Starting work on fan control with opencode

AGENTS.md

@@ -0,0 +1,26 @@
+# AGENTS.md
+
+This document outlines the development conventions for this NixOS-based infrastructure repository.
+
+## Build & Deployment
+
+- **Build/Deploy:** Use `nixos-rebuild switch --flake .#<hostname>` to build and deploy the configuration for a specific host.
+- **Development Shell:** Activate the development environment with `nix develop`.
+
+## Linting & Formatting
+
+- **Formatting:** This project uses `nixpkgs-fmt` for automatic formatting. Ensure it is run before committing changes.
+  - `nixpkgs-fmt .`
+- **Linting:** No specific linter is configured, but adhere to standard Nix language conventions.
+
+## Testing
+
+- No automated testing suite is configured. Manually verify changes by deploying to a non-critical host.
+
+## Code Style & Conventions
+
+- **Imports:** Keep module imports clean and organized at the top of files.
+- **Naming:** Follow Nix community conventions for variable and function names (e.g., `camelCase` for variables, `kebab-case` for package names).
+- **Secrets:** Secrets are managed with `agenix`. Edit encrypted files with `agenix -e <file>`.
+- **Modularity:** Structure configurations into logical, reusable modules under `modules/`. New modules should be registered in `modules/nixos/default.nix` to be available to all hosts.
+- **Error Handling:** Ensure Nix expressions are robust and handle potential evaluation errors gracefully.

modules/nixos/default.nix

@@ -5,5 +5,6 @@
       # ./programs
       ./services
       ./filesystem
+      ./services/systemd
     ];
 }

modules/nixos/services/systemd/fancontrol.nix

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+{ config, lib, pkgs, ... }:
+
+with lib;
+
+let
+  cfg = config.services.systemd-fancon;
+in
+{
+  options.services.systemd-fancon = {
+    enable = mkEnableOption "systemd-fancon service for fan control";
+    config = mkOption {
+      type = types.lines;
+      default = "";
+      description = "Configuration for systemd-fancon.";
+    };
+  };
+
+  config = mkIf cfg.enable {
+    environment.systemPackages = with pkgs; [
+      systemd-fancon
+      lm_sensors
+    ];
+
+    boot.kernelModules = [ "amdgpu" ];
+
+    systemd.services.systemd-fancon = {
+      description = "systemd-fancon service";
+      wantedBy = [ "multi-user.target" ];
+      after = [ "network-online.target" ];
+      serviceConfig = {
+        ExecStart = "${pkgs.systemd-fancon}/bin/systemd-fancon -c ${cfg.configFile}";
+        Restart = "on-failure";
+      };
+      configFile = pkgs.writeText "systemd-fancon.conf" cfg.config;
+    };
+  };
+}