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README.md

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+# NixOS Configuration
+
+Personal NixOS configuration for my machines, using Nix Flakes for reproducible and shareable setups.
+
+## Repository Structure
+
+- **flake.nix**: Main entry point for the Nix Flake, defining NixOS and home-manager configurations
+- **hosts/**: Host-specific NixOS configurations
+- **modules/**: Custom NixOS modules reusable across different hosts
+- **programs/**: System-level programs shared across hosts
+- **secrets/**: Encrypted secrets managed with sops-nix
+- **system/**: Common system-level configurations shared across hosts
+- **users/phundrak/**: Home-manager configuration for my user
+- **users/modules/**: Custom user modules reusable across configurations
+
+## Usage
+
+### System Management
+
+Update flake dependencies:
+```bash
+nix flake update
+```
+
+Build and switch to a new system configuration:
+```bash
+sudo nixos-rebuild switch --flake .#<hostname>
+```
+
+Using the Nix Helper (nh) tool:
+```bash
+# Build and activate a new configuration, making it the boot default
+nh os switch
+
+# Build a new configuration and make it the boot default
+nh os boot
+
+# Build and activate a new configuration (without making it the boot default)
+nh os test
+
+# Just build a new configuration
+nh os build
+```
+
+### Home Configuration
+
+Update and switch to a new home configuration:
+```bash
+nh home switch
+```
+
+Format Nix files (using Alejandra):
+```bash
+nix fmt
+```
+
+## Development
+
+For development, a devShell is provided with linting tools and git hooks:
+
+```bash
+nix develop
+```
+
+This will set up an environment with:
+- alejandra (formatting)
+- commitizen (commit messages)
+- deadnix (dead code detection)
+- statix (linting)
+- Other useful git hooks
+
+## Contributing
+
+Feel free to fork this repository and make your own changes. If you have any improvements or suggestions, please open an issue or submit a pull request.