nix-bitcoin/README.md

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nix-bitcoin

Nix packages and nixos modules for easily installing Bitcoin nodes and higher layer protocols with an emphasis on security. This is a work in progress - don't expect it to be bug free or secure.

The default configuration sets up a Bitcoin Core node and c-lightning. The user can enable spark-wallet in configuration.nix to make c-lightning accessible with a smartphone using spark-wallet. A simple webpage shows the lightning nodeid and links to nanopos letting the user receive donations. It also includes liquid-daemon. Outbound peer-to-peer traffic is forced through Tor, and listening services are bound to onion addresses.

A demo installation is running at http://6tr4dg3f2oa7slotdjp4syvnzzcry2lqqlcvqkfxdavxo6jsuxwqpxad.onion. The following screen cast shows a fresh deployment of a nix-bitcoin node.

The goal is to make it easy to deploy a reasonably secure Bitcoin node with a usable wallet. It should allow managing bitcoin (the currency) effectively and providing public infrastructure. It should be a reproducible and extensible platform for applications building on Bitcoin.

Available modules

By default the configuration.nix provides:

  • bitcoind (pruned) with outbound connections through Tor and inbound connections through a hidden service. By default loaded with banlist of spy nodes.
  • clightning with outbound connections through Tor, not listening
  • includes "nodeinfo" script which prints basic info about the node
  • adds non-root user "operator" which has access to bitcoin-cli and lightning-cli

In configuration.nix the user can enable:

  • a clightning hidden service
  • liquid-daemon
  • lightning charge
  • nanopos
  • an index page using nginx to display node information and link to nanopos
  • spark-wallet
  • electrs
  • recurring-donations, a module to repeatedly send lightning payments to recipients specified in the configuration.

The data directories of the services can be found in /var/lib on the deployed machines.

Installation

The easiest way is to run nix-shell (on a Linux machine) in the nix-bitcoin directory and then create a NixOps deployment with the provided network.nix in the network directory. Fix the FIXMEs in configuration.nix and deploy with nixops in nix-shell. See install.md for a detailed tutorial.

Security

  • Nix package manager, NixOS and packages can be built from source to reduce reliance on binary caches.
  • Builds happen in a sandboxed environment.
  • Packages dependencies are pinned. Most packages are built from the nixos stable channel, with a few exceptions that are built from the nixpkgs unstable channel.
  • nix-bitcoin merge commits are signed.
  • nix-bitcoin is built with a hardened kernel by default.
  • Services operate with least privileges. They each have their own user and are restricted further with systemd options.
  • There's a non-root user operator to interact with the various services.

Note that nix-bitcoin is still experimental. Also, by design if the machine you're deploying from is insecure, there is nothing nix-bitcoin can do to protect itself.

Hardware requirements

  • Disk space: 300 GB (235GB for Bitcoin blockchain + some room)
    • Bitcoin Core pruning is not supported at the moment because it's not supported by c-lightning. It's possible to use pruning but you need to know what you're doing.
  • RAM: 2GB of memory

Tested hardware includes pcengine's apu2c4

Usage

For usage instructions, such as how to connect to spark-wallet, electrs and the ssh Tor Hidden Service, see usage.md.

Troubleshooting

If you are having problems with nix-bitcoin check the FAQ or submit an issue. We are always happy to help.

Docs