdVsEZqqxac