This plugin exposes some key metrics from c-lightning in the prometheus format so it can be scraped, plotted and alerts can be created on it. The plugin adds the following command line arguments:

• prometheus-listen: the IP address and port to bind the HTTP server to (default: 127.0.0.1:9750)

Exposed variables include:

• node: ID, version, ...
• peers: whether they are connected, and how many channels are currently open
• channels: fund allocations, spendable funds, and how many unresolved HTLCs are currently attached to the channel
• funds: satoshis in on-chain outputs, satoshis allocated to channels and total sum (may be inaccurate during channel resolution).

You need uv to run this plugin like a binary. After uv is installed you can simply run

lightning-cli plugin start /path/to/prometheus.py

If you use systemd to start CLN, you must have uv in the PATH that systemd uses, which is likely different than the PATH from your shell. Most uv installation methods install uv into your user's home directory (~/.local/bin or ~/.cargo/bin), which systemd cannot access.

You can either:

Option 1: Install uv system-wide (recommended):

curl -LsSf https://astral.sh/uv/install.sh | sudo env UV_INSTALL_DIR="/usr/local/bin" sh

Option 2: Copy your existing user installation:

sudo cp "$(command -v uv)" /usr/local/bin/uv

Option 3: Configure your systemd service to use a custom PATH (see systemd documentation).

To verify uv is accessible to systemd:

sudo systemd-run --user --wait command -v uv

This should output /usr/local/bin/uv.

For general plugin installation instructions see the repos main README.md