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The purpose of
guix shell is to make it easy to create one-off
software environments, without changing one’s profile. It is typically used
to create development environments; it is also a convenient way to run
applications without “polluting” your profile.
guix shellcommand was recently introduced to supersede
guix environment(see Invocando guix environment). If you are familiar with
guix environment, you will notice that it is similar but also—we hope!—more convenient.
The general syntax is:
guix shell [options] [package…]
The following example creates an environment containing Python and NumPy,
building or downloading any missing package, and runs the
command in that environment:
guix shell python python-numpy -- python3
Development environments can be created as in the example below, which spawns an interactive shell containing all the dependencies and environment variables needed to work on Inkscape:
guix shell --development inkscape
Exiting the shell places the user back in the original environment before
guix shell was invoked. The next garbage collection
(see Invocando guix gc) may clean up packages that were installed in the
environment and that are no longer used outside of it.
As an added convenience,
guix shell will try to do what you mean
when it is invoked interactively without any other arguments as in:
If it finds a manifest.scm in the current working directory or any of
its parents, it uses this manifest as though it was given via
--manifest. Likewise, if it finds a guix.scm in the same
directories, it uses it to build a development profile as though both
--file were present. In either case, the
file will only be loaded if the directory it resides in is listed in
~/.config/guix/shell-authorized-directories. This provides an easy
way to define, share, and enter development environments.
By default, the shell session or command runs in an augmented
environment, where the new packages are added to search path environment
variables such as
PATH. You can, instead, choose to create an
isolated environment containing nothing but the packages you asked
for. Passing the --pure option clears environment variable
definitions found in the parent environment14; passing --container goes one step further by
spawning a container isolated from the rest of the system:
guix shell --container emacs gcc-toolchain
The command above spawns an interactive shell in a container where nothing
gcc-toolchain, and their dependencies is
available. The container lacks network access and shares no files other
than the current working directory with the surrounding environment. This
is useful to prevent access to system-wide resources such as /usr/bin
on foreign distros.
This --container option can also prove useful if you wish to run a
security-sensitive application, such as a web browser, in an isolated
environment. For example, the command below launches Ungoogled-Chromium in
an isolated environment, this time sharing network access with the host and
DISPLAY environment variable, but without even sharing
the current directory:
guix shell --container --network --no-cwd ungoogled-chromium \ --preserve='^DISPLAY$' -- chromium
guix shell defines the
GUIX_ENVIRONMENT variable in the
shell it spawns; its value is the file name of the profile of this
environment. This allows users to, say, define a specific prompt for
development environments in their .bashrc (see Bash Startup Files in The GNU Bash Reference Manual):
if [ -n "$GUIX_ENVIRONMENT" ] then export PS1="\u@\h \w [dev]\$ " fi
... or to browse the profile:
$ ls "$GUIX_ENVIRONMENT/bin"
The available options are summarized below.
Set up the environment and check whether the shell would clobber environment
variables. It’s a good idea to use this option the first time you run
guix shell for an interactive session to make sure your setup is
For example, if the shell modifies the
PATH environment variable,
report it since you would get a different environment than what you asked
Such problems usually indicate that the shell startup files are unexpectedly modifying those environment variables. For example, if you are using Bash, make sure that environment variables are set or modified in ~/.bash_profile and not in ~/.bashrc—the former is sourced only by log-in shells. See Bash Startup Files in The GNU Bash Reference Manual, for details on Bash start-up files.
guix shell to include in the environment the dependencies of
the following package rather than the package itself. This can be combined
with other packages. For instance, the command below starts an interactive
shell containing the build-time dependencies of GNU Guile, plus
Autoconf, Automake, and Libtool:
guix shell -D guile autoconf automake libtool
Create an environment for the package or list of packages that expr evaluates to.
For example, running:
guix shell -D -e '(@ (gnu packages maths) petsc-openmpi)'
starts a shell with the environment for this specific variant of the PETSc package.
guix shell -e '(@ (gnu) %base-packages)'
starts a shell with all the base system packages available.
The above commands only use the default output of the given packages. To select other outputs, two element tuples can be specified:
guix shell -e '(list (@ (gnu packages bash) bash) "include")'
for information on how to write a manifest for the development environment
of a package.
Create an environment containing the package or list of packages that the code within file evaluates to.
As an example, file might contain a definition like this (see Definindo pacotes):
(use-modules (guix) (gnu packages gdb) (gnu packages autotools) (gnu packages texinfo)) ;; Augment the package definition of GDB with the build tools ;; needed when developing GDB (and which are not needed when ;; simply installing it.) (package (inherit gdb) (native-inputs (modify-inputs (package-native-inputs gdb) (prepend autoconf-2.64 automake texinfo))))
With the file above, you can enter a development environment for GDB by running:
guix shell -D -f gdb-devel.scm
Create an environment for the packages contained in the manifest object returned by the Scheme code in file. This option can be repeated several times, in which case the manifests are concatenated.
This is similar to the same-named option in
(see --manifest) and uses the same manifest
See Writing Manifests, for information on how to write a manifest. See --export-manifest below on how to obtain a first manifest.
Write to standard output a manifest suitable for --manifest corresponding to given command-line options.
This is a way to “convert” command-line arguments into a manifest. For example, imagine you are tired of typing long lines and would like to get a manifest equivalent to this command line:
guix shell -D guile git emacs emacs-geiser emacs-geiser-guile
Just add --export-manifest to the command line above:
guix shell --export-manifest \ -D guile git emacs emacs-geiser emacs-geiser-guile
... and you get a manifest along these lines:
(concatenate-manifests (list (specifications->manifest (list "git" "emacs" "emacs-geiser" "emacs-geiser-guile")) (package->development-manifest (specification->package "guile"))))
You can store it into a file, say manifest.scm, and from there pass
guix shell or indeed pretty much any
guix shell -m manifest.scm
Voilà, you’ve converted a long command line into a manifest! That conversion process honors package transformation options (see Opções de transformação de pacote) so it should be lossless.
Create an environment containing the packages installed in profile.
guix package (see Invocando guix package) to create and
Unset existing environment variables when building the new environment, except those specified with --preserve (see below). This has the effect of creating an environment in which search paths only contain package inputs.
When used alongside --pure, preserve the environment variables matching regexp—in other words, put them on a “white list” of environment variables that must be preserved. This option can be repeated several times.
guix shell --pure --preserve=^SLURM openmpi … \ -- mpirun …
This example runs
mpirun in a context where the only environment
variables defined are
PATH, environment variables whose name starts
with ‘SLURM’, as well as the usual “precious” variables (
Display the environment variable definitions that make up the environment.
Attempt to build for system—e.g.,
Run command within an isolated container. The current working directory outside the container is mapped inside the container. Additionally, unless overridden with --user, a dummy home directory is created that matches the current user’s home directory, and /etc/passwd is configured accordingly.
The spawned process runs as the current user outside the container. Inside the container, it has the same UID and GID as the current user, unless --user is passed (see below).
For containers, share the network namespace with the host system. Containers created without this flag only have access to the loopback device.
For containers, link the environment profile to ~/.guix-profile
within the container and set
GUIX_ENVIRONMENT to that. This is
equivalent to making ~/.guix-profile a symlink to the actual profile
within the container. Linking will fail and abort the environment if the
directory already exists, which will certainly be the case if
shell was invoked in the user’s home directory.
Certain packages are configured to look in ~/.guix-profile for configuration files and data;15 --link-profile allows these programs to behave as expected within the environment.
For containers, use the username user in place of the current user. The generated /etc/passwd entry within the container will contain the name user, the home directory will be /home/user, and no user GECOS data will be copied. Furthermore, the UID and GID inside the container are 1000. user need not exist on the system.
Additionally, any shared or exposed path (see --share and --expose respectively) whose target is within the current user’s home directory will be remapped relative to /home/USER; this includes the automatic mapping of the current working directory.
# will expose paths as /home/foo/wd, /home/foo/test, and /home/foo/target cd $HOME/wd guix shell --container --user=foo \ --expose=$HOME/test \ --expose=/tmp/target=$HOME/target
While this will limit the leaking of user identity through home paths and each of the user fields, this is only one useful component of a broader privacy/anonymity solution—not one in and of itself.
For containers, the default behavior is to share the current working directory with the isolated container and immediately change to that directory within the container. If this is undesirable, --no-cwd will cause the current working directory to not be automatically shared and will change to the user’s home directory within the container instead. See also --user.
For containers, --expose (resp. --share) exposes the file system source from the host system as the read-only (resp. writable) file system target within the container. If target is not specified, source is used as the target mount point in the container.
The example below spawns a Guile REPL in a container in which the user’s home directory is accessible read-only via the /exchange directory:
guix shell --container --expose=$HOME=/exchange guile -- guile
For containers, create the symbolic links specified by spec, as documented in pack-symlink-option.
When used with --container, emulate a Filesystem Hierarchy Standard (FHS) configuration within the container, providing /bin, /lib, and other directories and files specified by the FHS.
As Guix deviates from the FHS specification, this option sets up the container to more closely mimic that of other GNU/Linux distributions. This is useful for reproducing other development environments, testing, and using programs which expect the FHS specification to be followed. With this option, the container will include a version of glibc that will read /etc/ld.so.cache within the container for the shared library cache (contrary to glibc in regular Guix usage) and set up the expected FHS directories: /bin, /etc, /lib, and /usr from the container’s profile.
In most cases,
guix shell caches the environment so that
subsequent uses are instantaneous. Least-recently used cache entries are
periodically removed. The cache is also invalidated, when using
--file or --manifest, anytime the corresponding file is
The --rebuild-cache forces the cached environment to be refreshed.
This is useful when using --file or --manifest and the
manifest.scm file has external dependencies,
or if its behavior depends, say, on environment variables.
Make file a symlink to the profile for this environment, and register it as a garbage collector root.
This is useful if you want to protect your environment from garbage collection, to make it “persistent”.
When this option is omitted,
guix shell caches profiles so that
subsequent uses of the same environment are instantaneous—this is
comparable to using --root except that
guix shell takes
care of periodically removing the least-recently used garbage collector
In some cases,
guix shell does not cache profiles—e.g., if
transformation options such as --with-latest are used. In those
cases, the environment is protected from garbage collection only for the
duration of the
guix shell session. This means that next time you
recreate the same environment, you could have to rebuild or re-download
See Invocando guix gc, for more on GC roots.
guix shell also supports all of the common build options that
guix build supports (see Opções de compilação comum) as well as
package transformation options (see Opções de transformação de pacote).
Be sure to use the
--check option the first time you use
interactively to make sure the shell does not undo the effect of
For example, the
package inspects ~/.guix-profile/share/fonts for additional fonts.
Next: Invocando guix environment, Up: Desenvolvimento [Contents][Index]