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# Build helpers {#part-builders}

     

       
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A build helper is a function that produces derivations.

     

       
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:::{.warning}

     

       
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This is not to be confused with the [`builder` argument of the Nix `derivation` primitive](https://nixos.org/manual/nix/unstable/language/derivations.html), which refers to the executable that produces the build result, or [remote builder](https://nixos.org/manual/nix/stable/advanced-topics/distributed-builds.html), which refers to a remote  machine that could run such an executable.

     

       
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:::

     

       
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Such a function is usually designed to abstract over a typical workflow for a given programming language or framework.

     

       
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This allows declaring a build recipe by setting a limited number of options relevant to the particular use case instead of using the `derivation` function directly.

     

       
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[`stdenv.mkDerivation`](#part-stdenv) is the most widely used build helper, and serves as a basis for many others.

     

       
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In addition, it offers various options to customize parts of the builds.

     

       
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There is no uniform interface for build helpers.

     

       
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[Trivial build helpers](#chap-trivial-builders) and [fetchers](#chap-pkgs-fetchers) have various input types for convenience.

     

       
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[Language- or framework-specific build helpers](#chap-language-support) usually follow the style of `stdenv.mkDerivation`, which accepts an attribute set or a fixed-point function taking an attribute set.

     

       
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```{=include=} chapters

     

       
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build-helpers/fetchers.chapter.md

     

       
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build-helpers/trivial-build-helpers.chapter.md