Merge master into staging-next

$ nix-env --install --attr nix-prefetch-git  # Used by dhall-to-nixpkgs

$ dhall-to-nixpkgs github https://github.com/Gabriel439/dhall-semver.git

$ dhall-to-nixpkgs github https://github.com/Gabriella439/dhall-semver.git

{ buildDhallGitHubPackage, Prelude }:

  buildDhallGitHubPackage {

    name = "dhall-semver";

    githubBase = "github.com";

    owner = "Gabriel439";

    owner = "Gabriella439";

    repo = "dhall-semver";

    rev = "2d44ae605302ce5dc6c657a1216887fbb96392a4";

    fetchSubmodules = false;

: Whether to generate an index for interactive navigation of the HTML documentation.

Defaults to `true` if supported.

`doInstallIntermediates`

: Whether to install intermediate build products (files written to `dist/build`

by GHC during the build process). With `enableSeparateIntermediatesOutput`,

these files are instead installed to [a separate `intermediates`

output.][multiple-outputs] The output can then be passed into a future build of

the same package with the `previousIntermediates` argument to support

incremental builds. See [“Incremental builds”](#haskell-incremental-builds) for

more information. Defaults to `false`.

`enableLibraryProfiling`

: Whether to enable [profiling][profiling] for libraries contained in the

package. Enabled by default if supported.

: Whether to install documentation to a separate `doc` output.

Is automatically enabled if `doHaddock` is `true`.

`enableSeparateIntermediatesOutput`

: When `doInstallIntermediates` is true, whether to install intermediate build

products to a separate `intermediates` output. See [“Incremental

builds”](#haskell-incremental-builds) for more information. Defaults to

`false`.

`allowInconsistentDependencies`

: If enabled, allow multiple versions of the same Haskell package in the

dependency tree at configure time. Often in such a situation compilation would

when loading the library in the REPL, but requires extra build time and

disk space. Defaults to `false`.

`previousIntermediates`

: If non-null, intermediate build artifacts are copied from this input to

`dist/build` before performing compiling. See [“Incremental

builds”](#haskell-incremental-builds) for more information. Defaults to `null`.

`buildTarget`

: Name of the executable or library to build and install.

If unset, all available targets are built and installed.

    * `broken`

    * `hydraPlatforms`

### Incremental builds {#haskell-incremental-builds}

`haskellPackages.mkDerivation` supports incremental builds for GHC 9.4 and

newer with the `doInstallIntermediates`, `enableSeparateIntermediatesOutput`,

and `previousIntermediates` arguments.

The basic idea is to first perform a full build of the package in question,

save its intermediate build products for later, and then copy those build

products into the build directory of an incremental build performed later.

Then, GHC will use those build artifacts to avoid recompiling unchanged

modules.

For more detail on how to store and use incremental build products, see

[Gabriella Gonzalez’ blog post “Nixpkgs support for incremental Haskell

builds”.][incremental-builds] motivation behind this feature.

An incremental build for [the `turtle` package][turtle] can be performed like

so:

```nix

let

  pkgs = import <nixpkgs> {};

  inherit (pkgs) haskell;

  inherit (haskell.lib.compose) overrideCabal;

  # Incremental builds work with GHC >=9.4.

  turtle = haskell.packages.ghc944.turtle;

  # This will do a full build of `turtle`, while writing the intermediate build products

  # (compiled modules, etc.) to the `intermediates` output.

  turtle-full-build-with-incremental-output = overrideCabal (drv: {

    doInstallIntermediates = true;

    enableSeparateIntermediatesOutput = true;

  }) turtle;

  # This will do an incremental build of `turtle` by copying the previously

  # compiled modules and intermediate build products into the source tree

  # before running the build.

  #

  # GHC will then naturally pick up and reuse these products, making this build

  # complete much more quickly than the previous one.

  turtle-incremental-build = overrideCabal (drv: {

    previousIntermediates = turtle-full-build-with-incremental-output.intermediates;

  }) turtle;

in

  turtle-incremental-build

```

## Development environments {#haskell-development-environments}

In addition to building and installing Haskell software, nixpkgs can also

[haskell.nix]: https://input-output-hk.github.io/haskell.nix/index.html

[HLS user guide]: https://haskell-language-server.readthedocs.io/en/latest/configuration.html#configuring-your-editor

[hoogle]: https://wiki.haskell.org/Hoogle

[incremental-builds]: https://www.haskellforall.com/2022/12/nixpkgs-support-for-incremental-haskell.html

[jailbreak-cabal]: https://github.com/NixOS/jailbreak-cabal/

[multiple-outputs]: https://nixos.org/manual/nixpkgs/stable/#chap-multiple-output

[optparse-applicative-completions]: https://github.com/pcapriotti/optparse-applicative/blob/7726b63796aa5d0df82e926d467f039b78ca09e2/README.md#bash-zsh-and-fish-completions

[profiling-detail]: https://cabal.readthedocs.io/en/latest/cabal-project.html#cfg-field-profiling-detail

[profiling]: https://downloads.haskell.org/~ghc/latest/docs/html/users_guide/profiling.html

[search.nixos.org]: https://search.nixos.org

[turtle]: https://hackage.haskell.org/package/turtle

    githubId = 606000;

    name = "Gabriel Adomnicai";

  };

  Gabriel439 = {

    email = "Gabriel439@gmail.com";

    github = "Gabriella439";

    githubId = 1313787;

    name = "Gabriel Gonzalez";

  };

  GabrielDougherty = {

    email = "contact@gabrieldougherty.com";

    github = "GabrielDougherty";

    githubId = 10541219;

    name = "Gabriel Dougherty";

  };

  Gabriella439 = {

    email = "GenuineGabriella@gmail.com";

    github = "Gabriella439";

    githubId = 1313787;

    name = "Gabriella Gonzalez";

  };

  gador = {

    email = "florian.brandes@posteo.de";

    github = "gador";

    githubId = 26231126;

    name = "Nils ANDRÉ-CHANG";

  };

  nim65s = {

    email = "guilhem.saurel@laas.fr";

    matrix = "@gsaurel:laas.fr";

    github = "nim65s";

    githubId = 131929;

    name = "Guilhem Saurel";

    keys = [{

      fingerprint = "9B1A 7906 5D2F 2B80 6C8A  5A1C 7D2A CDAF 4653 CF28";

    }];

  };

  ninjatrappeur = {

    email = "felix@alternativebit.fr";

    matrix = "@ninjatrappeur:matrix.org";

  dhall = {

    members = [

      Gabriel439

      Gabriella439

      ehmry

    ];

    scope = "Maintain Dhall and related packages.";

    shortName = "Minimal Bootstrap";

  };

  mercury = {

    members = [

      _9999years

      Gabriella439

    ];

    scope = "Group registry for packages maintained by Mercury";

    shortName = "Mercury Employees";

  };

  mobile = {

    members = [

      samueldr

        environment.systemPackages = optional (cfg.package != null) cfg.package ++ cfg.extraPackages;

        # To make a river session available if a display manager like SDDM is enabled:

        programs.xwayland.enable = mkDefault true;

        services.xserver.displayManager.sessionPackages = optionals (cfg.package != null) [ cfg.package ];

      }

      (import ./wayland-session.nix { inherit lib pkgs; })

    ]);