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. See Version Numbers, for guidelines.
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 (see Build Systems). This is a list, typically containing sequential keyword-value pairs, as in this example:
The exact set of supported keywords depends on the build system
(see Build Systems), but you will find that almost all of them honor
#:phases keyword in particular lets you
modify the set of build phases for your package (see Build Phases).
These fields list dependencies of the package. Each element of these lists is either a package, origin, or other “file-like object” (see G-Expressions); to specify the output of that file-like object that should be used, pass a two-element list where the second element is the output (see Packages with Multiple Outputs, for more on package outputs). For example, the list below specifies three inputs:
(list libffi libunistring `(,glib "bin")) ;the "bin" output of GLib
In the example above, the
"out" output of
libunistring is used.
Compatibility Note: Until version 1.3.0, input lists were 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 defaults to
"out". For example, the list below is equivalent to the one above, but using the old input style:;; Old input style (deprecated). `(("libffi" ,libffi) ("libunistring" ,libunistring) ("glib:bin" ,glib "bin")) ;the "bin" output of GLib
This style is now deprecated; it is still supported but support will be removed in a future version. It should not be used for new package definitions. See Invoking guix style, on how to migrate to the new style.
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. See Search Paths, for more on search path specifications.
As for inputs, the distinction between
search-paths only matters when cross-compiling. In a
exclusively to native inputs whereas
search-paths applies only to
Packages such as cross-compilers care about target inputs—for
instance, our (modified) GCC cross-compiler has
search-paths, which allows it to
pick .h files for the target system and not those of
native inputs. For the majority of packages though, only
native-search-paths makes sense.
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, as a string in Texinfo syntax.
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) (list this-package) '())))
It is an error to refer to
this-package outside a package definition.
The following helper procedures are provided to help deal with package inputs.
Look up name among package’s inputs (or native, propagated,
or direct inputs). Return it if found,
name is the name of a package depended on. Here’s how you might use it:
(use-modules (guix packages) (gnu packages base)) (lookup-package-direct-input coreutils "gmp") ⇒ #<package email@example.com …>
In this example we obtain the
gmp package that is among the
direct inputs of
Sometimes you will want to obtain the list of inputs needed to
develop a package—all the inputs that are visible when the
package is compiled. This is what the
Return the list of inputs required by package for development
purposes on system. When target is true, return the inputs
needed to cross-compile package from system to
triplet, where triplet is a triplet such as
Note that the result includes both explicit inputs and implicit
inputs—inputs automatically added by the build system (see Build Systems). Let us take the
hello package to illustrate that:
(use-modules (gnu packages base) (guix packages)) hello ⇒ #<package firstname.lastname@example.org gnu/packages/base.scm:79 7f585d4f6790> (package-direct-inputs hello) ⇒ () (package-development-inputs hello) ⇒ (("source" …) ("tar" #<package email@example.com …>) …)
In this example,
package-direct-inputs returns the empty list,
hello has zero explicit dependencies. Conversely,
package-development-inputs includes inputs implicitly added by
gnu-build-system that are required to build
gzip, GCC, libc, Bash, and more. To visualize it,
hello would show you explicit inputs, whereas
guix graph -t
bag hello would include implicit inputs (see Invoking guix graph).
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.