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README.md

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+# lego-monitoring
+
+Simple system monitoring service. Sends alerts in Telegram. Currently supports monitoring:
+* CPU/RAM/network usage
+* temperature readings
+* [vulnix](https://github.com/nix-community/vulnix) readings (NixOS only)
+
+## Setup
+
+### NixOS
+
+Only flake-based setups are supported.
+
+Include the module in your `flake.nix`:
+
+```nix
+{
+  inputs = {
+    # ... your other inputs ...
+    lego-monitoring = {
+      url = "git+https://gitlab.altau.su/lego/lego-monitoring.git";
+      inputs.nixpkgs.follows = "nixpkgs";
+    };
+  };
+
+  outputs = {
+    nixpkgs,
+    lego-monitoring,
+    ...
+  }: {
+    # change `yourhostname` to your actual hostname
+    nixosConfigurations.yourhostname = nixpkgs.lib.nixosSystem {
+      # change to your system:
+      system = "x86_64-linux";
+      modules = [
+        lego-monitoring.nixosModules.default
+        ./configuration.nix
+        # ... your other modules ...
+      ];
+    };
+  };
+}
+```
+
+See [docs/nixos-options.md](docs/nixos-options.md) for available configuration options.
+
+### Non-NixOS
+
+Requires [uv](https://github.com/astral-sh/uv), systemd.
+
+```bash
+cd /opt
+git clone https://gitlab.altau.su/lego/lego-monitoring.git
+cd lego-monitoring
+uv sync
+cp config.example.json config.json
+```
+
+Edit `config.json` to suit your usage scenario. The default configuration only sends alerts on service's start and stop.
+You may refer to the NixOS option documentation, as its options are the same, except JSON uses snake_case instead of lowerCamelCase.
+
+Then enable and start the service:
+
+```bash
+ln -s /opt/lego-monitoring/lego-monitoring.service /etc/systemd/system/lego-monitoring.service
+systemctl enable --now lego-monitoring
+```