6.1.1 Basic setup with manifests

A Guix profile can be set up via a manifest. A manifest is a snippet of Scheme code that specifies the set of packages you want to have in your profile; it looks like this:

(specifications->manifest
  '("package-1"
    ;; Version 1.3 of package-2.
    "package-2@1.3"
    ;; The "lib" output of package-3.
    "package-3:lib"
    ; ...
    "package-N"))

See Writing Manifests in GNU Guix Reference Manual, for more information about the syntax.

We can create a manifest specification per profile and install them this way:

GUIX_EXTRA_PROFILES=$HOME/.guix-extra-profiles
mkdir -p "$GUIX_EXTRA_PROFILES"/my-project # if it does not exist yet
guix package --manifest=/path/to/guix-my-project-manifest.scm \
 --profile="$GUIX_EXTRA_PROFILES"/my-project/my-project

Here we set an arbitrary variable ‘GUIX_EXTRA_PROFILES’ to point to the directory where we will store our profiles in the rest of this article.

Placing all your profiles in a single directory, with each profile getting its own sub-directory, is somewhat cleaner. This way, each sub-directory will contain all the symlinks for precisely one profile. Besides, “looping over profiles” becomes obvious from any programming language (e.g. a shell script) by simply looping over the sub-directories of ‘$GUIX_EXTRA_PROFILES’.

Note that it’s also possible to loop over the output of

guix package --list-profiles

although you’ll probably have to filter out ~/.config/guix/current.

To enable all profiles on login, add this to your ~/.bash_profile (or similar):

for i in $GUIX_EXTRA_PROFILES/*; do
  profile=$i/$(basename "$i")
  if [ -f "$profile"/etc/profile ]; then
    GUIX_PROFILE="$profile"
    . "$GUIX_PROFILE"/etc/profile
  fi
  unset profile
done

Note to Guix System users: the above reflects how your default profile ~/.guix-profile is activated from /etc/profile, that latter being loaded by ~/.bashrc by default.

You can obviously choose to only enable a subset of them:

for i in "$GUIX_EXTRA_PROFILES"/my-project-1 "$GUIX_EXTRA_PROFILES"/my-project-2; do
  profile=$i/$(basename "$i")
  if [ -f "$profile"/etc/profile ]; then
    GUIX_PROFILE="$profile"
    . "$GUIX_PROFILE"/etc/profile
  fi
  unset profile
done

When a profile is off, it’s straightforward to enable it for an individual shell without "polluting" the rest of the user session:

GUIX_PROFILE="path/to/my-project" ; . "$GUIX_PROFILE"/etc/profile

The key to enabling a profile is to source its ‘etc/profile’ file. This file contains shell code that exports the right environment variables necessary to activate the software contained in the profile. It is built automatically by Guix and meant to be sourced. It contains the same variables you would get if you ran:

guix package --search-paths=prefix --profile=$my_profile"

Once again, see Invoking guix package in GNU Guix Reference Manual for the command line options.

To upgrade a profile, simply install the manifest again:

guix package -m /path/to/guix-my-project-manifest.scm \
 -p "$GUIX_EXTRA_PROFILES"/my-project/my-project

To upgrade all profiles, it’s easy enough to loop over them. For instance, assuming your manifest specifications are stored in ~/.guix-manifests/guix-$profile-manifest.scm, with ‘$profile’ being the name of the profile (e.g. "project1"), you could do the following in Bourne shell:

for profile in "$GUIX_EXTRA_PROFILES"/*; do
  guix package --profile="$profile" \
   --manifest="$HOME/.guix-manifests/guix-$profile-manifest.scm"
done

Each profile has its own generations:

guix package -p "$GUIX_EXTRA_PROFILES"/my-project/my-project --list-generations

You can roll-back to any generation of a given profile:

guix package -p "$GUIX_EXTRA_PROFILES"/my-project/my-project --switch-generations=17

Finally, if you want to switch to a profile without inheriting from the current environment, you can activate it from an empty shell:

env -i $(which bash) --login --noprofile --norc
. my-project/etc/profile