<appendix xmlns="http://docbook.org/ns/docbook"
          xmlns:xlink="http://www.w3.org/1999/xlink"
          xml:id="chap-hacking">

<title>Hacking</title>

<para>This section provides some notes on how to hack on Nix. To get
the latest version of Nix from GitHub:
<screen>
$ git clone https://github.com/NixOS/nix.git
$ cd nix
</screen>
</para>

<para>To build Nix for the current operating system/architecture use

<screen>
$ nix-build
</screen>

or if you have a flakes-enabled nix:

<screen>
$ nix build
</screen>

This will build <literal>defaultPackage</literal> attribute defined in the <literal>flake.nix</literal> file.

To build for other platforms add one of the following suffixes to it: aarch64-linux,
i686-linux, x86_64-darwin, x86_64-linux.

i.e.

<screen>
nix-build -A defaultPackage.x86_64-linux
</screen>

</para>

<para>To build all dependencies and start a shell in which all
environment variables are set up so that those dependencies can be
found:
<screen>
$ nix-shell
</screen>
To build Nix itself in this shell:
<screen>
[nix-shell]$ ./bootstrap.sh
[nix-shell]$ ./configure $configureFlags
[nix-shell]$ make -j $NIX_BUILD_CORES
</screen>
To install it in <literal>$(pwd)/inst</literal> and test it:
<screen>
[nix-shell]$ make install
[nix-shell]$ make installcheck
[nix-shell]$ ./inst/bin/nix --version
nix (Nix) 2.4
</screen>

If you have a flakes-enabled nix you can replace:

<screen>
$ nix-shell
</screen>

by:

<screen>
$ nix develop
</screen>

</para>

</appendix>
