5.1.2 Package Transformation Options

Another set of command-line options supported by guix build and also guix package are package transformation options. These are options that make it possible to define package variants—for instance, packages built from different source code. This is a convenient way to create customized packages on the fly without having to type in the definitions of package variants (see Defining Packages).

--with-source=source

Use source as the source of the corresponding package. source must be a file name or a URL, as for guix download (see Invoking guix download).

The “corresponding package” is taken to be the one specified on the command line the name of which matches the base of source—e.g., if source is /src/guile-2.0.10.tar.gz, the corresponding package is guile. Likewise, the version string is inferred from source; in the previous example, it is 2.0.10.

This option allows users to try out versions of packages other than the one provided by the distribution. The example below downloads ed-1.7.tar.gz from a GNU mirror and uses that as the source for the ed package:

guix build ed --with-source=mirror://gnu/ed/ed-1.7.tar.gz

As a developer, --with-source makes it easy to test release candidates:

guix build guile --with-source=../guile-2.0.9.219-e1bb7.tar.xz

… or to build from a checkout in a pristine environment:

$ git clone git://git.sv.gnu.org/guix.git
$ guix build guix --with-source=./guix

--with-input=package=replacement

Replace dependency on package by a dependency on replacement. package must be a package name, and replacement must be a package specification such as guile or guile@1.8.

For instance, the following command builds Guix, but replaces its dependency on the current stable version of Guile with a dependency on the legacy version of Guile, guile@2.0:

guix build --with-input=guile=guile@2.0 guix

This is a recursive, deep replacement. So in this example, both guix and its dependency guile-json (which also depends on guile) get rebuilt against guile@2.0.

This is implemented using the package-input-rewriting Scheme procedure (see package-input-rewriting).

--with-graft=package=replacement

This is similar to --with-input but with an important difference: instead of rebuilding the whole dependency chain, replacement is built and then grafted onto the binaries that were initially referring to package. See Security Updates, for more information on grafts.

For example, the command below grafts version 3.5.4 of GnuTLS onto Wget and all its dependencies, replacing references to the version of GnuTLS they currently refer to:

guix build --with-graft=gnutls=gnutls@3.5.4 wget

This has the advantage of being much faster than rebuilding everything. But there is a caveat: it works if and only if package and replacement are strictly compatible—for example, if they provide a library, the application binary interface (ABI) of those libraries must be compatible. If replacement is somehow incompatible with package, then the resulting package may be unusable. Use with care!