# NixOS NixOS is a Linux distribution based on the purely functional package management system Nix. More information can be found at https://nixos.org/nixos and in the manual in doc/manual. ## Testing changes You can add new module to your NixOS configuration file (usually it’s `/etc/nixos/configuration.nix`). And do `sudo nixos-rebuild test -I nixpkgs=<path to your local nixpkgs folder> --fast`. ## Reviewing contributions When changing the bootloader installation process, extra care must be taken. Grub installations cannot be rolled back, hence changes may break people’s installations forever. For any non-trivial change to the bootloader please file a PR asking for review, especially from \@edolstra. ### Module updates Module updates are submissions changing modules in some ways. These often contains changes to the options or introduce new options. Reviewing process: - Ensure that the module maintainers are notified. - [CODEOWNERS](https://help.github.com/articles/about-codeowners/) will make GitHub notify users based on the submitted changes, but it can happen that it misses some of the package maintainers. - Ensure that the module tests, if any, are succeeding. - Ensure that the introduced options are correct. - Type should be appropriate (string related types differs in their merging capabilities, `loaOf` and `string` types are deprecated). - Description, default and example should be provided. - Ensure that option changes are backward compatible. - `mkRenamedOptionModuleWith` provides a way to make option changes backward compatible. - Ensure that removed options are declared with `mkRemovedOptionModule` - Ensure that changes that are not backward compatible are mentioned in release notes. - Ensure that documentations affected by the change is updated. Sample template for a module update review is provided below. ```markdown ##### Reviewed points - [ ] changes are backward compatible - [ ] removed options are declared with `mkRemovedOptionModule` - [ ] changes that are not backward compatible are documented in release notes - [ ] module tests succeed on ARCHITECTURE - [ ] options types are appropriate - [ ] options description is set - [ ] options example is provided - [ ] documentation affected by the changes is updated ##### Possible improvements ##### Comments ``` ### New modules New modules submissions introduce a new module to NixOS. Reviewing process: - Ensure that the module tests, if any, are succeeding. - Ensure that the introduced options are correct. - Type should be appropriate (string related types differs in their merging capabilities, `loaOf` and `string` types are deprecated). - Description, default and example should be provided. - Ensure that module `meta` field is present - Maintainers should be declared in `meta.maintainers`. - Module documentation should be declared with `meta.doc`. - Ensure that the module respect other modules functionality. - For example, enabling a module should not open firewall ports by default. Sample template for a new module review is provided below. ```markdown ##### Reviewed points - [ ] module path fits the guidelines - [ ] module tests succeed on ARCHITECTURE - [ ] options have appropriate types - [ ] options have default - [ ] options have example - [ ] options have descriptions - [ ] No unneeded package is added to environment.systemPackages - [ ] meta.maintainers is set - [ ] module documentation is declared in meta.doc ##### Possible improvements ##### Comments ```