This section summarizes all the options available in
declarations (see Defining Packages).
This is the data type representing a package recipe.
The name of the package, as a string.
The version of the package, as a string.
An object telling how the source code for the package should be
acquired. Most of the time, this is an
origin object, which
denotes a file fetched from the Internet (see origin Reference). It
can also be any other “file-like” object such as a
which denotes a file from the local file system (see
The build system that should be used to build the package (see Build Systems).
The arguments that should be passed to the build system. This is a list, typically containing sequential keyword-value pairs.
These fields list dependencies of the package. Each one is a list of
tuples, where each tuple has a label for the input (a string) as its
first element, a package, origin, or derivation as its second element,
and optionally the name of the output thereof that should be used, which
"out" (see Packages with Multiple Outputs, for
more on package outputs). For example, the list below specifies three
`(("libffi" ,libffi) ("libunistring" ,libunistring) ("glib:bin" ,glib "bin")) ;the "bin" output of Glib
The distinction between
necessary when considering cross-compilation. When cross-compiling,
dependencies listed in
inputs are built for the target
architecture; conversely, dependencies listed in
are built for the architecture of the build machine.
native-inputs is typically used to list tools needed at
build time, but not at run time, such as Autoconf, Automake, pkg-config,
Gettext, or Bison.
guix lint can report likely mistakes in
this area (see Invoking guix lint).
propagated-inputs is similar to
inputs, but the
specified packages will be automatically installed to profiles
(see the role of profiles in Guix) alongside the package
they belong to (see
package, for information on how
guix package deals with
For example this is necessary when packaging a C/C++ library that needs
headers of another library to compile, or when a pkg-config file refers
to another one via its
Another example where
propagated-inputs is useful is for languages
that lack a facility to record the run-time search path akin to the
RUNPATH of ELF files; this includes Guile, Python, Perl, and
more. When packaging libraries written in those languages, ensure they
can find library code they depend on at run time by listing run-time
propagated-inputs rather than
The list of output names of the package. See Packages with Multiple Outputs, for typical uses of additional outputs.
A list of
search-path-specification objects describing
search-path environment variables honored by the package.
This must be either
#f or a package object that will be used as a
replacement for this package. See grafts,
A one-line description of the package.
A more elaborate description of the package.
The license of the package; a value from
or a list of such values.
The URL to the home-page of the package, as a string.
The list of systems supported by the package, as strings of the form
architecture-kernel, for example
location(default: source location of the
The source location of the package. It is useful to override this when inheriting from another package, in which case this field is not automatically corrected.
When used in the lexical scope of a package field definition, this identifier resolves to the package being defined.
The example below shows how to add a package as a native input of itself when cross-compiling:
(package (name "guile") ;; ... ;; When cross-compiled, Guile, for example, depends on ;; a native version of itself. Add it here. (native-inputs (if (%current-target-system) `(("self" ,this-package)) '())))
It is an error to refer to
this-package outside a package definition.
Because packages are regular Scheme objects that capture a complete dependency graph and associated build procedures, it is often useful to write procedures that take a package and return a modified version thereof according to some parameters. Below are a few examples.
Return a variant of package that uses toolchain instead of
the default GNU C/C++ toolchain. toolchain must be a list of
inputs (label/package tuples) providing equivalent functionality, such
The example below returns a variant of the
hello package built
with GCC 10.x and the rest of the GNU tool chain (Binutils and the
GNU C Library) instead of the default tool chain:
(let ((toolchain (specification->package "gcc-toolchain@10"))) (package-with-c-toolchain hello `(("toolchain" ,toolchain))))
The build tool chain is part of the implicit inputs of packages—it’s usually not listed as part of the various “inputs” fields and is instead pulled in by the build system. Consequently, this procedure works by changing the build system of package so that it pulls in toolchain instead of the defaults. Build Systems, for more on build systems.