LNURL for phoenixd ⚡️

👾 Also available on the P2P Git forge, Radicle at rad:z4G6sJdYgCqKswKnrBbYgn9QaHBqh

🚧 NOTE This is new software, loss of funds and other mishaps are likely 🚧

A simple wrapper for ACINQ/phoenixd that supports basic LNURL so you can self-host your lightning address with near-minimum effort 💯.

Supports one user with a human-readable LNURL like lightning:[email protected], as well as LNURL LUD-06 (the long Bech encoded lightning:LNURL1blahblah kind) and a snazzy tip webpage at /lnurl:

The idea is that you can run your own phoenixd instance and use it to receive Lightning tips, Zaps on Nostr and more-generally small usually un-requested payments. This is intended for a single person to use, because you like self-hosting and owning your own stuff.

If you're looking for something more complex, like an eCommerce Lightning solution, this is almost certainly going to be too simple for you; check out LNBits or BTCPay Server and other things like those. Note that LNBits will support phoenixd soon™️.

Compatibility

Developed against phoenixd version 0.1.4-04bd430 (and 0.1.3-d805f81); also note that phoenixd is also new software and future releases may break things.

Currently tested on MacOS and Linux; YMMV on other UNIXes, and on Windows.

Supported LNURL LUDs:

• LUD-01: Base LNURL encoding and decoding
• LUD-06: payRequest base spec.
• LUD-16: Paying to static internet identifiers (email-like addresses).

Docker Setup

A docker container with the latest release is available from ghcr.io/angusp/phoenixd-lnurl:latest.

Each of the settings in phoenixd-lnurl.env can be set using environment variables passed to the container, which is probably the easiest way to set this up.

As you'll also need to run phoenixd and some sort of webserver, so using Docker compose is likely easiest way to get all of the required pieces running: ./examples/docker-compose.yml:

docker-compose -f examples/docker-compose.yml up

To run just the phoenixd-lnurl image instead:

# Pull the image:
docker pull ghcr.io/angusp/phoenixd-lnurl:latest
docker tag ghcr.io/angusp/phoenixd-lnurl:latest phoenixd-lnurl:latest
# or build the image from a locally checked-out repo:
docker build . -t phoenixd-lnurl:latest

docker run -p 8000:8000 \
    # Pass config as environment variables: (See phoenixd-lnurl.env.example for the list)
    --env USERNAME=satoshi \
    --env PHOENIXD_URL="http://_:[email protected]:9740" \
    --env LNURL_HOSTNAME=example.com \
    # Or pass in a .env file:
    --env-file phoenixd-lnurl.env \
    -it phoenixd-lnurl:latest

• localhost:8000/lnurl Tip webpage as in the screenshot above
• localhost:8000/.well-known/lnurlp/<USERNAME> LNURL payRequest endpoint (LUD-16) for <USERNAME>@<LNURL_HOSTNAME>
• localhost:8000/lnurlp/<USERNAME> LNURL payRequest endpoint (LUD-06)
• localhost:8000/lnurlp/<USERNAME>/callback?amount=<AMOUNT_MSAT> LNURL payRequest callback (LUD-06 and LUD-16)
• Note localhost:8000/ and any other path will give you an ERROR -- that's supposed to happen, as it isn't a LNURL that pheonixd-lnurl understands 😉

Non-Docker Setup

If you haven't got it already, install phoenixd so you have phoenixd and phoenix-cli in your path.

See .tool-versions for the currently used version of Python. We're also using pip-tools to manage dependencies.

# Strongly recommend you create a python environment first:
python -m venv env
. env/bin/activate

# manually install pip-tools:
pip install pip-tools

# then sync the dependencies:
pip-sync

Using this example ~/.phoenix/phoenix.conf for demonstration purposes:

chain=testnet
http-password=hunter2
http-bind-port=9740
auto-liquidity=2m

For production use, you can just install and run phoenixd for the first time; it will create ~/.phoenix with sane defaults and an auto-generated http password.

You'll then need to configure phoenixd-lnurl itself. Copy phoenixd-lnurl.env.example to phoenixd-lnurl.env and edit it with the values you want; info on each option is given in the template.

Importantly:

1. PHOENIXD_URL needs to set so that this app can talk to your phoenixd.
   • Note that the http-password from phoenixd's config has to be in this URL
2. LNURL_HOSTNAME must be the public domain you're serving from. You need to have HTTPS set up for LNURL to work.

Now you're ready to run:

# start the phoenixd-lnurl server:
./run.sh

• localhost:8000/lnurl Tip webpage as in the screenshot above
• localhost:8000/.well-known/lnurlp/<USERNAME> LNURL payRequest endpoint (LUD-16) for <USERNAME>@<LNURL_HOSTNAME>
• localhost:8000/lnurlp/<USERNAME> LNURL payRequest endpoint (LUD-06)
• localhost:8000/lnurlp/<USERNAME>/callback?amount=<AMOUNT_MSAT> LNURL payRequest callback (LUD-06 and LUD-16)
• Note localhost:8000/ and any other path will give you an ERROR -- that's supposed to happen, as it isn't a LNURL that pheonixd-lnurl understands 😉

To deploy, you probably want something to manage phoenixd-lnurl as a service, rather than running it directly. Some example config is provided to help with this:

Example configuration:

• Docker compose: ./examples/docker-compose.yml
• Nginx: ./examples/nginx.conf
• Systemd: ./examples/phoenixd-lnurl.service

(Note: You may also hit a selinux issue if using nginx, try setsebool -P httpd_can_network_connect true)

Developing

There's a set of additional dev requirements you need to install for tests to work and stuff:

Life will be easier if you also have just installed, but you can get by without it.

just install
# Or, manually:
# $ pip-sync requirements-dev.txt

# Run just just to see other options
just

# API docs (paths for phoenixd-lnurl with try-it-out buttons):
just docs

If you are stubborn, you can also forego installing pip-tools and use a regular pip install -r requirements-dev.txt, but changes to requirements must be made using the pip-tools tooling.

Using a tool like ngrok to proxy your local server (and optionally phoenixd) to the internet is handy, as LNURL requires https for clearnet.

Getting a decent testnet Lightning wallet with all the bells and whistles is also a bit of a pain. I found Zeus worked well using the Embedded LND node on testnet without much fuss -- caveat being that you can't also have a mainnet embedded LND configured. Running a second phoenixd would also work, but it doesn't support LNURL so you'd have to copy-paste invoices and manually call phoenixd-lnurl.

Once you have that, you'll have to hunt for a testnet faucet to get some testnet sats.

When ready:

# Make sure you've already got `phoenixd` running!
just serve

Roadmap to v1.0

• Just receive LNURL LUD-16 payments (zaps)
• Simple "zap me" QR code and copyable lightning:LNURL1... link webpage LUD-16
• Provide sample Docker image
• Provide sample docker-compose config (credit @sethforprivacy)
• Provide sample Nginx config
• Provide sample Systemd service definition
• Basic CI (check normal install, dev install)
• Provide sample Traefik config (in the docker-compose example) (credit @sethforprivacy)
• Support .onion hosting (HTTPS is assumed in a few places), needed for self-hosting on things like Umbrel
• Support LUD-18: Payer identity in payRequest protocol
• Support configurable URL prefix for the app for people that might have collisions or don't want to host at / (or do this in nginx conf)
• Support actual Nostr Zaps NIP-57: Lightning Zaps
• Support NIP-47: Nostr Wallet Connect

Later Roadmap

• Notify when payments are received (Nostr DM?)
• Support some kind of withdrawal mechanism (via Nostr DM?) instead of needing manual phoenix-cli use to get money out
• Also optionally be a Nostr NIP-05 server
• Support multiple usernames
• (maybe-scope-creep) auto-zap content you interact with/like on Nostr if funds are available

Tips 😘

lnurlp:[email protected] (yes, I am dogfooding) or tip page

License ⚖️

This work is dual-licensed under Apache 2.0 and BSD-2-Clause. You can choose between one of them if you use this work.

SPDX-License-Identifier: Apache-2.0 OR BSD-2-Clause