Merge remote-tracking branch 'origin/master' into staging-next

To get more information about how to review specific parts of Nixpkgs, refer to the documents linked to in the [overview section][overview].

If a pull request contains documentation changes that might require feedback from the documentation team, ping @NixOS/documentation-team on the pull request.

If you consider having enough knowledge and experience in a topic and would like to be a long-term reviewer for related submissions, please contact the current reviewers for that topic. They will give you information about the reviewing process. The main reviewers for a topic can be hard to find as there is no list, but checking past pull requests to see who reviewed or git-blaming the code to see who committed to that topic can give some hints.

Container system, boot system and library changes are some examples of the pull requests fitting this category.

- If you have commits `pkg-name: oh, forgot to insert whitespace`: squash commits in this case. Use `git rebase -i`.

- Format the commit messages in the following way:

  ```

  (pkg-name | nixos/<module>): (from -> to | init at version | refactor | etc)

  (Motivation for change. Link to release notes. Additional information.)

  ```

  For consistency, there should not be a period at the end of the commit message's summary line (the first line of the commit message).

- For consistency, there should not be a period at the end of the commit message's summary line (the first line of the commit message).

  Examples:

  * nginx: init at 2.0.1

  * firefox: 54.0.1 -> 55.0

    https://www.mozilla.org/en-US/firefox/55.0/releasenotes/

  * nixos/hydra: add bazBaz option

    Dual baz behavior is needed to do foo.

  * nixos/nginx: refactor config generation

    The old config generation system used impure shell scripts and could break in specific circumstances (see #1234).

  When adding yourself as maintainer, in the same pull request, make a separate

- When adding yourself as maintainer in the same pull request, make a separate

  commit with the message `maintainers: add <handle>`.

  Add the commit before those making changes to the package or module.

  See [Nixpkgs Maintainers](./maintainers/README.md) for details.

- Make sure you read about any commit conventions specific to the area you're touching. See:

  - [Commit conventions](./pkgs/README.md#commit-conventions) for changes to `pkgs`.

  - [Commit conventions](./lib/README.md#commit-conventions) for changes to `lib`.

  - [Commit conventions](./nixos/README.md#commit-conventions) for changes to `nixos`.

  - [Commit conventions](./doc/README.md#commit-conventions) for changes to `doc`, the Nixpkgs manual.

### Writing good commit messages

In addition to writing properly formatted commit messages, it's important to include relevant information so other developers can later understand *why* a change was made. While this information usually can be found by digging code, mailing list/Discourse archives, pull request discussions or upstream changes, it may require a lot of work.

watermelon

:   green fruit with red flesh

```

## Commit conventions

- Make sure you read about the [commit conventions](../CONTRIBUTING.md#commit-conventions) common to Nixpkgs as a whole.

- If creating a commit purely for documentation changes, format the commit message in the following way:

  ```

  doc: (documentation summary)

  (Motivation for change, relevant links, additional information.)

  ```

  Examples:

  * doc: update the kernel config documentation to use `nix-shell`

  * doc: add information about `nix-update-script`

    Closes #216321.

- If the commit contains more than just documentation changes, follow the commit message format relevant for the rest of the changes.

  To obtain the actual hash, set `vendorHash = lib.fakeHash;` and run the build ([more details here](#sec-source-hashes)).

- `proxyVendor`: Fetches (go mod download) and proxies the vendor directory. This is useful if your code depends on c code and go mod tidy does not include the needed sources to build or if any dependency has case-insensitive conflicts which will produce platform-dependent `vendorHash` checksums.

- `modPostBuild`: Shell commands to run after the build of the goModules executes `go mod vendor`, and before calculating fixed output derivation's `vendorHash` (or `vendorSha256`). Note that if you change this attribute, you need to update `vendorHash` (or `vendorSha256`) attribute.

- `modPostBuild`: Shell commands to run after the build of the goModules executes `go mod vendor`, and before calculating fixed output derivation's `vendorHash`. Note that if you change this attribute, you need to update `vendorHash` attribute.

```nix

pet = buildGoModule rec {

# Run the lib.fileset tests

fileset/tests.sh

```

## Commit conventions

- Make sure you read about the [commit conventions](../CONTRIBUTING.md#commit-conventions) common to Nixpkgs as a whole.

- Format the commit messages in the following way:

  ```

  lib.(section): (init | add additional argument | refactor | etc)

  (Motivation for change. Additional information.)

  ```

  Examples:

  * lib.getExe': check arguments

  * lib.fileset: Add an additional argument in the design docs

    Closes #264537

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`.

## Commit conventions

- Make sure you read about the [commit conventions](../CONTRIBUTING.md#commit-conventions) common to Nixpkgs as a whole.

- Format the commit messages in the following way:

  ```

  nixos/(module): (init module | add setting | refactor | etc)

  (Motivation for change. Link to release notes. Additional information.)

  ```

  Examples:

  * nixos/hydra: add bazBaz option

    Dual baz behavior is needed to do foo.

  * nixos/nginx: refactor config generation

    The old config generation system used impure shell scripts and could break in specific circumstances (see #1234).

## 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.