# ⋰·⋰ Feeless

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## What is Feeless?

**Feeless** is a **Nano** cryptocurrency node, wallet, tools, and Rust crate. This is not the official project for Nano,
only an implementation written in Rust. The official Nano node
implementation [lives here](https://github.com/nanocurrency/nano-node).

🚸 This is a work in progress. The API will probably change without notice until `v0.2`. 🚸

I decided to start this project as a personal adventure of understanding Nano. I give no promises about my future
motivation to complete this project 🤐.

## Documentation

Please visit the documentation website for general information, features, installation, CLI usage and more.

https://feeless.dev/

## What is Nano?

**Nano** is digital money that significantly improves on **Bitcoin** and other cryptocurrencies.

The main features of **Nano** are:

* No transaction fees.
* Extremely fast to send money—less than 1 second for 100% confirmation.

  <sup>
    Bitcoin takes 10 minutes on average for ~80%<sup>1</sup> confirmation.
    Nano is more asynchronous than Bitcoin—individual transactions are voted on separately from the rest of the network.
  </sup>
* Highly decentralized.

  <sup>Using the Nakamoto coefficient measurement, it is more decentralized than Bitcoin<sup>2 3</sup>.
* No inflation.
* Green—Massively less energy use than Bitcoin.

For more information on what Nano is, see the Nano documentation: https://docs.nano.org/what-is-nano/overview/

Nano is also known as: Nano cryptocurrency, Nano coin, RaiBlocks.

<sup>
1. The Bitcoin white paper, under section 11 "Calculations" explains there's a ~80% chance for an attacker with 10% mining power to overtake the longest chain. https://bitcoin.org/bitcoin.pdf
2. Measuring Decentralization in Bitcoin and Ethereum using Multiple Metrics and Granularities https://arxiv.org/pdf/2101.10699.pdf
3. List of representative nodes showing a Nakamoto coefficient of 8 at the time of writing (2021-02) https://nanocharts.info/

</sup>

## Task list

A medium term task list:

- [x] Seeds
    - [x] Mnemonic (word list) seed generation/parsing (BIP39)
    - [x] Derive keys from mnemonic (BIP33)
    - [x] Hex seeds
- [x] Keys (ed25519/blake2b)
    - [x] Private keys
    - [x] Public keys
    - [x] Nano addresses
        - [x] Validation
        - [x] Parsing
        - [x] Conversion to/from public keys
- [x] Nano amount conversions
    - [x] raw
    - [x] nano
    - [x] Mnano/NANO
- [x] Proof of work (core)
    - [x] Verification against a threshold
    - [x] Generation
    - [x] Dynamic threshold
- [ ] Blocks
    - [x] Hashing
    - [x] Work
    - [x] State blocks
    - [x] <v18 blocks
- [ ] Packet dissector
    - [x] Parse pcap file
    - [x] Dump some message types to console
    - [ ] Mark this done when all packets are decoded successfully (see below)
- [ ] Node
    - [ ] Configuration
        - [x] Initial command line interface
        - [ ] Network
        - [ ] Database
        - [ ] ...
    - [ ] Networks
        - [x] Live (Don't worry, I'm only connecting to my own node at the moment!)
        - [ ] Test
        - [ ] Beta
    - [ ] Bootstrap peer connection (peering.nano.org)
    - [x] Validate given peer network
    - [ ] Validate given peer versions
    - [ ] Multiple peer connectivity (currently only connects to one peer)
        - [ ] Configurable maximum peer limit
    - [x] Header parsing
        - [x] Network
        - [x] Versions
        - [x] Extensions
            - [x] Handshake query/response flags
            - [x] Count
            - [x] Block type
            - [ ] Telemetry size
            - [ ] Extended params present
    - [ ] Logic
        - [ ] Rebroadcasting
        - [ ] Representatives
        - [ ] Publish retries (difficulty changes)
        - [ ] Respond to telemetry request
        - [ ] ...
    - [ ] Messages
        - [ ] Node ID Handshake
            - [x] Serialize (TODO: needs small refactor)
            - [x] Deserialize
            - [x] Send cookie
            - [ ] Cookie/peer store and logic
            - [x] Validate response
            - [x] Validate signature
        - [ ] Confirm Req
            - [ ] Serialize
            - [x] Deserialize
                - [x] Hash pairs
                - [x] Block selector
            - [ ] Handle response
        - [ ] Confirm Ack
            - [ ] Serialize
            - [ ] Deserialize
                - [x] Vote by hash
                - [ ] Block
            - [x] Validate signature
        - [ ] Keepalive
            - [ ] Serialize
            - [x] Deserialize
        - [ ] Publish
            - [ ] Serialize
            - [x] Deserialize
                - [x] State blocks
                - [ ] Other blocks
        - [ ] Bulk pull
        - [ ] Bulk pull account
        - [ ] Bulk pull blocks
        - [ ] Bulk push
        - [x] Telemetry Req
            - [x] Serialize
            - [x] Deserialize
        - [ ] Telemetry Ack
            - [ ] Serialize
            - [x] Deserialize
                - [x] Most fields
                - [ ] Timestamp
                - [ ] Active difficulty
            - [x] Validate signature
        - [ ] Frontier Req
            - [ ] Serialize
            - [x] Deserialize
    - [ ] Storage
        - [x] Basic KV store to file
        - [x] Basic cookie/peer storage
        - [ ] Peers
        - [ ] Blocks
        - [ ] ...
    - [ ] RPC
- [ ] Rust
    - [ ] Ask around for a code review
    - [ ] Use either `zerocopy` or make all core types zero-copy with storing `[u8]` and methods as
      accessors. `zerocopy`
      did work for most things when I tried but had problems with enums. Might revisit.
    - [ ] Use `thiserror` instead of `anyhow` in certain places.
    - [ ] Github actions CI (including `cargo clippy`)
- [ ] Future things
    - [ ] Fast bootstrapping related to the user's wallet
    - [ ] Performance
        - [ ] Automated comparison
    - [ ] Proof of work
        - [ ] Server
        - [ ] GPU
    - [ ] WASM

## Credits and references

* Thanks to the hard work from the Nano Foundation.
* https://github.com/nanocurrency/nano-node
    * The actual Nano implementation as a source of truth.
* https://forum.nano.org/, https://old.reddit.com/r/nanocurrency/, Nano Discord: https://chat.nano.org/
    * A very friendly community helping out others and myself.
* https://docs.nano.org/
    * General useful information.
* https://nanoo.tools/
    * Helped me understand technical details on state blocks and hashing, and also with validating conversions between
      things.
* https://github.com/nanocurrency/protocol/blob/master/reference
    * Node protocol specification.
* https://iancoleman.io/bip39/
    * Helped me test out my BIP 39/BIP 44 implementations.

## Other implementations

* nano-rs (Rust) https://github.com/termhn/nano-rs
* Railroad (Rust) https://github.com/PlasmaPower/railroad
* nano-python (Python) https://github.com/orhanhenrik/nano-python-node
* gonano (Go) https://github.com/alexbakker/gonano
* Go Nano (Go)  https://github.com/frankh/nano
* Node.js Nano Node (JavaScript) https://github.com/numtel/node-nano-node
* nanocurrency-node (TypeScript) https://github.com/pRizz/nanocurrency-node
* Prailude (Lua, C) https://github.com/slact/prailude
* RaiSharp (C#) https://github.com/vardthomas/Aggrex.RaiSharp

## License

Licensed under either of these at your option:

* Apache License, Version 2.0 ([LICENSE-APACHE](LICENSE-APACHE) or http://www.apache.org/licenses/LICENSE-2.0)
* MIT license ([LICENSE-MIT](LICENSE-MIT) or http://opensource.org/licenses/MIT)

## Contribution

Unless you explicitly state otherwise, any contribution intentionally submitted for inclusion in the work by you, as
defined in the Apache-2.0 license, shall be dual licensed as above, without any additional terms or conditions.