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{{Cleanup}}

'''Nix Flakes''' (Флейки Nix) — это [[Experimental Nix features|экспериментальная функция]], впервые представленная в релизе [[Nix]] 2.4{{Cite manual|nix|development/experimental-features|number=13.8|title=Experimental Features|subsection=xp-feature-flakes|subtitle=flakes}}{{Cite manual|nix|release-notes/rl-2.4|number=14.27|title=Release 2.4 (2021-11-01)}}, которая направлена на решение ряда задач по улучшению экосистемы Nix: Флейки предоставляют единую структуру для Nix-проектов, позволяя фиксировать конкретные версии каждой зависимости, делиться этими зависимостями с помощью lock-файлов и в целом делать запись репродуцируемых Nix-выражений более удобной.

Флейк — это каталог, который содержит файл Nix с именем <code>flake.nix</code>, который следует очень конкретной структуре. Флейки вводят похожий на URL синтаксис{{Cite manual|nix|command-ref/new-cli/nix3-flake|number=8.5.17|title=nix flake|subsection=url-like-syntax|subtitle=URL-like syntax}} для указания удалённых ресурсов. Чтобы упростить синтаксис, флейки используют реестр символических идентификаторов{{Cite manual|nix|command-ref/new-cli/nix3-registry|number=8.5.62|title=nix registry}}, что позволяет напрямую ссылаться на ресурсы в следующей форме: <code>github:NixOS/nixpkgs</code>.

Флейки также поддерживают фиксацию ссылок и версий, которые затем могут быть запрошены и обновлены программно через inputs{{cite manual|nix|command-ref/new-cli/nix3-flake-lock|number=7.5.19|title=nix flake lock}}{{cite manual|nix|command-ref/new-cli/nix3-flake-info|number=7.5.17|title=nix flake info}}. Кроме того, экспериментальная утилита командной строки принимает flake-ссылки для выражений, которые собирают, выполняют и развёртывают пакеты{{Cite manual|nix|command-ref/new-cli/nix|number=8.5.1|title=nix}}.

== Структура flake-файла ==
В простейшем виде flake-файл содержит описание флейка, набор входных зависимостей (inputs) и выход (output). Вы можете сгенерировать шаблонный flake-файл в любой момент с помощью <code>nix flake init</code>. Это создаст в текущей директории файл <code>flake.nix</code>, содержащий примерно следующее:
{{File|3=<nowiki>{
  description = "A very basic flake";

  inputs = {
    nixpkgs.url = "github:nixos/nixpkgs?ref=nixos-unstable";
  };

  outputs = { self, nixpkgs }: {

    packages.x86_64-linux.hello = nixpkgs.legacyPackages.x86_64-linux.hello;

    packages.x86_64-linux.default = self.packages.x86_64-linux.hello;

  };
}</nowiki>|name=flake.nix|lang=nix}}
В примере выше вы можете видеть описание, вход (input), указанный как репозиторий GitHub с конкретной веткой (здесь <code>nixos/nixpkgs</code> на ветке <code>nixos-unstable</code>), и выход (output), который использует этот input. Output в этом примере просто определяет, что в флейке есть один пакет для архитектуры x86_64 под именем <code>hello</code>. Даже если output вашего флейка не использует его inputs (что на практике маловероятно), output всё равно должен быть Nix-функцией.
{{Note|Флейки требуют явного указания outputs для каждой архитектуры отдельно. Для дополнительной информации смотрите соответствующий раздел ниже.}}

<div class="mw-translate-fuzzy">
=== Конфигурация Nix ===
Можно переопределить глобальную конфигурацию Nix, заданную в файле <code>nix.conf</code>, чтобы оценить работу флейка. Это может быть полезно, например, для установки бинарных кэшей, специфичных для проекта, пока глобальная конфигурация останется нетронутой. Flake-файл может содержать атрибут <code>nixConfig</code> с любыми релевантными настройками. Например, чтобы включить бинарный кэш nix-community, можно добавить:
{{File|3=<nowiki>{
  ...
  nixConfig = {
    extra-substituters = [
      "https://nix-community.cachix.org"
    ];
    extra-trusted-public-keys = [
      "nix-community.cachix.org-1:...="
    ];
}</nowiki>|name=flake.nix|lang=nix}}{{Note|Если вы привыкли настраивать Nix через конфигурацию NixOS, эти опции находятся под <code>nix.settings</code>, а не под <code>nix</code>. Например, вы не сможете указать автоматическую оптимизацию хранилища через <code>nix.optimisation.enable</code>.}}
</div>

<div lang="en" dir="ltr" class="mw-content-ltr">
== Setup ==
</div>

<span id="Enabling_flakes_temporarily"></span>
<div class="mw-translate-fuzzy">
==== Временно включить поддержку Flakes ====
</div>

<div class="mw-translate-fuzzy">
При использовании любой команды <code>nix</code> добавьте следующие параметры командной строки:
</div>
<syntaxhighlight lang="shell">
 --experimental-features 'nix-command flakes'
</syntaxhighlight>
<div lang="en" dir="ltr" class="mw-content-ltr">
=== Enabling flakes permanently ===
</div>

<span id="NixOS"></span>
<div class="mw-translate-fuzzy">
====Включить flakes на постоянной основе в NixOS====
</div>

Добавьте следующее в [[Overview_of_the_NixOS_Linux_distribution#Declarative_Configuration system configuration |Конфигурацию NixOS]]:

<syntaxHighlight lang=nix>
  nix.settings.experimental-features = [ "nix-command" "flakes" ];
</syntaxHighlight>

<span id="Home_Manager"></span>
<div class="mw-translate-fuzzy">
===== В других Дистрибутивах, с Home-Manager =====
</div>

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Добавьте следующее в свою конфигурацию Home-Manager:
</div>

<syntaxhighlight lang="nix">
  nix.settings.experimental-features = [ "nix-command" "flakes" ];
</syntaxhighlight>

<span id="Nix_standalone"></span>
<div class="mw-translate-fuzzy">
=====Другие Дистрибутивы, без Home-Manager=====
</div>

{{Note | [https://github.com/DeterminateSystems/nix-installer Детерминированный Установщик Nix (Determinate Nix Installer)] включает Flakes по умолчанию.}}

Добавьте следующее в <code>~/.config/nix/nix.conf</code> или <code>/etc/nix/nix.conf</code>:

<syntaxHighlight lang=text>
experimental-features = nix-command flakes
</syntaxHighlight>
<span id="Usage"></span>
<div class="mw-translate-fuzzy">
=== Основное Использование Flake ===
</div>

<div class="mw-translate-fuzzy">
{{Warning | Так как содержимое файлов Flake скопировано в общедоступную папку хранилища Nix, не храните никаких незашифрованных секретов в файлах Flake. Вам следует использовать [[Comparison of secret managing schemes|схемы управления секретами]].}}
</div>

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Для флейков в репозиториях git, только файлы из рабочего дерева (Working tree) будут скопированы в хранилище
</div>

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Поэтому если вы используете git для ваших флейков, не забывайте применять <code>git add</code> ко всем файлам репозитория, после того как вы их создаёте
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=== The nix flakes command ===
{{Main|Nix (command)}}
</div>

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The {{ic|nix flake}} subcommand is described in {{Nix Manual|name=command reference page of the Nix manual|anchor=command-ref/new-cli/nix3-flake}}.
</div>

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This flake produces a single flake output <code>packages</code>. And within that, <code>x86_64-linux</code> is a system-specifc attribute set. And within that, two package [[derivations]] <code>default</code> and <code>hello</code>. You can find outputs with the {{Nix Manual|name=show command|anchor=command-ref/new-cli/nix3-flake-show}} of a flake as shown below:
</div>

<div lang="en" dir="ltr" class="mw-content-ltr">
<syntaxhighlight lang="console">
$ nix flake show
└───packages
    └───x86_64-linux
        ├───default: package 'hello-2.12.2'
        └───hello: package 'hello-2.12.2'
</syntaxhighlight>
</div>

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==== Development shells ====
</div>

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A <code>devShell</code> is a Nix-provided [[Development_environment_with_nix-shell#nix develop|development environment]] defined within a flake. It lets you declare a reproducible shell environment with the tools, libraries, and environment variables you need for the development of a specific project. This is flake equivalent to defining a <code>nix-shell</code>.
</div>

<div lang="en" dir="ltr" class="mw-content-ltr">
<syntaxhighlight lang="nix">
{
  description = "Example flake with a devShell";
</div>

  <div lang="en" dir="ltr" class="mw-content-ltr">
inputs.nixpkgs.url = "github:nixos/nixpkgs?ref=nixos-unstable";
</div>

  <div lang="en" dir="ltr" class="mw-content-ltr">
outputs = { self, nixpkgs}:
    let
      system = "x86_64-linux";
      pkgs = import nixpkgs { inherit system; };
    in {
      devShells.x86_64-linux.default = pkgs.mkShell {
        buildInputs = with pkgs; [
          hello
        ];
        shellHook = ''
          echo "Welcome to the devShell!"
        '';
      };
    };
}
</syntaxhighlight>
</div>

<div lang="en" dir="ltr" class="mw-content-ltr">
To enter the development shell environment:
</div>

<div lang="en" dir="ltr" class="mw-content-ltr">
<syntaxhighlight lang="console">
$ nix develop
</syntaxhighlight>
</div>

<div lang="en" dir="ltr" class="mw-content-ltr">
{{note|You don’t need to define a devShell to enter a development shell using nix develop.
If no devShell is defined, nix develop will drop you into an environment containing the default build dependencies of the flake (if any).}}
</div>

<div lang="en" dir="ltr" class="mw-content-ltr">
==== Build specific attributes in a flake repository ====
</div>

<div lang="en" dir="ltr" class="mw-content-ltr">
Running <code>nix build</code> will look in the <code>legacyPackages</code> and <code>packages</code> output attributes for the corresponding [[derivation]] and then your system architecture and build the default output. If you want to specify a build attribute in a flake repository, you can run <code>nix build .#<attr></code>. In the example above, if you wanted to build the <code>packages.x86_64-linux.hello</code> attribute, run:
</div>

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<syntaxHighlight lang=console>
$ nix build .#hello
</syntaxHighlight>
</div>

<div lang="en" dir="ltr" class="mw-content-ltr">
Likewise, you can specify an attribute with the run command: <code>nix run .#hello</code> and the develop command: <code>nix develop .#hello</code>.
</div>

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== Flake schema ==
</div>

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The flake.nix file is a Nix file but that has special restrictions (more on that later).
</div>

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It has 4 top-level attributes:
</div>

* <code>description</code> это строка описывающая flake.

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* <code>inputs</code> is an attribute set of all the dependencies of the flake. The schema is described below.
</div>

<div lang="en" dir="ltr" class="mw-content-ltr">
* <code>outputs</code> is a function of one argument that takes an attribute set of all the realized inputs, and outputs another attribute set whose schema is described below.
</div>

<div lang="en" dir="ltr" class="mw-content-ltr">
* <code>nixConfig</code> is an attribute set of values which reflect the [https://nixos.org/manual/nix/stable/command-ref/conf-file.html values given to nix.conf]. This can extend the normal behavior of a user's nix experience by adding flake-specific configuration, such as a [[Binary Cache|binary cache]].
</div>

<span id="Input_schema"></span>
=== Входная схема ===

<div lang="en" dir="ltr" class="mw-content-ltr">
[https://nixos.org/manual/nix/stable/command-ref/new-cli/nix3-flake.html#flake-inputs The nix flake inputs manual].
</div>

<div lang="en" dir="ltr" class="mw-content-ltr">
[https://nixos.org/manual/nix/stable/command-ref/new-cli/nix3-flake.html#flake-references The nix flake references manual].
</div>

<div lang="en" dir="ltr" class="mw-content-ltr">
The inputs attribute defines the dependencies of the flake. For example, nixpkgs has to be defined as a dependency for a system flake in order for the system to build properly.
</div>

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[[Nixpkgs]] can be defined using the following code:
</div>

<code>inputs.nixpkgs.url = "github:NixOS/nixpkgs/<branch name>";</code>

Nixpkgs can alternatively also point to an url cached by the NixOS organization:

<code>inputs.nixpkgs.url = "<nowiki>https://nixos.org/channels/nixpkgs-unstable/nixexprs.tar.xz</nowiki>";</code>

In this example the input would point to the `nixpkgs-unstable` channel.


<div lang="en" dir="ltr" class="mw-content-ltr">
For any repository with its own flake.nix file, the website must also be defined. Nix knows where the nixpkgs repository is, so stating that it's on GitHub is unnecessary.
</div>

<div lang="en" dir="ltr" class="mw-content-ltr">
For example, adding [[Hyprland]] as an input would look something like this:
</div>

<code>inputs.hyprland.url = "github:hyprwm/Hyprland";</code>

<div lang="en" dir="ltr" class="mw-content-ltr">
If you want to make Hyprland follow the nixpkgs input to avoid having multiple versions of nixpkgs, this can be done using the following code:
</div>

<code>inputs.hyprland.inputs.nixpkgs.follows = "nixpkgs";</code>

<div lang="en" dir="ltr" class="mw-content-ltr">
Using curly brackets (<code>{}</code>), we can shorten all of this and put it in a table. The code will look something like this:
</div>

<syntaxhighlight lang="nix">
inputs = {
  nixpkgs.url = "github:NixOS/nixpkgs/<branch name>";
  hyprland = {
    url = "github:hyprwm/Hyprland";
    inputs.nixpkgs.follows = "nixpkgs";
  };
};
</syntaxhighlight>

<div lang="en" dir="ltr" class="mw-content-ltr">
By default, Git submodules in package <code>src</code>'s won't get copied to the nix store, this may cause the build to fail. Flakes in Git repositories can declare that they need Git submodules to be enabled. Since Nix version [https://discourse.nixos.org/t/nix-2-27-0-released/62003 2.27], you can enable submodules by:
</div>

<div lang="en" dir="ltr" class="mw-content-ltr">
<syntaxhighlight lang="nix">
  inputs.self.submodules = true;
</syntaxhighlight>
</div>

<div lang="en" dir="ltr" class="mw-content-ltr">
=== Output schema ===
</div>

<div lang="en" dir="ltr" class="mw-content-ltr">
This is described in the nix package manager [https://github.com/NixOS/nix/blob/master/src/nix/flake-check.md src/nix/flake-check.md].
</div>

<div lang="en" dir="ltr" class="mw-content-ltr">
Once the inputs are resolved, they're passed to the function `outputs` along with with `self`, which is the directory of this flake in the store. `outputs` returns the outputs of the flake, according to the following schema.
</div>

В которой:

<div lang="en" dir="ltr" class="mw-content-ltr">
* <code><system></code> is something like "x86_64-linux", "aarch64-linux", "i686-linux", "x86_64-darwin"
</div>

<div lang="en" dir="ltr" class="mw-content-ltr">
* <code><name></code> is an attribute name like "hello".
</div>

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* <code><flake></code> is a flake name like "nixpkgs".
</div>

<div lang="en" dir="ltr" class="mw-content-ltr">
* <code><store-path></code> is a <code>/nix/store..</code> path
</div>

<syntaxhighlight lang="nix">
{ self, ... }@inputs:
{
  # Executed by `nix flake check`
  checks."<system>"."<name>" = derivation;
  # Executed by `nix build .#<name>`
  packages."<system>"."<name>" = derivation;
  # Executed by `nix build .`
  packages."<system>".default = derivation;
  # Executed by `nix run .#<name>`
  apps."<system>"."<name>" = {
    type = "app";
    program = "<store-path>";
    meta = {description = "..."; inherit otherMetaAttrs; };
  };
  # Executed by `nix run . -- <args?>`
  apps."<system>".default = { type = "app"; program = "..."; meta = {description = "..."; inherit otherMetaAttrs; }; };

  # Formatter (alejandra, nixfmt, treefmt-nix or nixpkgs-fmt)
  formatter."<system>" = derivation;
  # Used for nixpkgs packages, also accessible via `nix build .#<name>`
  legacyPackages."<system>"."<name>" = derivation;
  # Overlay, consumed by other flakes
  overlays."<name>" = final: prev: { };
  # Default overlay
  overlays.default = final: prev: { };
  # Nixos module, consumed by other flakes
  nixosModules."<name>" = { config, ... }: { options = {}; config = {}; };
  # Default module
  nixosModules.default = { config, ... }: { options = {}; config = {}; };
  # Used with `nixos-rebuild switch --flake .#<hostname>`
  # nixosConfigurations."<hostname>".config.system.build.toplevel must be a derivation
  nixosConfigurations."<hostname>" = {};
  # Used by `nix develop .#<name>`
  devShells."<system>"."<name>" = derivation;
  # Used by `nix develop`
  devShells."<system>".default = derivation;
  # Hydra build jobs
  hydraJobs."<attr>"."<system>" = derivation;
  # Used by `nix flake init -t <flake>#<name>`
  templates."<name>" = {
    path = "<store-path>";
    description = "template description goes here?";
  };
  # Used by `nix flake init -t <flake>`
  templates.default = { path = "<store-path>"; description = ""; };
}
</syntaxhighlight>

<div lang="en" dir="ltr" class="mw-content-ltr">
You can also define additional arbitrary attributes, but these are the outputs that Nix knows about.
</div>

<div lang="en" dir="ltr" class="mw-content-ltr">
== Core usage patterns ==
</div>

<div lang="en" dir="ltr" class="mw-content-ltr">
=== Making your evaluations pure ===
</div>

<div lang="en" dir="ltr" class="mw-content-ltr">
Nix flakes are evaluated in a pure evaluation mode, meaning that access to the external environment is restricted to ensure reproducibility. To maintain purity when working with flakes, consider the following:
</div>

<div lang="en" dir="ltr" class="mw-content-ltr">
* {{Nixpkgs Manual|name=fetchurl|anchor=#sec-pkgs-fetchers-fetchurl-inputs}} and {{Nixpkgs Manual|name=fetchzip|anchor=#sec-pkgs-fetchers-fetchzip-inputs}} require a <code>sha256</code> argument to be considered pure.
</div>

<div lang="en" dir="ltr" class="mw-content-ltr">
* <code>builtins.currentSystem</code> is non-hermetic and impure as it reflects the host system performing the evauluation. This can usually be avoided by passing the system (i.e., x86_64-linux) explicitly to derivations requiring it.
</div>

<div lang="en" dir="ltr" class="mw-content-ltr">
*  <code>builtins.getEnv</code> is also impure. Avoid reading from environment variables and likewise, do not reference files outside of the flake's directory.
</div>

<div lang="en" dir="ltr" class="mw-content-ltr">
=== Defining a flake for multiple architectures ===
</div>

<div lang="en" dir="ltr" class="mw-content-ltr">
Flakes force you to specify a program for each supported architecture. An example below shows how to write a flake that targets multiple architectures.
</div>

<div lang="en" dir="ltr" class="mw-content-ltr">
<syntaxhighlight lang="nix">
{
  description = "A flake targeting multiple architectures";
</div>

  <div lang="en" dir="ltr" class="mw-content-ltr">
inputs = {
    nixpkgs.url = "github:nixos/nixpkgs?ref=nixos-unstable";
  };
</div>

  <div lang="en" dir="ltr" class="mw-content-ltr">
outputs = { self, nixpkgs }: let
    systems = [ "x86_64-linux" "aarch64-linux" ];
    forAllSystems = f: builtins.listToAttrs (map (system: {
      name = system;
      value = f system;
    }) systems);
  in {
    packages = forAllSystems (system: let
      pkgs = nixpkgs.legacyPackages.${system};
    in {
      hello = pkgs.hello;
      default = pkgs.hello;
    });
  };
}
</syntaxhighlight>
</div>

<div lang="en" dir="ltr" class="mw-content-ltr">
You can also use third-parties projects like [[Flake Utils|flake-utils]] or [[Flake Parts|flake-parts]] that automatically provide code to avoid this boilerplate. To avoid re-defining the program multiple times, refer to [[Flake Utils#Defining a flake for multiple architectures]]
</div>

<div lang="en" dir="ltr" class="mw-content-ltr">
=== Using overlays ===
</div> 

<div lang="en" dir="ltr" class="mw-content-ltr">
To use [[Overlays]] with flakes, refer to [[Overlays#In a Nix flake]] page.
</div>

<span id="Enable_unfree_software"></span>
<div class="mw-translate-fuzzy">
== Включить несвободное ПО ==
</div>

<div lang="en" dir="ltr" class="mw-content-ltr">
To allow for [[Unfree software|unfree software]] in a flake project, you need to explicitly allow it by setting <code>config.allowUnree = true;</code> when importing Nixpkgs.
</div>

<div lang="en" dir="ltr" class="mw-content-ltr">
<syntaxhighlight lang="nix">
{
  inputs.nixpkgs.url = "github:nixos/nixpkgs?ref=nixos-unstable";
  outputs = { self, nixpkgs, flake-compat }:
    let
      system = "x86_64-linux";
      pkgs = import nixpkgs { inherit system; config.allowUnfree = true;};
    in {
      ...
    };
}
</syntaxhighlight>
</div> 

<div lang="en" dir="ltr" class="mw-content-ltr">
== NixOS configuration with flakes ==
</div>

<div lang="en" dir="ltr" class="mw-content-ltr">
It is possible to manage a [[NixOS]] system configuration using flakes, gaining the benefits of reproducible, declarative inputs and streamlined updates.
</div>

<div lang="en" dir="ltr" class="mw-content-ltr">
For details and examples, see [[NixOS system configuration#Defining NixOS as a flake]].
</div>

<span id="Development_tricks"></span>
== Трюки для разработки ==

<span id="Automatically_switch_nix_shells_with_direnv"></span>
<div class="mw-translate-fuzzy">
=== Автоматическое переключение оболочек nix с nix-direnv ===
</div>

<div lang="en" dir="ltr" class="mw-content-ltr">
It is possible to automatically activate different Nix shells when navigating between project directories by using [[Direnv]]. Additional Nix integration with Direnv can be achieved with [https://github.com/nix-community/nix-direnv nix-direnv].
</div>

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=== Pushing Flakes to Cachix ===
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https://docs.cachix.org/pushing#flakes

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=== Flake support in projects without flakes ===
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The [https://github.com/edolstra/flake-compat flake-compat] library provides a compatibility layer that allows projects using traditional <code>default.nix</code> and <code>shell.nix</code> files to operate with flakes. For more details and usage examples, see the [[Flake Compat]] page.
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Another project that allows consuming flakes from non-flake projects is [https://github.com/fricklerhandwerk/flake-inputs flake-inputs].
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=== Accessing flakes from Nix expressions ===
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If you want to access a flake from within a regular Nix expression on a system that has flakes enabled, you can use something like <code>(builtins.getFlake "/path/to/directory").packages.x86_64-linux.default</code>, where 'directory' is the directory that contains your <code>flake.nix</code>.
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=== Efficiently build multiple flake outputs ===
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To push ''all'' flake outputs automatically, checkout [https://github.com/srid/devour-flake#usage devour-flake].
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=== Build a package added in a PR ===
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<syntaxHighlight>
nix build github:nixos/nixpkgs?ref=pull/<PR_NUMBER>/head#<PACKAGE>
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this allows building a package that has not yet been added to nixpkgs.
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note that this will download a full source tarball of nixpkgs.  if you already have a local clone, using that may be faster due to delta compression:
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<syntaxHighlight>
git fetch upstream pull/<PR_NUMBER>/head && git checkout FETCH_HEAD && nix build .#PACKAGE
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this allows building a package that has not yet been added to nixpkgs.
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=== How to add a file locally in git but not include it in commits ===
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When a [[git]] folder exists, flake will only copy files added in git to maximize reproducibility (this way if you forgot to add a local file in your repo, you will directly get an error when you try to compile it). However, for development purpose you may want to create an alternative flake file, for instance containing configuration for your preferred editors as described [https://discourse.nixos.org/t/local-personal-development-tools-with-flakes/22714/8 here]… of course without committing this file since it contains only your own preferred tools. You can do so by doing something like that (say for a file called <code>extra/flake.nix</code>):
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<syntaxHighlight>
git add --intent-to-add extra/flake.nix
git update-index --skip-worktree --assume-unchanged extra/flake.nix
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=== Rapid iteration of a direct dependency ===
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One common pain point with using Nix as a development environment is the need to completely rebuild dependencies and re-enter the dev shell every time they are updated. The <code>nix develop --redirect <flake> <directory></code> command allows you to provide a mutable dependency to your shell as if it were built by Nix.
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Consider a situation where your executable, <code>consumexe</code>, depends on a library, <code>libdep</code>. You're trying to work on both at the same time, where changes to <code>libdep</code> are reflected in real time for <code>consumexe</code>. This workflow can be achieved like so:
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<syntaxHighlight lang=bash>
cd ~/libdep-src-checkout/
nix develop # Or `nix-shell` if applicable.
export prefix="./install" # configure nix to install it here
buildPhase   # build it like nix does
installPhase # install it like nix does
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Now that you've built the dependency, <code>consumexe</code> can take it as an input. '''In another terminal''':
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<syntaxHighlight lang=bash>
cd ~/consumexe-src-checkout/
nix develop --redirect libdep ~/libdep-src-checkout/install
echo $buildInputs | tr " " "\n" | grep libdep
# Output should show ~/libdep-src-checkout/ so you know it worked
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If Nix warns you that your redirected flake isn't actually used as an input to the evaluated flake, try using the <code>--inputs-from .</code> flag. If all worked well you should be able to <code>buildPhase && installPhase</code> when the dependency changes and rebuild your consumer with the new version ''without'' exiting the development shell.
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<span id="See_also"></span>
== См. также ==

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=== Official sources ===
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* [https://nix.dev/concepts/flakes Flakes] - nix.dev
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* [https://nixos.org/manual/nix/unstable/command-ref/new-cli/nix3-flake.html Nix flake command reference manual] - Many additional details about flakes, and their parts.
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* [https://github.com/NixOS/nix/blob/master/src/nix/flake.md spec describing flake inputs in more detail]
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* [https://github.com/NixOS/rfcs/pull/49 RFC 49] (2019) - Original flakes specification
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=== Guides ===
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* [https://jade.fyi/blog/flakes-arent-real/ Flakes aren't real and can't hurt you] (Jade Lovelace, 2024)
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* [https://github.com/ryan4yin/nixos-and-flakes-book NixOS & Flakes Book](Ryan4yin, 2023) - 🛠️ ❤️ An unofficial NixOS & Flakes book for beginners.
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* [https://xeiaso.net/blog/nix-flakes-1-2022-02-21 Nix Flakes: an Introduction] (Xe Iaso, 2022)
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* [https://serokell.io/blog/practical-nix-flakes Practical Nix Flakes] (Alexander Bantyev, 2021) - Intro article on working with Nix and Flakes
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* [https://www.tweag.io/blog/2020-05-25-flakes/ Nix Flakes, Part 1: An introduction and tutorial] (Eelco Dolstra, 2020)
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* [https://www.tweag.io/blog/2020-06-25-eval-cache/ Nix Flakes, Part 2: Evaluation caching] (Eelco Dolstra, 2020)
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* [https://www.tweag.io/blog/2020-07-31-nixos-flakes/ Nix Flakes, Part 3: Managing NixOS systems] (Eelco Dolstra, 2020)
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* [https://www.youtube.com/watch?v=QXUlhnhuRX4&list=PLgknCdxP89RcGPTjngfNR9WmBgvD_xW0l Nix flakes 101: Introduction to nix flakes] (Jörg Thalheim, 2020) YouTube video
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=== Useful flake modules ===
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* [[Flake Utils|flake-utils]]: Library to avoid some boiler-code when writing flakes
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* [[Flake Parts|flake-parts]]: Library to help write modular and organized flakes
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* [[Flake Compat|flake-compat]]: A compatibility layer for flakes
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* [https://github.com/nix-community/todomvc-nix building Rust and Haskell flakes]
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{{references}}
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[[Category:Software]]
[[Category:Nix]]
[[Category:Nix Language]]
[[Category:Flakes]]