Merge branch 'wip-guix-home'

18 files changed, 4053 insertions, 4 deletions

diff --git a/Makefile.am b/Makefile.am
index 042cf28464..b66789fa0b 100644
--- a/Makefile.am
+++ b/Makefile.am
@@ -15,6 +15,7 @@
 # Copyright © 2018 Alex Vong <alexvong1995@gmail.com>
 # Copyright © 2019 Efraim Flashner <efraim@flashner.co.il>
 # Copyright © 2021 Chris Marusich <cmmarusich@gmail.com>
+# Copyright © 2021 Andrew Tropin <andrew@trop.in>
 #
 # This file is part of GNU Guix.
 #
@@ -295,6 +296,8 @@ MODULES =					\
   guix/scripts/system.scm			\
   guix/scripts/system/search.scm		\
   guix/scripts/system/reconfigure.scm		\
+  guix/scripts/home.scm			\
+  guix/scripts/home/import.scm			\
   guix/scripts/lint.scm				\
   guix/scripts/challenge.scm			\
   guix/scripts/import/crate.scm			\
diff --git a/doc/guix.texi b/doc/guix.texi
index 4bf14014eb..7956652050 100644
--- a/doc/guix.texi
+++ b/doc/guix.texi
@@ -96,6 +96,7 @@ Copyright @copyright{} 2021 Domagoj Stolfa@*
 Copyright @copyright{} 2021 Hui Lu@*
 Copyright @copyright{} 2021 pukkamustard@*
 Copyright @copyright{} 2021 Alice Brenon@*
+Copyright @copyright{} 2021 Andrew Tropin@*
 
 Permission is granted to copy, distribute and/or modify this document
 under the terms of the GNU Free Documentation License, Version 1.3 or
@@ -167,6 +168,7 @@ Weblate} (@pxref{Translating Guix}).
 * Programming Interface::       Using Guix in Scheme.
 * Utilities::                   Package management commands.
 * System Configuration::        Configuring the operating system.
+* Home Configuration::          Configuring the home environment.
 * Documentation::               Browsing software user manuals.
 * Installing Debugging Files::  Feeding the debugger.
 * Security Updates::            Deploying security fixes quickly.
@@ -328,6 +330,10 @@ System Configuration
 * Running Guix in a VM::        How to run Guix System in a virtual machine.
 * Defining Services::           Adding new service definitions.
 
+Home Environment Configuration
+
+* Invoking guix home::          Instantiating a home environment configuration.
+
 Services
 
 * Base Services::               Essential system services.
@@ -16181,9 +16187,9 @@ This is the type of the @code{mcron} service, whose value is an
 @code{mcron-configuration} object.
 
 This service type can be the target of a service extension that provides
-it additional job specifications (@pxref{Service Composition}).  In
-other words, it is possible to define services that provide additional
-mcron jobs to run.
+additional job specifications (@pxref{Service Composition}).  In other
+words, it is possible to define services that provide additional mcron
+jobs to run.
 @end defvr
 
 @deftp {Data Type} mcron-configuration
@@ -35357,6 +35363,732 @@ system:
 This service represents PID@tie{}1.
 @end defvr
 
+@node Home Configuration
+@chapter Home Configuration
+@cindex home configuration
+Guix supports declarative configuration of @dfn{home environments} by
+utilizing the configuration mechanism described in the previous chapter
+(@pxref{Defining Services}), but for user's dotfiles and packages.  It
+works both on Guix System and foreign distros and allows users to
+declare all the packages and services that should be installed and
+configured for the user.  Once a user has written a file containing
+@code{home-environment} record, such a configuration can be
+@dfn{instantiated} by an unprivileged user with the @command{guix home}
+command (@pxref{Invoking guix home}).
+@c Maybe later, it will be possible to make home configuration a part of
+@c system configuration to make everything managed by guix system.
+
+@quotation Note
+The functionality described in this section is still under development
+and is subject to change.  Get in touch with us on
+@email{guix-devel@@gnu.org}!
+@end quotation
+
+The user's home environment usually consists of three basic parts:
+software, configuration, and state.  Software in mainstream distros are
+usually installed system-wide, but with GNU Guix most software packages
+can be installed on a per-user basis without needing root privileges,
+and are thus considered part of the user’s @dfn{home environment}.
+Packages on their own not very useful in many cases, because often they
+require some additional configuration, usually config files that reside
+in @env{XDG_CONFIG_HOME} (@file{~/.config} by default) or other
+directories.  Everything else can be considered state, like media files,
+application databases, and logs.
+
+Using Guix for managing home environments provides a number of
+advantages:
+
+@itemize
+
+@item All software can be configured in one language (Guile Scheme),
+this gives users the ability to share values between configurations of
+different programs.
+
+@item A well-defined home environment is self-contained and can be
+created in a declarative and reproducible way---there is no need to grab
+external binaries or manually edit some configuration file.
+
+@item After every @command{guix home reconfigure} invocation, a new home
+environment generation will be created.  This means that users can
+rollback to a previous home environment generation so they don’t have to
+worry about breaking their configuration.
+
+@item It is possible to manage stateful data with Guix Home, this
+includes the ability to automatically clone Git repositories on the
+initial setup of the machine, and periodically running commands like
+@command{rsync} to sync data with another host.  This functionality is
+still in an experimental stage, though.
+
+@end itemize
+
+@menu
+* Declaring the Home Environment::  Customizing your Home.
+* Configuring the Shell::     Enabling home environment.
+* Home Services::             Specifying home services.
+* Invoking guix home::        Instantiating a home configuration.
+@end menu
+
+@node Declaring the Home Environment
+@section Declaring the Home Environment
+The home environment is configured by providing a
+@code{home-environment} declaration in a file that can be passed to the
+@command{guix home} command (@pxref{Invoking guix home}).  A simple
+setup can include Bash and a custom text configuration, like in the
+example below.  Don't be afraid to declare home environment parts, which
+overlaps with your current dotfiles, before installing any configuration
+files, Guix Home will back up existing config files to a separate place
+in the home folder.
+
+@quotation Note
+It is highly recommended that you manage your shell or shells with Guix
+Home, because it will make sure that all the necessary scripts are
+sourced by the shell configuration file.  Otherwise you will need to do
+it manually. (@pxref{Configuring the Shell}).
+@end quotation
+
+@findex home-environment
+@lisp
+@include he-config-bare-bones.scm
+@end lisp
+
+The @code{packages} field should be self-explanatory, it will install
+the list of packages into the user's profile.  The most important field
+is @code{services}, it contains a list of @dfn{home services}, which are
+the basic building blocks of a home environment.
+
+There is no daemon (at least not necessarily) related to a home service,
+a home service is just an element that is used to declare part of home
+environment and extend other parts of it.  The extension mechanism
+discussed in the previous chapter (@pxref{Defining Services}) should not
+be confused with @ref{Shepherd Services}.  Using this extension
+mechanism and some Scheme code that glues things together gives the user
+the freedom to declare their own, very custom, home environments.
+
+@node Configuring the Shell
+@section Configuring the Shell
+This section is safe to skip if your shell or shells are managed by
+Guix Home.  Otherwise, read it carefully.
+
+There are a few scripts that must be evaluated by a login shell to
+activate the home environment.  The shell startup files only read by
+login shells often have @code{profile} suffix.  For more information
+about login shells see @ref{Invoking Bash,,, bash, The GNU Bash
+Reference Manual} and see @ref{Bash Startup Files,,, bash, The GNU Bash
+Reference Manual}.
+
+The first script that needs to be sourced is @file{setup-environment},
+which sets all the necessary environment variables (including variables
+declared by the user) and the second one is @file{on-first-login}, which
+starts Shepherd for the current user and performs actions declared by
+other home services that extends
+@code{home-run-on-first-login-service-type}.
+
+Guix Home will always create @file{~/.profile}, which contains the
+following lines:
+
+@example
+HOME_ENVIRONMENT=$HOME/.guix-home
+. $HOME_ENVIRONMENT/setup-environment
+$HOME_ENVIRONMENT/on-first-login
+@end example
+
+This makes POSIX compliant login shells activate the home environment.
+However, in most cases this file won't be read by most modern shells,
+because they are run in non POSIX mode by default and have their own
+@file{*profile} startup files.  For example Bash will prefer
+@file{~/.bash_profile} in case it exists and only if it doesn't will it
+fallback to @file{~/.profile}.  Zsh (if no additional options are
+specified) will ignore @file{~/.profile}, even if @file{~/.zprofile}
+doesn't exist.
+
+To make your shell respect @file{~/.profile}, add @code{. ~/.profile} or
+@code{source ~/profile} to the startup file for the login shell.  In
+case of Bash, it is @file{~/.bash_profile}, and in case of Zsh, it is
+@file{~/.zprofile}.
+
+@quotation Note
+This step is only required if your shell is NOT managed by Guix Home.
+Otherwise, everything will be done automatically.
+@end quotation
+
+@node Home Services
+@section Home Services
+@cindex home services
+
+A @dfn{home service} is not necessarily something that has a daemon and
+is managed by Shepherd (@pxref{Jump Start,,, shepherd, The GNU Shepherd
+Manual}), in most cases it doesn't.  It's a simple building block of the
+home environment, often declaring a set of packages to be installed in
+the home environment profile, a set of config files to be symlinked into
+@env{XDG_CONFIG_HOME} (@file{~/.config} by default), and environment
+variables to be set by a login shell.
+
+There is a service extension mechanism (@pxref{Service Composition})
+which allows home services to extend other home services and utilize
+capabilities they provide; for example: declare mcron jobs
+(@pxref{Top,,, mcron, GNU@tie{}Mcron}) by extending @ref{Mcron Home
+Service}; declare daemons by extending @ref{Shepherd Home Service}; add
+commands, which will be invoked on by the Bash by extending
+@ref{Shells Home Services, @code{home-bash-service-type}}.
+
+A good way to discover avaliable home services is using the
+@command{guix home search} command (@pxref{Invoking guix home}).  After
+the required home services are found, include its module with the
+@code{use-modules} form (@pxref{use-modules,, Using Guile Modules,
+guile, The GNU Guile Reference Manual}), or the @code{#:use-modules}
+directive (@pxref{define-module,, Creating Guile Modules, guile, The GNU
+Guile Reference Manual}) and declare a home service using the
+@code{service} function, or extend a service type by declaring a new
+service with the @code{simple-service} procedure from @code{(gnu
+services)}.
+
+@menu
+* Essential Home Services::  Environment variables, packages, on-* scripts.
+* Shells: Shells Home Services.          POSIX shells, Bash, Zsh.
+* Mcron: Mcron Home Service.             Scheduled User's Job Execution.
+* Shepherd: Shepherd Home Service.       Managing User's Daemons.
+@end menu
+@c In addition to that Home Services can provide
+
+@node Essential Home Services
+@subsection Essential Home Services
+There are a few essential services defined in @code{(gnu
+home-services)}, they are mostly for internal use and are required to
+build a home environment, but some of them will be useful for the end
+user.
+
+@cindex environment variables
+
+@defvr {Scheme Variable} home-environment-variables-service-type
+The service of this type will be instantiated by every home environment
+automatically by default, there is no need to define it, but someone may
+want to extend it with a list of pairs to set some environment
+variables.
+
+@lisp
+(list ("ENV_VAR1" . "value1")
+      ("ENV_VAR2" . "value2"))
+@end lisp
+
+The easiest way to extend a service type, without defining new service
+type is to use the @code{simple-service} helper from @code{(gnu
+services)}.
+
+@lisp
+(simple-service 'some-useful-env-vars-service
+		home-environment-variables-service-type
+		`(("LESSHISTFILE" . "$XDG_CACHE_HOME/.lesshst")
+                  ("SHELL" . ,(file-append zsh "/bin/zsh"))
+                  ("USELESS_VAR" . #f)
+                  ("_JAVA_AWT_WM_NONREPARENTING" . #t)))
+@end lisp
+
+If you include such a service in you home environment definition, it
+will add the following content to the @file{setup-environment} script
+(which is expected to be sourced by the login shell):
+
+@example
+export LESSHISTFILE=$XDG_CACHE_HOME/.lesshst
+export SHELL=/gnu/store/2hsg15n644f0glrcbkb1kqknmmqdar03-zsh-5.8/bin/zsh
+export _JAVA_AWT_WM_NONREPARENTING
+@end example
+
+@quotation Note
+Make sure that module @code{(gnu packages shells)} is imported with
+@code{use-modules} or any other way, this namespace contains the
+definition of the @code{zsh} packages, which is used in the example
+above.
+@end quotation
+
+The association list (@pxref{Association Lists, alists, Association
+Lists, guile, The GNU Guile Reference manual}) is a data structure
+containing key-value pairs, for
+@code{home-environment-variables-service-type} the key is always a
+string, the value can be a string, string-valued gexp
+(@pxref{G-Expressions}), file-like object (@pxref{G-Expressions,
+file-like object}) or boolean.  For gexps, the variable will be set to
+the value of the gexp; for file-like objects, it will be set to the path
+of the file in the store (@pxref{The Store}); for @code{#t}, it will
+export the variable without any value; and for @code{#f}, it will omit
+variable.
+
+@end defvr
+
+@defvr {Scheme Variable} home-profile-service-type
+The service of this type will be instantiated by every home environment
+automatically, there is no need to define it, but you may want to extend
+it with a list of packages if you want to install additional packages
+into your profile.  Other services, which need to make some programs
+avaliable to the user will also extend this service type.
+
+The extension value is just a list of packages:
+
+@lisp
+(list htop vim emacs)
+@end lisp
+
+The same approach as @code{simple-service} (@pxref{Service Reference,
+simple-service}) for @code{home-environment-variables-service-type} can
+be used here, too.  Make sure that modules containing the specified
+packages are imported with @code{use-modules}.  To find a package or
+information about its module use @command{guix search} (@pxref{Invoking
+guix package}).  Alternatively, @code{specification->package} can be
+used to get the package record from string without importing related
+module.
+@end defvr
+
+There are few more essential services, but users are not expected to
+extend them.
+
+@defvr {Scheme Variable} home-service-type
+The root of home services DAG, it generates a folder, which later will be
+symlinked to @file{~/.guix-home}, it contains configurations,
+profile with binaries and libraries, and some necessary scripts to glue
+things together.
+@end defvr
+
+@defvr {Scheme Variable} home-run-on-first-login-service-type
+The service of this type generates a Guile script, which is expected to
+be executed by the login shell.  It is only executed if the special flag
+file inside @env{XDG_RUNTIME_DIR} hasn't been created, this prevents
+redundant executions of the script if multiple login shells are spawned.
+
+It can be extended with a gexp.  However, to autostart an application,
+users @emph{should not} use this service, in most cases it's better to extend
+@code{home-shpeherd-service-type} with a Shepherd service
+(@pxref{Shepherd Services}), or extend the shell's startup file with
+required command using the appropriate service type.
+@end defvr
+
+@defvr {Scheme Variable} home-activation-service-type
+The service of this type generates a guile script, which runs on every
+@command{guix home reconfigure} invocation or any other action, which
+leads to the activation of the home environment.
+@end defvr
+
+@node Shells Home Services
+@subsection Shells
+
+@cindex shell
+@cindex login shell
+@cindex interactive shell
+@cindex bash
+@cindex zsh
+
+Shells play a quite important role in the environment initialization
+process, you can configure them manually as described in section
+@ref{Configuring the Shell}, but the recommended way is to use home services
+listed below.  It's both easier and more reliable.
+
+Each home environment instantiates
+@code{home-shell-profile-service-type}, which creates a
+@file{~/.profile} startup file for all POSIX-compatible shells.  This
+file contains all the necessary steps to properly initialize the
+environment, but many modern shells like Bash or Zsh prefer their own
+startup files, that's why the respective home services
+(@code{home-bash-service-type} and @code{home-zsh-service-type}) ensure
+that @file{~/.profile} is sourced by @file{~/.bash_profile} and
+@file{~/.zprofile}, respectively.
+
+@subsubheading Shell Profile Service
+
+@deftp {Data Type} home-shell-profile-configuration
+Available @code{home-shell-profile-configuration} fields are:
+
+@table @asis
+@item @code{profile} (default: @code{()}) (type: text-config)
+@code{home-shell-profile} is instantiated automatically by
+@code{home-environment}, DO NOT create this service manually, it can
+only be extended.  @code{profile} is a list of strings or gexps, which
+will go to @file{~/.profile}.  By default @file{~/.profile} contains the
+initialization code, which have to be evaluated by login shell to make
+home-environment's profile avaliable to the user, but other commands can
+be added to the file if it is really necessary.  In most cases shell's
+configuration files are preferred places for user's customizations.
+Extend home-shell-profile service only if you really know what you do.
+
+@end table
+
+@end deftp
+
+@subsubheading Bash Home Service
+
+@deftp {Data Type} home-bash-configuration
+Available @code{home-bash-configuration} fields are:
+
+@table @asis
+@item @code{package} (default: @code{bash}) (type: package)
+The Bash package to use.
+
+@item @code{guix-defaults?} (default: @code{#t}) (type: boolean)
+Add sane defaults like reading @file{/etc/bashrc}, coloring output for
+@code{ls} provided by guix to @file{.bashrc}.
+
+@item @code{environment-variables} (default: @code{()}) (type: alist)
+Association list of environment variables to set for the Bash session.
+
+@item @code{bash-profile} (default: @code{()}) (type: text-config)
+List of strings or gexps, which will be added to @file{.bash_profile}.
+Used for executing user's commands at start of login shell (In most
+cases the shell started on tty just after login).  @file{.bash_login}
+won't be ever read, because @file{.bash_profile} always present.
+
+@item @code{bashrc} (default: @code{()}) (type: text-config)
+List of strings or gexps, which will be added to @file{.bashrc}.  Used
+for executing user's commands at start of interactive shell (The shell
+for interactive usage started by typing @code{bash} or by terminal app
+or any other program).
+
+@item @code{bash-logout} (default: @code{()}) (type: text-config)
+List of strings or gexps, which will be added to @file{.bash_logout}.
+Used for executing user's commands at the exit of login shell.  It won't
+be read in some cases (if the shell terminates by exec'ing another
+process for example).
+
+@end table
+
+@end deftp
+
+@subsubheading Zsh Home Service
+
+@deftp {Data Type} home-zsh-configuration
+Available @code{home-zsh-configuration} fields are:
+
+@table @asis
+@item @code{package} (default: @code{zsh}) (type: package)
+The Zsh package to use.
+
+@item @code{xdg-flavor?} (default: @code{#t}) (type: boolean)
+Place all the configs to @file{$XDG_CONFIG_HOME/zsh}.  Makes
+@file{~/.zshenv} to set @env{ZDOTDIR} to @file{$XDG_CONFIG_HOME/zsh}.
+Shell startup process will continue with
+@file{$XDG_CONFIG_HOME/zsh/.zshenv}.
+
+@item @code{environment-variables} (default: @code{()}) (type: alist)
+Association list of environment variables to set for the Zsh session.
+
+@item @code{zshenv} (default: @code{()}) (type: text-config)
+List of strings or gexps, which will be added to @file{.zshenv}.  Used
+for setting user's shell environment variables.  Must not contain
+commands assuming the presence of tty or producing output.  Will be read
+always.  Will be read before any other file in @env{ZDOTDIR}.
+
+@item @code{zprofile} (default: @code{()}) (type: text-config)
+List of strings or gexps, which will be added to @file{.zprofile}.  Used
+for executing user's commands at start of login shell (In most cases the
+shell started on tty just after login).  Will be read before
+@file{.zlogin}.
+
+@item @code{zshrc} (default: @code{()}) (type: text-config)
+List of strings or gexps, which will be added to @file{.zshrc}.  Used
+for executing user's commands at start of interactive shell (The shell
+for interactive usage started by typing @code{zsh} or by terminal app or
+any other program).
+
+@item @code{zlogin} (default: @code{()}) (type: text-config)
+List of strings or gexps, which will be added to @file{.zlogin}.  Used
+for executing user's commands at the end of starting process of login
+shell.
+
+@item @code{zlogout} (default: @code{()}) (type: text-config)
+List of strings or gexps, which will be added to @file{.zlogout}.  Used
+for executing user's commands at the exit of login shell.  It won't be
+read in some cases (if the shell terminates by exec'ing another process
+for example).
+
+@end table
+
+@end deftp
+
+@node Mcron Home Service
+@subsection Scheduled User's Job Execution
+
+@cindex cron
+@cindex mcron
+@cindex scheduling jobs
+
+The @code{(gnu home-services mcron)} module provides an interface to
+GNU@tie{}mcron, a daemon to run jobs at scheduled times (@pxref{Top,,,
+mcron, GNU@tie{}mcron}).  The information about system's mcron is
+applicable here (@pxref{Scheduled Job Execution}), the only difference
+for home services is that they have to be declared in a
+@code{home-envirnoment} record instead of an @code{operating-system}
+record.
+
+@defvr {Scheme Variable} home-mcron-service-type
+This is the type of the @code{mcron} home service, whose value is an
+@code{home-mcron-configuration} object.  It allows to manage scheduled
+tasks.
+
+This service type can be the target of a service extension that provides
+additional job specifications (@pxref{Service Composition}).  In other
+words, it is possible to define services that provide additional mcron
+jobs to run.
+@end defvr
+
+@deftp {Data Type} home-mcron-configuration
+Data type representing the configuration of mcron.
+
+@table @asis
+@item @code{mcron} (default: @var{mcron})
+The mcron package to use.
+
+@item @code{jobs}
+This is a list of gexps (@pxref{G-Expressions}), where each gexp
+corresponds to an mcron job specification (@pxref{Syntax, mcron job
+specifications,, mcron, GNU@tie{}mcron}).
+@end table
+@end deftp
+
+@node Shepherd Home Service
+@subsection Managing User's Daemons
+
+@cindex shepherd services
+
+@defvr {Scheme Variable} home-shepherd-service-type
+The service type for the userland Shepherd, which allows one to manage
+long-running processes or one-shot tasks.  User's Shepherd is not an
+init process (PID 1), but almost all other information described in
+(@pxref{Shepherd Services}) is applicable here too.
+
+This is the service type that extensions target when they want to create
+shepherd services (@pxref{Service Types and Services}, for an example).
+Each extension must pass a list of @code{<shepherd-service>}.  Its
+value must be a @code{shepherd-configuration}, as described below.
+@end defvr
+
+@deftp {Data Type} shepherd-configuration
+This data type represents the Shepherd's configuration.
+
+@table @code
+@item shepherd (default: @code{shepherd})
+The Shepherd package to use.
+
+@item auto-start? (default: @code{#t})
+Whether or not to start Shepherd on first login.
+
+@item services (default: @code{'()})
+A list of @code{<shepherd-service>} to start.
+You should probably use the service extension
+mechanism instead (@pxref{Shepherd Services}).
+@end table
+@end deftp
+
+@node Invoking guix home
+@section Invoking @code{guix home}
+
+Once you have written a home environment declaration (@pxref{Declaring
+the Home Environment,,,,}, it can be @dfn{instantiated} using the
+@command{guix home} command.  The synopsis is:
+
+@example
+guix home @var{options}@dots{} @var{action} @var{file}
+@end example
+
+@var{file} must be the name of a file containing a
+@code{home-environment} declaration.  @var{action} specifies how the
+home environment is instantiated, but there are few auxuliary actions
+which don't instantiate it.  Currently the following values are
+supported:
+
+@table @code
+@item search
+Display available home service type definitions that match the given
+regular expressions, sorted by relevance:
+
+@cindex shell
+@cindex shell-profile
+@cindex bash
+@cindex zsh
+@example
+$ guix home search shell
+name: home-shell-profile
+location: gnu/home-services/shells.scm:73:2
+extends: home-files
+description: Create `~/.profile', which is used for environment initialization
++ of POSIX compatible login shells.  Can be extended with a list of strings or
++ gexps.
+relevance: 6
+
+name: home-zsh-plugin-manager
+location: gnu/home-services/shellutils.scm:28:2
+extends: home-zsh home-profile
+description: Install plugins in profile and configure Zsh to load them.
+relevance: 1
+
+name: home-zsh-direnv
+location: gnu/home-services/shellutils.scm:69:2
+extends: home-profile home-zsh
+description: Enables `direnv' for `zsh'.  Adds hook to `.zshrc' and installs a
++ package in the profile.
+relevance: 1
+
+name: home-zsh-autosuggestions
+location: gnu/home-services/shellutils.scm:43:2
+extends: home-zsh-plugin-manager home-zsh
+description: Enables Fish-like fast/unobtrusive autosuggestions for `zsh' and
++ sets reasonable default values for some plugin's variables to improve perfomance
++ and adjust behavior: `(history completion)' is set for strategy, manual rebind
++ and async are enabled.
+relevance: 1
+
+name: home-zsh
+location: gnu/home-services/shells.scm:236:2
+extends: home-files home-profile
+description: Install and configure Zsh.
+relevance: 1
+
+name: home-bash
+location: gnu/home-services/shells.scm:388:2
+extends: home-files home-profile
+description: Install and configure Bash.
+relevance: 1
+
+@dots{}
+@end example
+
+As for @command{guix package --search}, the result is written in
+@code{recutils} format, which makes it easy to filter the output
+(@pxref{Top, GNU recutils databases,, recutils, GNU recutils manual}).
+
+@item reconfigure
+Build the home environment described in @var{file}, and switch to it.
+Switching means that the activation script will be evaluated and (in
+basic scenario) symlinks to configuration files generated from
+@code{home-environment} declaration will be created in @file{~}.  If the
+file with the same path already exists in home folder it will be moved
+to @file{~/TIMESTAMP-guix-home-legacy-configs-backup}, where TIMESTAMP
+is a current UNIX epoch time.
+
+@quotation Note
+It is highly recommended to run @command{guix pull} once before you run
+@command{guix home reconfigure} for the first time (@pxref{Invoking guix
+pull}).
+@end quotation
+
+This effects all the configuration specified in @var{file}.  The command
+starts Shepherd services specified in @var{file} that are not currently
+running; if a service is currently running, this command will arrange
+for it to be upgraded the next time it is stopped (e.g.@: by @code{herd
+stop X} or @code{herd restart X}).
+
+This command creates a new generation whose number is one greater than
+the current generation (as reported by @command{guix home
+list-generations}).  If that generation already exists, it will be
+overwritten.  This behavior mirrors that of @command{guix package}
+(@pxref{Invoking guix package}).
+
+@cindex provenance tracking, of the home environment
+Upon completion, the new home is deployed under @file{~/.guix-home}.
+This directory contains @dfn{provenance meta-data}: the list of channels
+in use (@pxref{Channels}) and @var{file} itself, when available.  You
+can view the provenance information by running:
+
+@example
+guix home describe
+@end example
+
+This information is useful should you later want to inspect how this
+particular generation was built.  In fact, assuming @var{file} is
+self-contained, you can later rebuild generation @var{n} of your
+home environment with:
+
+@example
+guix time-machine \
+  -C /var/guix/profiles/per-user/@var{USER}/guix-home-@var{n}-link/channels.scm -- \
+  home reconfigure \
+  /var/guix/profiles/per-user/@var{USER}/guix-home-@var{n}-link/configuration.scm
+
+@end example
+
+You can think of it as some sort of built-in version control!  Your
+home is not just a binary artifact: @emph{it carries its own source}.
+@c @xref{Service Reference, @code{provenance-service-type}}, for more
+@c information on provenance tracking.
+
+@c @footnote{This action (and the related actions
+@c @code{switch-generation} and @code{roll-back}) are usable after the
+@c home environment is initialized.}.
+
+@item switch-generation
+@cindex home generations
+Switch to an existing home generation.  This action atomically switches
+the home profile to the specified home generation.
+
+The target generation can be specified explicitly by its generation
+number.  For example, the following invocation would switch to home
+generation 7:
+
+@example
+guix home switch-generation 7
+@end example
+
+The target generation can also be specified relative to the current
+generation with the form @code{+N} or @code{-N}, where @code{+3} means
+``3 generations ahead of the current generation,'' and @code{-1} means
+``1 generation prior to the current generation.''  When specifying a
+negative value such as @code{-1}, you must precede it with @code{--} to
+prevent it from being parsed as an option.  For example:
+
+@example
+guix home switch-generation -- -1
+@end example
+
+This action will fail if the specified generation does not exist.
+
+@item roll-back
+@cindex rolling back
+Switch to the preceding home generation.  This is the inverse
+of @command{reconfigure}, and it is exactly the same as invoking
+@command{switch-generation} with an argument of @code{-1}.
+
+@item delete-generations
+@cindex deleting home generations
+@cindex saving space
+Delete home generations, making them candidates for garbage collection
+(@pxref{Invoking guix gc}, for information on how to run the ``garbage
+collector'').
+
+This works in the same way as @samp{guix package --delete-generations}
+(@pxref{Invoking guix package, @option{--delete-generations}}).  With no
+arguments, all home generations but the current one are deleted:
+
+@example
+guix home delete-generations
+@end example
+
+You can also select the generations you want to delete.  The example below
+deletes all the home generations that are more than two month old:
+
+@example
+guix home delete-generations 2m
+@end example
+
+@item build
+Build the derivation of the home environment, which includes all the
+configuration files and programs needed.  This action does not actually
+install anything.
+
+@item describe
+Describe the current home generation: its file name, as well as
+provenance information when available.
+
+@item list-generations
+List a summary of each generation of the home environment available on
+disk, in a human-readable way.  This is similar to the
+@option{--list-generations} option of @command{guix package}
+(@pxref{Invoking guix package}).
+
+Optionally, one can specify a pattern, with the same syntax that is used
+in @command{guix package --list-generations}, to restrict the list of
+generations displayed.  For instance, the following command displays
+generations that are up to 10 days old:
+
+@example
+$ guix home list-generations 10d
+@end example
+
+@end table
 
 @node Documentation
 @chapter Documentation
diff --git a/doc/he-config-bare-bones.scm b/doc/he-config-bare-bones.scm
new file mode 100644
index 0000000000..01be46a7b0
--- /dev/null
+++ b/doc/he-config-bare-bones.scm
@@ -0,0 +1,24 @@
+(use-modules (gnu home)
+             (gnu home-services)
+             (gnu home-services shells)
+             (gnu services)
+             (gnu packages admin)
+             (guix gexp))
+
+
+(home-environment
+ (packages (list htop))
+ (services
+  (list
+   (service home-bash-service-type
+            (home-bash-configuration
+             (guix-defaults? #t)
+             (bash-profile '("\
+export HISTFILE=$XDG_CACHE_HOME/.bash_history"))))
+
+   (simple-service 'test-config
+                   home-files-service-type
+                   (list `("config/test.conf"
+                           ,(plain-file "tmp-file.txt"
+                                        "the content of ~/.config/test.conf")))))))
+
diff --git a/etc/news.scm b/etc/news.scm
index 63d832a610..dc45aaf496 100644
--- a/etc/news.scm
+++ b/etc/news.scm
@@ -15,6 +15,7 @@
 ;; Copyright © 2021 Chris Marusich <cmmarusich@gmail.com>
 ;; Copyright © 2021 Maxime Devos <maximedevos@telenet.be>
 ;; Copyright © 2021 Xinglu Chen <public@yoctocell.xyz>
+;; Copyright © 2021 Andrew Tropin <andrew@trop.in>
 ;;
 ;; Copying and distribution of this file, with or without modification, are
 ;; permitted in any medium without royalty provided the copyright notice and
@@ -22,6 +23,35 @@
 
 (channel-news
  (version 0)
+(entry (commit "a2324d8b56eabf8117bca220a507cc791edffd2e")
+        (title
+         (en "Guix Home is a part of GNU Guix")
+         (ru "Guix Home теперь поставляется в составе GNU Guix"))
+        (body
+         (en "Guix Home splitted out from rde project and now is a part of
+Guix proper.  The new @command{guix home} with its actions allows users to
+manage their packages and configurations (aka. dotfiles) in a declarative way,
+similar to how many people manage their system with @command{guix system}.
+
+Take a look at available actions and arguments:
+@example
+guix home --help
+@end example
+
+See @command{info \"(guix) Home Configuration\"} for more information.")
+         (ru "Guix Home отделился от проекта rde и теперь является частью
+Guix.  Новая команда @command{guix home} даёт возможность пользователям
+управлять их пакетами и конфигурациями (дотфайлами) для них в декларативном
+стиле, аналогично тому, как многие люди управляют своими системами с помощью
+@command{guix system}.
+
+Чтобы получить список доступных действий и аргументов:
+@example
+guix home --help
+@end example
+
+Смотрите @command{info \"(guix) Home Configuration\"} для получения более
+детальных сведений.")))
 
  (entry (commit "5b32ad4f6f555d305659cee825879df075b06331")
         (title
diff --git a/gnu/home-services.scm b/gnu/home-services.scm
new file mode 100644
index 0000000000..9f1e986616
--- /dev/null
+++ b/gnu/home-services.scm
@@ -0,0 +1,524 @@
+;;; GNU Guix --- Functional package management for GNU
+;;; Copyright © 2021 Andrew Tropin <andrew@trop.in>
+;;; Copyright © 2021 Xinglu Chen <public@yoctocell.xyz>
+;;;
+;;; This file is part of GNU Guix.
+;;;
+;;; GNU Guix is free software; you can redistribute it and/or modify it
+;;; under the terms of the GNU General Public License as published by
+;;; the Free Software Foundation; either version 3 of the License, or (at
+;;; your option) any later version.
+;;;
+;;; GNU Guix is distributed in the hope that it will be useful, but
+;;; WITHOUT ANY WARRANTY; without even the implied warranty of
+;;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+;;; GNU General Public License for more details.
+;;;
+;;; You should have received a copy of the GNU General Public License
+;;; along with GNU Guix.  If not, see <http://www.gnu.org/licenses/>.
+
+(define-module (gnu home-services)
+  #:use-module (gnu services)
+  #:use-module (guix channels)
+  #:use-module (guix monads)
+  #:use-module (guix store)
+  #:use-module (guix gexp)
+  #:use-module (guix profiles)
+  #:use-module (guix sets)
+  #:use-module (guix ui)
+  #:use-module (guix discovery)
+  #:use-module (guix diagnostics)
+
+  #:use-module (srfi srfi-1)
+  #:use-module (ice-9 match)
+
+  #:export (home-service-type
+            home-profile-service-type
+            home-environment-variables-service-type
+            home-files-service-type
+            home-run-on-first-login-service-type
+            home-activation-service-type
+            home-run-on-change-service-type
+            home-provenance-service-type
+
+            fold-home-service-types)
+
+  #:re-export (service
+               service-type
+               service-extension))
+
+;;; Comment:
+;;;
+;;; This module is similar to (gnu system services) module, but
+;;; provides Home Services, which are supposed to be used for building
+;;; home-environment.
+;;;
+;;; Home Services use the same extension as System Services.  Consult
+;;; (gnu system services) module or manual for more information.
+;;;
+;;; home-service-type is a root of home services DAG.
+;;;
+;;; home-profile-service-type is almost the same as profile-service-type, at least
+;;; for now.
+;;;
+;;; home-environment-variables-service-type generates a @file{setup-environment}
+;;; shell script, which is expected to be sourced by login shell or other program,
+;;; which starts early and spawns all other processes.  Home services for shells
+;;; automatically add code for sourcing this file, if person do not use those home
+;;; services they have to source this script manually in their's shell *profile
+;;; file (details described in the manual).
+;;;
+;;; home-files-service-type is similar to etc-service-type, but doesn't extend
+;;; home-activation, because deploy mechanism for config files is pluggable and
+;;; can be different for different home environments: The default one is called
+;;; symlink-manager (will be introudced in a separate patch series), which creates
+;;; links for various dotfiles (like $XDG_CONFIG_HOME/$APP/...) to store, but is
+;;; possible to implement alternative approaches like read-only home from Julien's
+;;; guix-home-manager.
+;;;
+;;; home-run-on-first-login-service-type provides an @file{on-first-login} guile
+;;; script, which runs provided gexps once, when user makes first login.  It can
+;;; be used to start user's Shepherd and maybe some other process.  It relies on
+;;; assumption that /run/user/$UID will be created on login by some login
+;;; manager (elogind for example).
+;;;
+;;; home-activation-service-type provides an @file{activate} guile script, which
+;;; do three main things:
+;;;
+;;; - Sets environment variables to the values declared in
+;;; @file{setup-environment} shell script.  It's necessary, because user can set
+;;; for example XDG_CONFIG_HOME and it should be respected by activation gexp of
+;;; symlink-manager.
+;;;
+;;; - Sets GUIX_NEW_HOME and possibly GUIX_OLD_HOME vars to paths in the store.
+;;; Later those variables can be used by activation gexps, for example by
+;;; symlink-manager or run-on-change services.
+;;;
+;;; - Run all activation gexps provided by other home services.
+;;;
+;;; home-run-on-change-service-type allows to trigger actions during
+;;; activation if file or directory specified by pattern is changed.
+;;;
+;;; Code:
+
+
+(define (home-derivation entries mextensions)
+  "Return as a monadic value the derivation of the 'home'
+directory containing the given entries."
+  (mlet %store-monad ((extensions (mapm/accumulate-builds identity
+                                                          mextensions)))
+    (lower-object
+     (file-union "home" (append entries (concatenate extensions))))))
+
+(define home-service-type
+  ;; This is the ultimate service type, the root of the home service
+  ;; DAG.  The service of this type is extended by monadic name/item
+  ;; pairs.  These items end up in the "home-environment directory" as
+  ;; returned by 'home-environment-derivation'.
+  (service-type (name 'home)
+                (extensions '())
+                (compose identity)
+                (extend home-derivation)
+                (default-value '())
+                (description
+                 "Build the home environment top-level directory,
+which in turn refers to everything the home environment needs: its
+packages, configuration files, activation script, and so on.")))
+
+(define (packages->profile-entry packages)
+  "Return a system entry for the profile containing PACKAGES."
+  ;; XXX: 'mlet' is needed here for one reason: to get the proper
+  ;; '%current-target' and '%current-target-system' bindings when
+  ;; 'packages->manifest' is called, and thus when the 'package-inputs'
+  ;; etc. procedures are called on PACKAGES.  That way, conditionals in those
+  ;; inputs see the "correct" value of these two parameters.  See
+  ;; <https://issues.guix.gnu.org/44952>.
+  (mlet %store-monad ((_ (current-target-system)))
+    (return `(("profile" ,(profile
+                           (content (packages->manifest
+                                     (map identity
+                                     ;;(options->transformation transformations)
+                                     (delete-duplicates packages eq?))))))))))
+
+;; MAYBE: Add a list of transformations for packages.  It's better to
+;; place it in home-profile-service-type to affect all profile
+;; packages and prevent conflicts, when other packages relies on
+;; non-transformed version of package.
+(define home-profile-service-type
+  (service-type (name 'home-profile)
+                (extensions
+                 (list (service-extension home-service-type
+                                          packages->profile-entry)))
+                (compose concatenate)
+                (extend append)
+                (description
+                 "This is the @dfn{home profile} and can be found in
+@file{~/.guix-home/profile}.  It contains packages and
+configuration files that the user has declared in their
+@code{home-environment} record.")))
+
+(define (environment-variables->setup-environment-script vars)
+  "Return a file that can be sourced by a POSIX compliant shell which
+initializes the environment.  The file will source the home
+environment profile, set some default environment variables, and set
+environment variables provided in @code{vars}.  @code{vars} is a list
+of pairs (@code{(key . value)}), @code{key} is a string and
+@code{value} is a string or gexp.
+
+If value is @code{#f} variable will be omitted.
+If value is @code{#t} variable will be just exported.
+For any other, value variable will be set to the @code{value} and
+exported."
+  (define (warn-about-duplicate-defenitions)
+    (fold
+     (lambda (x acc)
+       (when (equal? (car x) (car acc))
+         (warning
+          (G_ "duplicate definition for `~a' environment variable ~%") (car x)))
+       x)
+     (cons "" "")
+     (sort vars (lambda (a b)
+                  (string<? (car a) (car b))))))
+
+  (warn-about-duplicate-defenitions)
+  (with-monad
+   %store-monad
+   (return
+    `(("setup-environment"
+       ;; TODO: It's necessary to source ~/.guix-profile too
+       ;; on foreign distros
+       ,(apply mixed-text-file "setup-environment"
+               "\
+HOME_ENVIRONMENT=$HOME/.guix-home
+GUIX_PROFILE=\"$HOME_ENVIRONMENT/profile\"
+PROFILE_FILE=\"$HOME_ENVIRONMENT/profile/etc/profile\"
+[ -f $PROFILE_FILE ] && . $PROFILE_FILE
+
+case $XDG_DATA_DIRS in
+  *$HOME_ENVIRONMENT/profile/share*) ;;
+  *) export XDG_DATA_DIRS=$HOME_ENVIRONMENT/profile/share:$XDG_DATA_DIRS ;;
+esac
+case $MANPATH in
+  *$HOME_ENVIRONMENT/profile/share/man*) ;;
+  *) export MANPATH=$HOME_ENVIRONMENT/profile/share/man:$MANPATH
+esac
+case $INFOPATH in
+  *$HOME_ENVIRONMENT/profile/share/info*) ;;
+  *) export INFOPATH=$HOME_ENVIRONMENT/profile/share/info:$INFOPATH ;;
+esac
+case $XDG_CONFIG_DIRS in
+  *$HOME_ENVIRONMENT/profile/etc/xdg*) ;;
+  *) export XDG_CONFIG_DIRS=$HOME_ENVIRONMENT/profile/etc/xdg:$XDG_CONFIG_DIRS ;;
+esac
+case $XCURSOR_PATH in
+  *$HOME_ENVIRONMENT/profile/share/icons*) ;;
+  *) export XCURSOR_PATH=$HOME_ENVIRONMENT/profile/share/icons:$XCURSOR_PATH ;;
+esac
+
+"
+
+               (append-map
+                (match-lambda
+                  ((key . #f)
+                   '())
+                  ((key . #t)
+                   (list "export " key "\n"))
+                  ((key . value)
+                   (list "export " key "=" value "\n")))
+                vars)))))))
+
+(define home-environment-variables-service-type
+  (service-type (name 'home-environment-variables)
+                (extensions
+                 (list (service-extension
+                        home-service-type
+                        environment-variables->setup-environment-script)))
+                (compose concatenate)
+                (extend append)
+                (default-value '())
+                (description "Set the environment variables.")))
+
+(define (files->files-directory files)
+  "Return a @code{files} directory that contains FILES."
+  (define (assert-no-duplicates files)
+    (let loop ((files files)
+               (seen (set)))
+      (match files
+        (() #t)
+        (((file _) rest ...)
+         (when (set-contains? seen file)
+           (raise (formatted-message (G_ "duplicate '~a' entry for files/")
+                                     file)))
+         (loop rest (set-insert file seen))))))
+
+  ;; Detect duplicates early instead of letting them through, eventually
+  ;; leading to a build failure of "files.drv".
+  (assert-no-duplicates files)
+
+  (file-union "files" files))
+
+(define (files-entry files)
+  "Return an entry for the @file{~/.guix-home/files}
+directory containing FILES."
+  (with-monad %store-monad
+    (return `(("files" ,(files->files-directory files))))))
+
+(define home-files-service-type
+  (service-type (name 'home-files)
+                (extensions
+                 (list (service-extension home-service-type
+                                          files-entry)))
+                (compose concatenate)
+                (extend append)
+                (default-value '())
+                (description "Configuration files for programs that
+will be put in @file{~/.guix-home/files}.")))
+
+(define (compute-on-first-login-script _ gexps)
+  (gexp->script
+   "on-first-login"
+   #~(let* ((xdg-runtime-dir (or (getenv "XDG_RUNTIME_DIR")
+                                 (format #f "/run/user/~a" (getuid))))
+            (flag-file-path (string-append
+                             xdg-runtime-dir "/on-first-login-executed"))
+            (touch (lambda (file-name)
+                     (call-with-output-file file-name (const #t)))))
+       ;; XDG_RUNTIME_DIR dissapears on logout, that means such trick
+       ;; allows to launch on-first-login script on first login only
+       ;; after complete logout/reboot.
+       (when (not (file-exists? flag-file-path))
+         (begin #$@gexps (touch flag-file-path))))))
+
+(define (on-first-login-script-entry m-on-first-login)
+  "Return, as a monadic value, an entry for the on-first-login script
+in the home environment directory."
+  (mlet %store-monad ((on-first-login m-on-first-login))
+        (return `(("on-first-login" ,on-first-login)))))
+
+(define home-run-on-first-login-service-type
+  (service-type (name 'home-run-on-first-login)
+                (extensions
+                 (list (service-extension
+                        home-service-type
+                        on-first-login-script-entry)))
+                (compose identity)
+                (extend compute-on-first-login-script)
+                (default-value #f)
+                (description "Run gexps on first user login.  Can be
+extended with one gexp.")))
+
+
+(define (compute-activation-script init-gexp gexps)
+  (gexp->script
+   "activate"
+   #~(let* ((he-init-file (lambda (he) (string-append he "/setup-environment")))
+            (he-path (string-append (getenv "HOME") "/.guix-home"))
+            (new-home-env (getenv "GUIX_NEW_HOME"))
+            (new-home (or new-home-env
+                          ;; Path of the activation file if called interactively
+                          (dirname (car (command-line)))))
+            (old-home-env (getenv "GUIX_OLD_HOME"))
+            (old-home (or old-home-env
+                          (if (file-exists? (he-init-file he-path))
+                              (readlink he-path)
+                              #f))))
+       (if (file-exists? (he-init-file new-home))
+           (let* ((port   ((@ (ice-9 popen) open-input-pipe)
+                           (format #f "source ~a && env -0"
+                                   (he-init-file new-home))))
+                  (result ((@ (ice-9 rdelim) read-delimited) "" port))
+                  (vars (map (lambda (x)
+                               (let ((si (string-index x #\=)))
+                                 (cons (string-take x si)
+                                       (string-drop x (1+ si)))))
+                             ((@ (srfi srfi-1) remove)
+                              string-null?
+                              (string-split result #\nul)))))
+             (close-port port)
+             (map (lambda (x) (setenv (car x) (cdr x))) vars)
+
+             (setenv "GUIX_NEW_HOME" new-home)
+             (setenv "GUIX_OLD_HOME" old-home)
+
+             #$@gexps
+
+             ;; Do not unset env variable if it was set outside.
+             (unless new-home-env (setenv "GUIX_NEW_HOME" #f))
+             (unless old-home-env (setenv "GUIX_OLD_HOME" #f)))
+           (format #t "\
+Activation script was either called or loaded by file from this direcotry:
+~a
+It doesn't seem that home environment is somewhere around.
+Make sure that you call ./activate by symlink from -home store item.\n"
+                   new-home)))))
+
+(define (activation-script-entry m-activation)
+  "Return, as a monadic value, an entry for the activation script
+in the home environment directory."
+  (mlet %store-monad ((activation m-activation))
+    (return `(("activate" ,activation)))))
+
+(define home-activation-service-type
+  (service-type (name 'home-activation)
+                (extensions
+                 (list (service-extension
+                        home-service-type
+                        activation-script-entry)))
+                (compose identity)
+                (extend compute-activation-script)
+                (default-value #f)
+                (description "Run gexps to activate the current
+generation of home environment and update the state of the home
+directory.  @command{activate} script automatically called during
+reconfiguration or generation switching.  This service can be extended
+with one gexp, but many times, and all gexps must be idempotent.")))
+
+
+;;;
+;;; On-change.
+;;;
+
+(define (compute-on-change-gexp eval-gexps? pattern-gexp-tuples)
+  #~(begin
+      (define (equal-regulars? file1 file2)
+        "Check if FILE1 and FILE2 are bit for bit identical."
+        (let* ((cmp-binary #$(file-append
+                              (@ (gnu packages base) diffutils) "/bin/cmp"))
+               (stats1     (lstat file1))
+               (stats2     (lstat file2)))
+          (cond
+           ((= (stat:ino stats1) (stat:ino stats2))         #t)
+           ((not (= (stat:size stats1) (stat:size stats2))) #f)
+
+           (else (= (system* cmp-binary file1 file2) 0)))))
+
+      (define (equal-symlinks? symlink1 symlink2)
+        "Check if SYMLINK1 and SYMLINK2 are pointing to the same target."
+        (string=? (readlink symlink1) (readlink symlink2)))
+
+      (define (equal-directories? dir1 dir2)
+        "Check if DIR1 and DIR2 have the same content."
+        (define (ordinary-file file)
+          (not (or (string=? file ".")
+                   (string=? file ".."))))
+        (let* ((files1 (scandir dir1 ordinary-file))
+               (files2 (scandir dir2 ordinary-file)))
+          (if (equal? files1 files2)
+              (map (lambda (file)
+                     (equal-files?
+                      (string-append dir1 "/" file)
+                      (string-append dir2 "/" file)))
+                   files1)
+              #f)))
+
+      (define (equal-files? file1 file2)
+        "Compares files, symlinks or directories of the same type."
+        (case (file-type file1)
+          ((directory) (equal-directories? file1 file2))
+          ((symlink) (equal-symlinks? file1 file2))
+          ((regular) (equal-regulars? file1 file2))
+          (else
+           (display "The file type is unsupported by on-change service.\n")
+           #f)))
+
+      (define (file-type file)
+        (stat:type (lstat file)))
+
+      (define (something-changed? file1 file2)
+        (cond
+         ((and (not (file-exists? file1))
+               (not (file-exists? file2))) #f)
+         ((or  (not (file-exists? file1))
+               (not (file-exists? file2))) #t)
+
+         ((not (eq? (file-type file1) (file-type file2))) #t)
+
+         (else
+          (not (equal-files? file1 file2)))))
+
+      (define expressions-to-eval
+        (map
+         (lambda (x)
+           (let* ((file1 (string-append
+                          (or (getenv "GUIX_OLD_HOME")
+                              "/gnu/store/non-existing-generation")
+                          "/" (car x)))
+                  (file2 (string-append (getenv "GUIX_NEW_HOME") "/" (car x)))
+                  (_ (format #t "Comparing ~a and\n~10t~a..." file1 file2))
+                  (any-changes? (something-changed? file1 file2))
+                  (_ (format #t " done (~a)\n"
+                             (if any-changes? "changed" "same"))))
+             (if any-changes? (cadr x) "")))
+         '#$pattern-gexp-tuples))
+
+      (if #$eval-gexps?
+          (begin
+            (display "Evaling on-change gexps.\n\n")
+            (for-each primitive-eval expressions-to-eval)
+            (display "On-change gexps evaluation finished.\n\n"))
+          (display "\
+On-change gexps won't be evaluated, disabled by service
+configuration.\n"))))
+
+(define home-run-on-change-service-type
+  (service-type (name 'home-run-on-change)
+                (extensions
+                 (list (service-extension
+                        home-activation-service-type
+                        identity)))
+                (compose concatenate)
+                (extend compute-on-change-gexp)
+                (default-value #t)
+                (description "\
+G-expressions to run if the specified files have changed since the
+last generation.  The extension should be a list of lists where the
+first element is the pattern for file or directory that expected to be
+changed, and the second element is the G-expression to be evaluated.")))
+
+
+;;;
+;;; Provenance tracking.
+;;;
+
+(define home-provenance-service-type
+  (service-type
+   (name 'home-provenance)
+   (extensions
+    (list (service-extension
+           home-service-type
+           (service-extension-compute
+            (first (service-type-extensions provenance-service-type))))))
+   (default-value #f)                ;the HE config file
+   (description "\
+Store provenance information about the home environment in the home
+environment itself: the channels used when building the home
+environment, and its configuration file, when available.")))
+
+(define sexp->home-provenance sexp->system-provenance)
+(define home-provenance system-provenance)
+
+
+;;;
+;;; Searching
+;;;
+
+(define (parent-directory directory)
+  "Get the parent directory of DIRECTORY"
+  (string-join (drop-right (string-split directory #\/) 1) "/"))
+
+(define %guix-home-root-directory
+  ;; Absolute file name of the module hierarchy.
+  (parent-directory (dirname (search-path %load-path "gnu/home-services.scm"))))
+
+(define %service-type-path
+  ;; Search path for service types.
+  (make-parameter `((,%guix-home-root-directory . "gnu/home-services"))))
+
+(define (all-home-service-modules)
+  "Return the default set of home-service modules."
+  (cons (resolve-interface '(gnu home-services))
+        (all-modules (%service-type-path)
+                     #:warn warn-about-load-error)))
+
+(define* (fold-home-service-types proc seed)
+  (fold-service-types proc seed (all-home-service-modules)))
diff --git a/gnu/home-services/configuration.scm b/gnu/home-services/configuration.scm
new file mode 100644
index 0000000000..3698006c37
--- /dev/null
+++ b/gnu/home-services/configuration.scm
@@ -0,0 +1,107 @@
+;;; GNU Guix --- Functional package management for GNU
+;;; Copyright © 2021 Andrew Tropin <andrew@trop.in>
+;;; Copyright © 2021 Xinglu Chen <public@yoctocell.xyz>
+;;;
+;;; This file is part of GNU Guix.
+;;;
+;;; GNU Guix is free software; you can redistribute it and/or modify it
+;;; under the terms of the GNU General Public License as published by
+;;; the Free Software Foundation; either version 3 of the License, or (at
+;;; your option) any later version.
+;;;
+;;; GNU Guix is distributed in the hope that it will be useful, but
+;;; WITHOUT ANY WARRANTY; without even the implied warranty of
+;;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+;;; GNU General Public License for more details.
+;;;
+;;; You should have received a copy of the GNU General Public License
+;;; along with GNU Guix.  If not, see <http://www.gnu.org/licenses/>.
+
+(define-module (gnu home-services configuration)
+  #:use-module (gnu services configuration)
+  #:use-module (guix gexp)
+  #:use-module (srfi srfi-1)
+  #:use-module (ice-9 curried-definitions)
+  #:use-module (ice-9 match)
+
+  #:export (filter-configuration-fields
+
+            interpose
+            list-of
+
+            list-of-strings?
+            alist?
+            string-or-gexp?
+	    serialize-string-or-gexp
+	    text-config?
+            serialize-text-config
+            generic-serialize-alist-entry
+            generic-serialize-alist))
+
+(define* (filter-configuration-fields configuration-fields fields
+				      #:optional negate?)
+  "Retrieve the fields listed in FIELDS from CONFIGURATION-FIELDS.
+If NEGATE? is @code{#t}, retrieve all fields except FIELDS."
+  (filter (lambda (field)
+            (let ((member? (member (configuration-field-name field) fields)))
+              (if (not negate?) member? (not member?))))
+          configuration-fields))
+
+
+(define* (interpose ls  #:optional (delimiter "\n") (grammar 'infix))
+  "Same as @code{string-join}, but without join and string, returns an
+DELIMITER interposed LS.  Support 'infix and 'suffix GRAMMAR values."
+  (when (not (member grammar '(infix suffix)))
+    (raise
+     (formatted-message
+      (G_ "The GRAMMAR value must be 'infix or 'suffix, but ~a provided.")
+      grammar)))
+  (fold-right (lambda (e acc)
+		(cons e
+		      (if (and (null? acc) (eq? grammar 'infix))
+			  acc
+			  (cons delimiter acc))))
+	      '() ls))
+
+(define (list-of pred?)
+  "Return a procedure that takes a list and check if all the elements of
+the list result in @code{#t} when applying PRED? on them."
+    (lambda (x)
+      (if (list? x)
+          (every pred? x)
+          #f)))
+
+
+(define list-of-strings?
+  (list-of string?))
+
+(define alist? list?)
+
+(define (string-or-gexp? sg) (or (string? sg) (gexp? sg)))
+(define (serialize-string-or-gexp field-name val) "")
+
+(define (text-config? config)
+  (and (list? config) (every string-or-gexp? config)))
+(define (serialize-text-config field-name val)
+  #~(string-append #$@(interpose val "\n" 'suffix)))
+
+(define ((generic-serialize-alist-entry serialize-field) entry)
+  "Apply the SERIALIZE-FIELD procedure on the field and value of ENTRY."
+  (match entry
+    ((field . val) (serialize-field field val))))
+
+(define (generic-serialize-alist combine serialize-field fields)
+  "Generate a configuration from an association list FIELDS.
+
+SERIALIZE-FIELD is a procedure that takes two arguments, it will be
+applied on the fields and values of FIELDS using the
+@code{generic-serialize-alist-entry} procedure.
+
+COMBINE is a procedure that takes one or more arguments and combines
+all the alist entries into one value, @code{string-append} or
+@code{append} are usually good candidates for this.
+
+See the @code{serialize-alist} procedure in `@code{(gnu home-services
+version-control}' for an example usage.)}"
+  (apply combine
+         (map (generic-serialize-alist-entry serialize-field) fields)))
diff --git a/gnu/home-services/fontutils.scm b/gnu/home-services/fontutils.scm
new file mode 100644
index 0000000000..28bfc3d3f7
--- /dev/null
+++ b/gnu/home-services/fontutils.scm
@@ -0,0 +1,65 @@
+;;; GNU Guix --- Functional package management for GNU
+;;; Copyright © 2021 Andrew Tropin <andrew@trop.in>
+;;; Copyright © 2021 Xinglu Chen <public@yoctocell.xyz>
+;;;
+;;; This file is part of GNU Guix.
+;;;
+;;; GNU Guix is free software; you can redistribute it and/or modify it
+;;; under the terms of the GNU General Public License as published by
+;;; the Free Software Foundation; either version 3 of the License, or (at
+;;; your option) any later version.
+;;;
+;;; GNU Guix is distributed in the hope that it will be useful, but
+;;; WITHOUT ANY WARRANTY; without even the implied warranty of
+;;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+;;; GNU General Public License for more details.
+;;;
+;;; You should have received a copy of the GNU General Public License
+;;; along with GNU Guix.  If not, see <http://www.gnu.org/licenses/>.
+
+(define-module (gnu home-services fontutils)
+  #:use-module (gnu home-services)
+  #:use-module (gnu packages fontutils)
+  #:use-module (guix gexp)
+
+  #:export (home-fontconfig-service-type))
+
+;;; Commentary:
+;;;
+;;; Services related to fonts.  home-fontconfig service provides
+;;; fontconfig configuration, which allows fc-* utilities to find
+;;; fonts in Guix Home's profile and regenerates font cache on
+;;; activation.
+;;;
+;;; Code:
+
+(define (add-fontconfig-config-file he-symlink-path)
+  `(("config/fontconfig/fonts.conf"
+     ,(mixed-text-file
+       "fonts.conf"
+       "<?xml version='1.0'?>
+<!DOCTYPE fontconfig SYSTEM 'fonts.dtd'>
+<fontconfig>
+  <dir>~/.guix-home/profile/share/fonts</dir>
+</fontconfig>"))))
+
+(define (regenerate-font-cache-gexp _)
+  `(("profile/share/fonts"
+     ,#~(system* #$(file-append fontconfig "/bin/fc-cache") "-fv"))))
+
+(define home-fontconfig-service-type
+  (service-type (name 'home-fontconfig)
+                (extensions
+                 (list (service-extension
+                        home-files-service-type
+                        add-fontconfig-config-file)
+                       (service-extension
+                        home-run-on-change-service-type
+                        regenerate-font-cache-gexp)
+                       (service-extension
+                        home-profile-service-type
+                        (const (list fontconfig)))))
+                (default-value #f)
+                (description
+                 "Provides configuration file for fontconfig and make
+fc-* utilities aware of font packages installed in Guix Home's profile.")))
diff --git a/gnu/home-services/mcron.scm b/gnu/home-services/mcron.scm
new file mode 100644
index 0000000000..fdfde179a5
--- /dev/null
+++ b/gnu/home-services/mcron.scm
@@ -0,0 +1,115 @@
+;;; GNU Guix --- Functional package management for GNU
+;;; Copyright © 2021 Andrew Tropin <andrew@trop.in>
+;;; Copyright © 2021 Xinglu Chen <public@yoctocell.xyz>
+;;;
+;;; This file is part of GNU Guix.
+;;;
+;;; GNU Guix is free software; you can redistribute it and/or modify it
+;;; under the terms of the GNU General Public License as published by
+;;; the Free Software Foundation; either version 3 of the License, or (at
+;;; your option) any later version.
+;;;
+;;; GNU Guix is distributed in the hope that it will be useful, but
+;;; WITHOUT ANY WARRANTY; without even the implied warranty of
+;;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+;;; GNU General Public License for more details.
+;;;
+;;; You should have received a copy of the GNU General Public License
+;;; along with GNU Guix.  If not, see <http://www.gnu.org/licenses/>.
+
+(define-module (gnu home-services mcron)
+  #:use-module (gnu packages guile-xyz)
+  #:use-module (gnu home-services)
+  #:use-module (gnu home-services shepherd)
+  #:use-module (gnu services shepherd)
+  #:use-module (guix records)
+  #:use-module (guix gexp)
+  #:use-module (srfi srfi-1)
+  #:use-module (ice-9 match)
+
+  #:export (home-mcron-configuration
+            home-mcron-service-type))
+
+;;; Commentary:
+;;
+;; Service for the GNU mcron cron job manager.
+;;
+;; Example configuration, the first job runs mbsync once every ten
+;; minutes, the second one writes "Mcron service" to ~/mcron-file once
+;; every minute.
+;;
+;; (service home-mcron-service-type
+;;            (home-mcron-configuration
+;;             (jobs (list #~(job '(next-minute
+;;                                  (range 0 60 10))
+;;                                (lambda ()
+;;                                  (system* "mbsync" "--all")))
+;;                         #~(job next-minute-from
+;;                                (lambda ()
+;;                                  (call-with-output-file (string-append (getenv "HOME")
+;;                                                                        "/mcron-file")
+;;                                    (lambda (port)
+;;                                      (display "Mcron service" port)))))))))
+;;
+;;; Code:
+
+(define-record-type* <home-mcron-configuration> home-mcron-configuration
+  make-home-mcron-configuration
+  home-mcron-configuration?
+  (package home-mcron-configuration-package ; package
+           (default mcron))
+  (jobs home-mcron-configuration-jobs   ; list of jobs
+        (default '())))
+
+(define job-files (@@ (gnu services mcron) job-files))
+(define shepherd-schedule-action
+  (@@ (gnu services mcron) shepherd-schedule-action))
+
+(define home-mcron-shepherd-services
+  (match-lambda
+    (($ <home-mcron-configuration> mcron '()) ; no jobs to run
+     '())
+    (($ <home-mcron-configuration> mcron jobs)
+     (let ((files (job-files mcron jobs)))
+       (list (shepherd-service
+              (documentation "User cron jobs.")
+              (provision '(mcron))
+              (modules `((srfi srfi-1)
+                         (srfi srfi-26)
+                         (ice-9 popen)            ; for the 'schedule' action
+                         (ice-9 rdelim)
+                         (ice-9 match)
+                         ,@%default-modules))
+              (start #~(make-forkexec-constructor
+                        (list #$(file-append mcron "/bin/mcron") #$@files)
+                        #:log-file (string-append
+                                    (or (getenv "XDG_LOG_HOME")
+                                        (format #f "~a/.local/var/log"
+                                                (getenv "HOME")))
+                                    "/mcron.log")))
+              (stop #~(make-kill-destructor))
+              (actions
+               (list (shepherd-schedule-action mcron files)))))))))
+
+(define home-mcron-profile (compose list home-mcron-configuration-package))
+
+(define (home-mcron-extend config jobs)
+  (home-mcron-configuration
+   (inherit config)
+   (jobs (append (home-mcron-configuration-jobs config)
+                 jobs))))
+
+(define home-mcron-service-type
+  (service-type (name 'home-mcron)
+                (extensions
+                 (list (service-extension
+                        home-shepherd-service-type
+                        home-mcron-shepherd-services)
+                       (service-extension
+                        home-profile-service-type
+                        home-mcron-profile)))
+                (compose concatenate)
+                (extend home-mcron-extend)
+                (default-value (home-mcron-configuration))
+                (description
+                 "Install and configure the GNU mcron cron job manager.")))
diff --git a/gnu/home-services/shells.scm b/gnu/home-services/shells.scm
new file mode 100644
index 0000000000..ecb02098f7
--- /dev/null
+++ b/gnu/home-services/shells.scm
@@ -0,0 +1,634 @@
+;;; GNU Guix --- Functional package management for GNU
+;;; Copyright © 2021 Andrew Tropin <andrew@trop.in>
+;;; Copyright © 2021 Xinglu Chen <public@yoctocell.xyz>
+;;;
+;;; This file is part of GNU Guix.
+;;;
+;;; GNU Guix is free software; you can redistribute it and/or modify it
+;;; under the terms of the GNU General Public License as published by
+;;; the Free Software Foundation; either version 3 of the License, or (at
+;;; your option) any later version.
+;;;
+;;; GNU Guix is distributed in the hope that it will be useful, but
+;;; WITHOUT ANY WARRANTY; without even the implied warranty of
+;;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+;;; GNU General Public License for more details.
+;;;
+;;; You should have received a copy of the GNU General Public License
+;;; along with GNU Guix.  If not, see <http://www.gnu.org/licenses/>.
+
+(define-module (gnu home-services shells)
+  #:use-module (gnu services configuration)
+  #:use-module (gnu home-services configuration)
+  #:use-module (gnu home-services utils)
+  #:use-module (gnu home-services)
+  #:use-module (gnu packages shells)
+  #:use-module (gnu packages bash)
+  #:use-module (guix gexp)
+  #:use-module (guix packages)
+  #:use-module (srfi srfi-1)
+  #:use-module (srfi srfi-26)
+  #:use-module (ice-9 match)
+
+  #:export (home-shell-profile-service-type
+            home-shell-profile-configuration
+
+            home-bash-service-type
+            home-bash-configuration
+            home-bash-extension
+
+            home-zsh-service-type
+            home-zsh-configuration
+            home-zsh-extension
+
+            home-fish-service-type
+            home-fish-configuration
+            home-fish-extension))
+
+;;; Commentary:
+;;;
+;;; This module contains shell related services like Zsh.
+;;;
+;;; Code:
+
+
+;;;
+;;; Shell profile.
+;;;
+
+(define path? string?)
+(define (serialize-path field-name val) val)
+
+(define-configuration home-shell-profile-configuration
+  (profile
+   (text-config '())
+   "\
+@code{home-shell-profile} is instantiated automatically by
+@code{home-environment}, DO NOT create this service manually, it can
+only be extended.
+
+@code{profile} is a list of strings or gexps, which will go to
+@file{~/.profile}.  By default @file{~/.profile} contains the
+initialization code, which have to be evaluated by login shell to make
+home-environment's profile avaliable to the user, but other commands
+can be added to the file if it is really necessary.
+
+In most cases shell's configuration files are preferred places for
+user's customizations.  Extend home-shell-profile service only if you
+really know what you do."))
+
+(define (add-shell-profile-file config)
+  `(("profile"
+     ,(mixed-text-file
+       "shell-profile"
+       "\
+HOME_ENVIRONMENT=$HOME/.guix-home
+. $HOME_ENVIRONMENT/setup-environment
+$HOME_ENVIRONMENT/on-first-login\n"
+       (serialize-configuration
+        config
+        (filter-configuration-fields
+         home-shell-profile-configuration-fields '(profile)))))))
+
+(define (add-profile-extensions config extensions)
+  (home-shell-profile-configuration
+   (inherit config)
+   (profile
+    (append (home-shell-profile-configuration-profile config)
+            extensions))))
+
+(define home-shell-profile-service-type
+  (service-type (name 'home-shell-profile)
+                (extensions
+                 (list (service-extension
+                        home-files-service-type
+                        add-shell-profile-file)))
+                (compose concatenate)
+                (extend add-profile-extensions)
+                (default-value (home-shell-profile-configuration))
+                (description "Create @file{~/.profile}, which is used
+for environment initialization of POSIX compliant login shells.  This
+service type can be extended with a list of strings or gexps.")))
+
+(define (serialize-boolean field-name val) "")
+(define (serialize-posix-env-vars field-name val)
+  #~(string-append
+     #$@(map
+         (match-lambda
+           ((key . #f)
+            "")
+           ((key . #t)
+            #~(string-append "export " #$key "\n"))
+           ((key . value)
+            #~(string-append "export " #$key "=" #$value "\n")))
+         val)))
+
+
+;;;
+;;; Zsh.
+;;;
+
+(define-configuration home-zsh-configuration
+  (package
+    (package zsh)
+    "The Zsh package to use.")
+  (xdg-flavor?
+   (boolean #t)
+   "Place all the configs to @file{$XDG_CONFIG_HOME/zsh}.  Makes
+@file{~/.zshenv} to set @env{ZDOTDIR} to @file{$XDG_CONFIG_HOME/zsh}.
+Shell startup process will continue with
+@file{$XDG_CONFIG_HOME/zsh/.zshenv}.")
+  (environment-variables
+   (alist '())
+   "Association list of environment variables to set for the Zsh session."
+   serialize-posix-env-vars)
+  (zshenv
+   (text-config '())
+   "List of strings or gexps, which will be added to @file{.zshenv}.
+Used for setting user's shell environment variables.  Must not contain
+commands assuming the presence of tty or producing output.  Will be
+read always.  Will be read before any other file in @env{ZDOTDIR}.")
+  (zprofile
+   (text-config '())
+   "List of strings or gexps, which will be added to @file{.zprofile}.
+Used for executing user's commands at start of login shell (In most
+cases the shell started on tty just after login).  Will be read before
+@file{.zlogin}.")
+  (zshrc
+   (text-config '())
+   "List of strings or gexps, which will be added to @file{.zshrc}.
+Used for executing user's commands at start of interactive shell (The
+shell for interactive usage started by typing @code{zsh} or by
+terminal app or any other program).")
+  (zlogin
+   (text-config '())
+   "List of strings or gexps, which will be added to @file{.zlogin}.
+Used for executing user's commands at the end of starting process of
+login shell.")
+  (zlogout
+   (text-config '())
+   "List of strings or gexps, which will be added to @file{.zlogout}.
+Used for executing user's commands at the exit of login shell.  It
+won't be read in some cases (if the shell terminates by exec'ing
+another process for example)."))
+
+(define (add-zsh-configuration config)
+  (let* ((xdg-flavor? (home-zsh-configuration-xdg-flavor? config)))
+
+    (define prefix-file
+      (cut string-append
+        (if xdg-flavor?
+            "config/zsh/."
+            "") <>))
+
+    (define (filter-fields field)
+      (filter-configuration-fields home-zsh-configuration-fields
+                                   (list field)))
+
+    (define (serialize-field field)
+      (serialize-configuration
+       config
+       (filter-fields field)))
+
+    (define (file-if-not-empty field)
+      (let ((file-name (symbol->string field))
+            (field-obj (car (filter-fields field))))
+        (if (not (null? ((configuration-field-getter field-obj) config)))
+            `(,(prefix-file file-name)
+              ,(mixed-text-file
+                file-name
+                (serialize-field field)))
+            '())))
+
+    (filter
+     (compose not null?)
+     `(,(if xdg-flavor?
+            `("zshenv"
+              ,(mixed-text-file
+                "auxiliary-zshenv"
+                (if xdg-flavor?
+                    "source ${XDG_CONFIG_HOME:-$HOME/.config}/zsh/.zshenv\n"
+                    "")))
+            '())
+       (,(prefix-file "zshenv")
+        ,(mixed-text-file
+          "zshenv"
+          (if xdg-flavor?
+              "export ZDOTDIR=${XDG_CONFIG_HOME:-$HOME/.config}/zsh\n"
+              "")
+          (serialize-field 'zshenv)
+          (serialize-field 'environment-variables)))
+       (,(prefix-file "zprofile")
+        ,(mixed-text-file
+          "zprofile"
+          "\
+# Setups system and user profiles and related variables
+source /etc/profile
+# Setups home environment profile
+source ~/.profile
+
+# It's only necessary if zsh is a login shell, otherwise profiles will
+# be already sourced by bash
+"
+          (serialize-field 'zprofile)))
+
+       ,@(list (file-if-not-empty 'zshrc)
+               (file-if-not-empty 'zlogin)
+               (file-if-not-empty 'zlogout))))))
+
+(define (add-zsh-packages config)
+  (list (home-zsh-configuration-package config)))
+
+(define-configuration/no-serialization home-zsh-extension
+  (environment-variables
+   (alist '())
+   "Association list of environment variables to set.")
+  (zshrc
+   (text-config '())
+   "List of strings or gexps.")
+  (zshenv
+   (text-config '())
+   "List of strings or gexps.")
+  (zprofile
+   (text-config '())
+   "List of strings or gexps.")
+  (zlogin
+   (text-config '())
+   "List of strings or gexps.")
+  (zlogout
+   (text-config '())
+   "List of strings or gexps."))
+
+(define (home-zsh-extensions original-config extension-configs)
+  (home-zsh-configuration
+   (inherit original-config)
+   (environment-variables
+    (append (home-zsh-configuration-environment-variables original-config)
+            (append-map
+             home-zsh-extension-environment-variables extension-configs)))
+   (zshrc
+    (append (home-zsh-configuration-zshrc original-config)
+            (append-map
+             home-zsh-extension-zshrc extension-configs)))
+   (zshenv
+    (append (home-zsh-configuration-zshenv original-config)
+            (append-map
+             home-zsh-extension-zshenv extension-configs)))
+   (zprofile
+    (append (home-zsh-configuration-zprofile original-config)
+            (append-map
+             home-zsh-extension-zprofile extension-configs)))
+   (zlogin
+    (append (home-zsh-configuration-zlogin original-config)
+            (append-map
+             home-zsh-extension-zlogin extension-configs)))
+   (zlogout
+    (append (home-zsh-configuration-zlogout original-config)
+            (append-map
+             home-zsh-extension-zlogout extension-configs)))))
+
+(define home-zsh-service-type
+  (service-type (name 'home-zsh)
+                (extensions
+                 (list (service-extension
+                        home-files-service-type
+                        add-zsh-configuration)
+                       (service-extension
+                        home-profile-service-type
+                        add-zsh-packages)))
+                (compose identity)
+                (extend home-zsh-extensions)
+                (default-value (home-zsh-configuration))
+                (description "Install and configure Zsh.")))
+
+
+;;;
+;;; Bash.
+;;;
+
+(define-configuration home-bash-configuration
+  (package
+   (package bash)
+   "The Bash package to use.")
+  (guix-defaults?
+   (boolean #t)
+   "Add sane defaults like reading @file{/etc/bashrc}, coloring output
+for @code{ls} provided by guix to @file{.bashrc}.")
+  (environment-variables
+   (alist '())
+   "Association list of environment variables to set for the Bash session."
+   serialize-posix-env-vars)
+  (bash-profile
+   (text-config '())
+   "List of strings or gexps, which will be added to @file{.bash_profile}.
+Used for executing user's commands at start of login shell (In most
+cases the shell started on tty just after login).  @file{.bash_login}
+won't be ever read, because @file{.bash_profile} always present.")
+  (bashrc
+   (text-config '())
+   "List of strings or gexps, which will be added to @file{.bashrc}.
+Used for executing user's commands at start of interactive shell (The
+shell for interactive usage started by typing @code{bash} or by
+terminal app or any other program).")
+  (bash-logout
+   (text-config '())
+   "List of strings or gexps, which will be added to @file{.bash_logout}.
+Used for executing user's commands at the exit of login shell.  It
+won't be read in some cases (if the shell terminates by exec'ing
+another process for example)."))
+
+;; TODO: Use value from (gnu system shadow)
+(define guix-bashrc
+  "\
+# Bash initialization for interactive non-login shells and
+# for remote shells (info \"(bash) Bash Startup Files\").
+
+# Export 'SHELL' to child processes.  Programs such as 'screen'
+# honor it and otherwise use /bin/sh.
+export SHELL
+
+if [[ $- != *i* ]]
+then
+    # We are being invoked from a non-interactive shell.  If this
+    # is an SSH session (as in \"ssh host command\"), source
+    # /etc/profile so we get PATH and other essential variables.
+    [[ -n \"$SSH_CLIENT\" ]] && source /etc/profile
+
+    # Don't do anything else.
+    return
+fi
+
+# Source the system-wide file.
+source /etc/bashrc
+
+# Adjust the prompt depending on whether we're in 'guix environment'.
+if [ -n \"$GUIX_ENVIRONMENT\" ]
+then
+    PS1='\\u@\\h \\w [env]\\$ '
+else
+    PS1='\\u@\\h \\w\\$ '
+fi
+alias ls='ls -p --color=auto'
+alias ll='ls -l'
+alias grep='grep --color=auto'\n")
+
+(define (add-bash-configuration config)
+  (define (filter-fields field)
+    (filter-configuration-fields home-bash-configuration-fields
+                                 (list field)))
+
+  (define (serialize-field field)
+    (serialize-configuration
+     config
+     (filter-fields field)))
+
+  (define* (file-if-not-empty field #:optional (extra-content #f))
+    (let ((file-name (symbol->string field))
+          (field-obj (car (filter-fields field))))
+      (if (or extra-content
+              (not (null? ((configuration-field-getter field-obj) config))))
+          `(,(object->snake-case-string file-name)
+            ,(mixed-text-file
+              (object->snake-case-string file-name)
+              (if extra-content extra-content "")
+              (serialize-field field)))
+          '())))
+
+  (filter
+   (compose not null?)
+   `(("bash_profile"
+      ,(mixed-text-file
+        "bash_profile"
+        "\
+# Setups system and user profiles and related variables
+# /etc/profile will be sourced by bash automatically
+# Setups home environment profile
+if [ -f ~/.profile ]; then source ~/.profile; fi
+
+# Honor per-interactive-shell startup file
+if [ -f ~/.bashrc ]; then source ~/.bashrc; fi
+"
+        (serialize-field 'bash-profile)
+        (serialize-field 'environment-variables)))
+
+     ,@(list (file-if-not-empty
+              'bashrc
+              (if (home-bash-configuration-guix-defaults? config)
+                  guix-bashrc
+                  #f))
+             (file-if-not-empty 'bash-logout)))))
+
+(define (add-bash-packages config)
+  (list (home-bash-configuration-package config)))
+
+(define-configuration/no-serialization home-bash-extension
+  (environment-variables
+   (alist '())
+   "Association list of environment variables to set.")
+  (bash-profile
+   (text-config '())
+   "List of strings or gexps.")
+  (bashrc
+   (text-config '())
+   "List of strings or gexps.")
+  (bash-logout
+   (text-config '())
+   "List of strings or gexps."))
+
+(define (home-bash-extensions original-config extension-configs)
+  (home-bash-configuration
+   (inherit original-config)
+   (environment-variables
+    (append (home-bash-configuration-environment-variables original-config)
+            (append-map
+             home-bash-extension-environment-variables extension-configs)))
+   (bash-profile
+    (append (home-bash-configuration-bash-profile original-config)
+            (append-map
+             home-bash-extension-bash-profile extension-configs)))
+   (bashrc
+    (append (home-bash-configuration-bashrc original-config)
+            (append-map
+             home-bash-extension-bashrc extension-configs)))
+   (bash-logout
+    (append (home-bash-configuration-bash-logout original-config)
+            (append-map
+             home-bash-extension-bash-logout extension-configs)))))
+
+(define home-bash-service-type
+  (service-type (name 'home-bash)
+                (extensions
+                 (list (service-extension
+                        home-files-service-type
+                        add-bash-configuration)
+                       (service-extension
+                        home-profile-service-type
+                        add-bash-packages)))
+                (compose identity)
+                (extend home-bash-extensions)
+                (default-value (home-bash-configuration))
+                (description "Install and configure GNU Bash.")))
+
+
+;;;
+;;; Fish.
+;;;
+
+(define (serialize-fish-aliases field-name val)
+  #~(string-append
+     #$@(map (match-lambda
+               ((key . value)
+                #~(string-append "alias " #$key " \"" #$value "\"\n"))
+               (_ ""))
+             val)))
+
+(define (serialize-fish-abbreviations field-name val)
+  #~(string-append
+     #$@(map (match-lambda
+               ((key . value)
+                #~(string-append "abbr --add " #$key " " #$value "\n"))
+               (_ ""))
+             val)))
+
+(define (serialize-fish-env-vars field-name val)
+  #~(string-append
+     #$@(map (match-lambda
+               ((key . #f)
+                "")
+               ((key . #t)
+                #~(string-append "set " #$key "\n"))
+               ((key . value)
+                #~(string-append "set " #$key " "  #$value "\n")))
+             val)))
+
+(define-configuration home-fish-configuration
+  (package
+    (package fish)
+    "The Fish package to use.")
+  (config
+   (text-config '())
+   "List of strings or gexps, which will be added to
+@file{$XDG_CONFIG_HOME/fish/config.fish}.")
+  (environment-variables
+   (alist '())
+   "Association list of environment variables to set in Fish."
+   serialize-fish-env-vars)
+  (aliases
+   (alist '())
+   "Association list of aliases for Fish, both the key and the value
+should be a string.  An alias is just a simple function that wraps a
+command, If you want something more akin to @dfn{aliases} in POSIX
+shells, see the @code{abbreviations} field."
+   serialize-fish-aliases)
+  (abbreviations
+   (alist '())
+   "Association list of abbreviations for Fish.  These are words that,
+when typed in the shell, will automatically expand to the full text."
+   serialize-fish-abbreviations))
+
+(define (fish-files-service config)
+  `(("config/fish/config.fish"
+     ,(mixed-text-file
+       "fish-config.fish"
+       #~(string-append "\
+# if we haven't sourced the login config, do it
+status --is-login; and not set -q __fish_login_config_sourced
+and begin
+
+  set --prepend fish_function_path "
+                        #$fish-foreign-env
+                        "/share/fish/functions
+  fenv source $HOME/.profile
+  set -e fish_function_path[1]
+
+  set -g __fish_login_config_sourced 1
+
+end\n\n")
+       (serialize-configuration
+        config
+        home-fish-configuration-fields)))))
+
+(define (fish-profile-service config)
+  (list (home-fish-configuration-package config)))
+
+(define-configuration/no-serialization home-fish-extension
+  (config
+   (text-config '())
+   "List of strings or gexps for extending the Fish initialization file.")
+  (environment-variables
+   (alist '())
+   "Association list of environment variables to set.")
+  (aliases
+   (alist '())
+   "Association list of Fish aliases.")
+  (abbreviations
+   (alist '())
+   "Association list of Fish abbreviations."))
+
+(define (home-fish-extensions original-config extension-configs)
+  (home-fish-configuration
+   (inherit original-config)
+   (config
+    (append (home-fish-configuration-config original-config)
+            (append-map
+             home-fish-extension-config extension-configs)))
+   (environment-variables
+    (append (home-fish-configuration-environment-variables original-config)
+            (append-map
+             home-fish-extension-environment-variables extension-configs)))
+   (aliases
+    (append (home-fish-configuration-aliases original-config)
+            (append-map
+             home-fish-extension-aliases extension-configs)))
+   (abbreviations
+    (append (home-fish-configuration-abbreviations original-config)
+            (append-map
+             home-fish-extension-abbreviations extension-configs)))))
+
+;; TODO: Support for generating completion files
+;; TODO: Support for installing plugins
+(define home-fish-service-type
+  (service-type (name 'home-fish)
+                (extensions
+                 (list (service-extension
+                        home-files-service-type
+                        fish-files-service)
+                       (service-extension
+                        home-profile-service-type
+                        fish-profile-service)))
+                (compose identity)
+                (extend home-fish-extensions)
+                (default-value (home-fish-configuration))
+                (description "\
+Install and configure Fish, the friendly interactive shell.")))
+
+
+(define (generate-home-shell-profile-documentation)
+  (generate-documentation
+   `((home-shell-profile-configuration
+      ,home-shell-profile-configuration-fields))
+   'home-shell-profile-configuration))
+
+(define (generate-home-bash-documentation)
+  (generate-documentation
+   `((home-bash-configuration
+      ,home-bash-configuration-fields))
+   'home-bash-configuration))
+
+(define (generate-home-zsh-documentation)
+  (generate-documentation
+   `((home-zsh-configuration
+      ,home-zsh-configuration-fields))
+   'home-zsh-configuration))
+
+(define (generate-home-fish-documentation)
+  (string-append
+   (generate-documentation
+    `((home-fish-configuration
+       ,home-fish-configuration-fields))
+    'home-fish-configuration)
+   "\n\n"
+   (generate-documentation
+    `((home-fish-extension
+       ,home-fish-extension-fields))
+    'home-fish-extension)))
diff --git a/gnu/home-services/shepherd.scm b/gnu/home-services/shepherd.scm
new file mode 100644
index 0000000000..120cfde1a1
--- /dev/null
+++ b/gnu/home-services/shepherd.scm
@@ -0,0 +1,134 @@
+;;; GNU Guix --- Functional package management for GNU
+;;; Copyright © 2021 Andrew Tropin <andrew@trop.in>
+;;; Copyright © 2021 Xinglu Chen <public@yoctocell.xyz>
+;;;
+;;; This file is part of GNU Guix.
+;;;
+;;; GNU Guix is free software; you can redistribute it and/or modify it
+;;; under the terms of the GNU General Public License as published by
+;;; the Free Software Foundation; either version 3 of the License, or (at
+;;; your option) any later version.
+;;;
+;;; GNU Guix is distributed in the hope that it will be useful, but
+;;; WITHOUT ANY WARRANTY; without even the implied warranty of
+;;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+;;; GNU General Public License for more details.
+;;;
+;;; You should have received a copy of the GNU General Public License
+;;; along with GNU Guix.  If not, see <http://www.gnu.org/licenses/>.
+
+(define-module (gnu home-services shepherd)
+  #:use-module (gnu home-services)
+  #:use-module (gnu packages admin)
+  #:use-module (gnu services shepherd)
+  #:use-module (guix sets)
+  #:use-module (guix gexp)
+  #:use-module (guix records)
+
+  #:use-module (srfi srfi-1)
+
+  #:export (home-shepherd-service-type
+            home-shepherd-configuration)
+  #:re-export (shepherd-service
+               shepherd-action))
+
+(define-record-type* <home-shepherd-configuration>
+  home-shepherd-configuration make-home-shepherd-configuration
+  home-shepherd-configuration?
+  (shepherd home-shepherd-configuration-shepherd
+            (default shepherd)) ; package
+  (auto-start? home-shepherd-configuration-auto-start?
+               (default #t))
+  (services home-shepherd-configuration-services
+            (default '())))
+
+(define (home-shepherd-configuration-file services shepherd)
+  "Return the shepherd configuration file for SERVICES.  SHEPHERD is used
+as shepherd package."
+  (assert-valid-graph services)
+
+  (let ((files (map shepherd-service-file services))
+        ;; TODO: Add compilation of services, it can improve start
+        ;; time.
+        ;; (scm->go (cute scm->go <> shepherd))
+        )
+    (define config
+      #~(begin
+          (use-modules (srfi srfi-34)
+                       (system repl error-handling))
+          (apply
+           register-services
+           (map
+            (lambda (file) (load file))
+            '#$files))
+          (action 'root 'daemonize)
+          (format #t "Starting services...~%")
+          (for-each
+           (lambda (service) (start service))
+           '#$(append-map shepherd-service-provision
+                          (filter shepherd-service-auto-start?
+                                  services)))
+          (newline)))
+
+    (scheme-file "shepherd.conf" config)))
+
+(define (launch-shepherd-gexp config)
+  (let* ((shepherd (home-shepherd-configuration-shepherd config))
+         (services (home-shepherd-configuration-services config)))
+    (if (home-shepherd-configuration-auto-start? config)
+        (with-imported-modules '((guix build utils))
+          #~(let ((log-dir (or (getenv "XDG_LOG_HOME")
+                               (format #f "~a/.local/var/log" (getenv "HOME")))))
+              ((@ (guix build utils) mkdir-p) log-dir)
+              (system*
+               #$(file-append shepherd "/bin/shepherd")
+               "--logfile"
+               (string-append
+                log-dir
+                "/shepherd.log")
+               "--config"
+               #$(home-shepherd-configuration-file services shepherd))))
+        #~"")))
+
+(define (reload-configuration-gexp config)
+  (let* ((shepherd (home-shepherd-configuration-shepherd config))
+         (services (home-shepherd-configuration-services config)))
+    #~(system*
+       #$(file-append shepherd "/bin/herd")
+       "load" "root"
+       #$(home-shepherd-configuration-file services shepherd))))
+
+(define (ensure-shepherd-gexp config)
+  #~(if (file-exists?
+         (string-append
+          (or (getenv "XDG_RUNTIME_DIR")
+              (format #f "/run/user/~a" (getuid)))
+          "/shepherd/socket"))
+        #$(reload-configuration-gexp config)
+        #$(launch-shepherd-gexp config)))
+
+(define-public home-shepherd-service-type
+  (service-type (name 'home-shepherd)
+                (extensions
+                 (list (service-extension
+                        home-run-on-first-login-service-type
+                        launch-shepherd-gexp)
+                       (service-extension
+                        home-activation-service-type
+                        ensure-shepherd-gexp)
+                       (service-extension
+                        home-profile-service-type
+                        (lambda (config)
+                          `(,(home-shepherd-configuration-shepherd config))))))
+                (compose concatenate)
+                (extend
+                 (lambda (config extra-services)
+                   (home-shepherd-configuration
+                    (inherit config)
+                    (services
+                     (append (home-shepherd-configuration-services config)
+                             extra-services)))))
+                (default-value (home-shepherd-configuration))
+                (description "Configure and install userland Shepherd.")))
+
+
diff --git a/gnu/home-services/symlink-manager.scm b/gnu/home-services/symlink-manager.scm
new file mode 100644
index 0000000000..11f5d503d4
--- /dev/null
+++ b/gnu/home-services/symlink-manager.scm
@@ -0,0 +1,247 @@
+;;; GNU Guix --- Functional package management for GNU
+;;; Copyright © 2021 Andrew Tropin <andrew@trop.in>
+;;; Copyright © 2021 Xinglu Chen <public@yoctocell.xyz>
+;;;
+;;; This file is part of GNU Guix.
+;;;
+;;; GNU Guix is free software; you can redistribute it and/or modify it
+;;; under the terms of the GNU General Public License as published by
+;;; the Free Software Foundation; either version 3 of the License, or (at
+;;; your option) any later version.
+;;;
+;;; GNU Guix is distributed in the hope that it will be useful, but
+;;; WITHOUT ANY WARRANTY; without even the implied warranty of
+;;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+;;; GNU General Public License for more details.
+;;;
+;;; You should have received a copy of the GNU General Public License
+;;; along with GNU Guix.  If not, see <http://www.gnu.org/licenses/>.
+
+(define-module (gnu home-services symlink-manager)
+  #:use-module (gnu home-services)
+  #:use-module (guix gexp)
+
+  #:export (home-symlink-manager-service-type))
+
+;;; Comment:
+;;;
+;;; symlink-manager cares about configuration files: it backs up files
+;;; created by user, removes symlinks and directories created by a
+;;; previous generation, and creates new directories and symlinks to
+;;; configuration files according to the content of files/ directory
+;;; (created by home-files-service) of the current home environment
+;;; generation.
+;;;
+;;; Code:
+
+(define (update-symlinks-script)
+  (program-file
+   "update-symlinks"
+   #~(begin
+       (use-modules (ice-9 ftw)
+                    (ice-9 curried-definitions)
+                    (ice-9 match)
+                    (srfi srfi-1))
+       (define ((simplify-file-tree parent) file)
+         "Convert the result produced by `file-system-tree' to less
+verbose and more suitable for further processing format.
+
+Extract dir/file info from stat and compose a relative path to the
+root of the file tree.
+
+Sample output:
+
+((dir . \".\")
+ ((dir . \"config\")
+  ((dir . \"config/fontconfig\")
+   (file . \"config/fontconfig/fonts.conf\"))
+  ((dir . \"config/isync\")
+   (file . \"config/isync/mbsyncrc\"))))
+"
+         (match file
+           ((name stat) `(file . ,(string-append parent name)))
+           ((name stat children ...)
+            (cons `(dir . ,(string-append parent name))
+                  (map (simplify-file-tree
+                        (if (equal? name ".")
+                            ""
+                            (string-append parent name "/")))
+                       children)))))
+
+       (define ((file-tree-traverse preordering) node)
+         "Traverses the file tree in different orders, depending on PREORDERING.
+
+if PREORDERING is @code{#t} resulting list will contain directories
+before files located in those directories, otherwise directory will
+appear only after all nested items already listed."
+         (let ((prepend (lambda (a b) (append b a))))
+           (match node
+             (('file . path) (list node))
+             ((('dir . path) . rest)
+              ((if preordering append prepend)
+               (list (cons 'dir path))
+               (append-map (file-tree-traverse preordering) rest))))))
+
+       (use-modules (guix build utils))
+
+       (let* ((config-home    (or (getenv "XDG_CONFIG_HOME")
+                                  (string-append (getenv "HOME") "/.config")))
+
+              (he-path (string-append (getenv "HOME") "/.guix-home"))
+              (new-he-path (string-append he-path ".new"))
+              (new-home (getenv "GUIX_NEW_HOME"))
+              (old-home (getenv "GUIX_OLD_HOME"))
+
+              (new-files-path (string-append new-home "/files"))
+              ;; Trailing dot is required, because files itself is symlink and
+              ;; to make file-system-tree works it should be a directory.
+              (new-files-dir-path (string-append new-files-path "/."))
+
+              (home-path (getenv "HOME"))
+              (backup-dir (string-append home-path "/"
+                                         (number->string (current-time))
+                                         "-guix-home-legacy-configs-backup"))
+
+              (old-tree (if old-home
+                          ((simplify-file-tree "")
+                           (file-system-tree
+                            (string-append old-home "/files/.")))
+                          #f))
+              (new-tree ((simplify-file-tree "")
+                         (file-system-tree new-files-dir-path)))
+
+              (get-source-path
+               (lambda (path)
+                 (readlink (string-append new-files-path "/" path))))
+
+              (get-target-path
+               (lambda (path)
+                 (string-append home-path "/." path)))
+
+              (get-backup-path
+               (lambda (path)
+                 (string-append backup-dir "/." path)))
+
+              (directory?
+               (lambda (path)
+                 (equal? (stat:type (stat path)) 'directory)))
+
+              (empty-directory?
+               (lambda (dir)
+                 (equal? (scandir dir) '("." ".."))))
+
+              (symlink-to-store?
+               (lambda (path)
+                 (and
+                  (equal? (stat:type (lstat path)) 'symlink)
+                  (store-file-name? (readlink path)))))
+
+              (backup-file
+               (lambda (path)
+                 (mkdir-p backup-dir)
+                 (format #t "Backing up ~a..." (get-target-path path))
+                 (mkdir-p (dirname (get-backup-path path)))
+                 (rename-file (get-target-path path) (get-backup-path path))
+                 (display " done\n")))
+
+              (cleanup-symlinks
+               (lambda ()
+                 (let ((to-delete ((file-tree-traverse #f) old-tree)))
+                   (display
+                    "Cleaning up symlinks from previous home-environment.\n\n")
+                   (map
+                    (match-lambda
+                      (('dir . ".")
+                       (display "Cleanup finished.\n\n"))
+
+                      (('dir . path)
+                       (if (and
+                            (file-exists? (get-target-path path))
+                            (directory? (get-target-path path))
+                            (empty-directory? (get-target-path path)))
+                           (begin
+                             (format #t "Removing ~a..."
+                                     (get-target-path path))
+                             (rmdir (get-target-path path))
+                             (display " done\n"))
+                           (format
+                            #t "Skipping ~a (not an empty directory)... done\n"
+                            (get-target-path path))))
+
+                      (('file . path)
+                       (when (file-exists? (get-target-path path))
+                         ;; DO NOT remove the file if it is no longer
+                         ;; a symlink to the store, it will be backed
+                         ;; up later during create-symlinks phase.
+                         (if (symlink-to-store? (get-target-path path))
+                             (begin
+                               (format #t "Removing ~a..." (get-target-path path))
+                               (delete-file (get-target-path path))
+                               (display " done\n"))
+                             (format
+                              #t
+                              "Skipping ~a (not a symlink to store)... done\n"
+                              (get-target-path path))))))
+                    to-delete))))
+
+              (create-symlinks
+               (lambda ()
+                 (let ((to-create ((file-tree-traverse #t) new-tree)))
+                   (map
+                    (match-lambda
+                      (('dir . ".")
+                       (display
+                        "New symlinks to home-environment will be created soon.\n")
+                       (format
+                        #t "All conflicting files will go to ~a.\n\n" backup-dir))
+
+                      (('dir . path)
+                       (let ((target-path (get-target-path path)))
+                         (when (and (file-exists? target-path)
+                                    (not (directory? target-path)))
+                           (backup-file path))
+
+                         (if (file-exists? target-path)
+                             (format
+                              #t "Skipping   ~a (directory already exists)... done\n"
+                              target-path)
+                             (begin
+                               (format #t "Creating   ~a..." target-path)
+                               (mkdir target-path)
+                               (display " done\n")))))
+
+                      (('file . path)
+                       (when (file-exists? (get-target-path path))
+                         (backup-file path))
+                       (format #t "Symlinking ~a -> ~a..."
+                               (get-target-path path) (get-source-path path))
+                       (symlink (get-source-path path) (get-target-path path))
+                       (display " done\n")))
+                    to-create)))))
+
+         (when old-tree
+           (cleanup-symlinks))
+
+         (create-symlinks)
+
+         (symlink new-home new-he-path)
+         (rename-file new-he-path he-path)
+
+         (display " done\nFinished updating symlinks.\n\n")))))
+
+
+(define (update-symlinks-gexp _)
+  #~(primitive-load #$(update-symlinks-script)))
+
+(define home-symlink-manager-service-type
+  (service-type (name 'home-symlink-manager)
+                (extensions
+                 (list
+                  (service-extension
+                   home-activation-service-type
+                   update-symlinks-gexp)))
+                (default-value #f)
+                (description "Provide an @code{update-symlinks}
+script, which creates symlinks to configuration files and directories
+on every activation.  If an existing file would be overwritten by a
+symlink, backs up that file first.")))
diff --git a/gnu/home-services/utils.scm b/gnu/home-services/utils.scm
new file mode 100644
index 0000000000..3e490a0515
--- /dev/null
+++ b/gnu/home-services/utils.scm
@@ -0,0 +1,77 @@
+;;; GNU Guix --- Functional package management for GNU
+;;; Copyright © 2021 Xinglu Chen <public@yoctocell.xyz>
+;;; Copyright © 2021 Andrew Tropin <andrew@trop.in>
+;;;
+;;; This file is part of GNU Guix.
+;;;
+;;; GNU Guix is free software; you can redistribute it and/or modify it
+;;; under the terms of the GNU General Public License as published by
+;;; the Free Software Foundation; either version 3 of the License, or (at
+;;; your option) any later version.
+;;;
+;;; GNU Guix is distributed in the hope that it will be useful, but
+;;; WITHOUT ANY WARRANTY; without even the implied warranty of
+;;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+;;; GNU General Public License for more details.
+;;;
+;;; You should have received a copy of the GNU General Public License
+;;; along with GNU Guix.  If not, see <http://www.gnu.org/licenses/>.
+
+(define-module (gnu home-services utils)
+  #:use-module (ice-9 string-fun)
+  #:use-module (srfi srfi-1)
+  #:use-module (srfi srfi-26)
+
+  #:export (maybe-object->string
+            object->snake-case-string
+            object->camel-case-string))
+
+(define (maybe-object->string object)
+  "Like @code{object->string} but don't do anyting if OBJECT already is
+a string."
+  (if (string? object)
+      object
+      (object->string object)))
+
+;; Snake case: <https://en.wikipedia.org/wiki/Snake_case>
+(define* (object->snake-case-string object #:optional (style 'lower))
+  "Convert the object OBJECT to the equivalent string in ``snake
+case''.  STYLE can be three `@code{lower}', `@code{upper}', or
+`@code{capitalize}', defaults to `@code{lower}'.
+
+@example
+(object->snake-case-string 'variable-name 'upper)
+@result{} \"VARIABLE_NAME\" @end example"
+  (if (not (member style '(lower upper capitalize)))
+      (error 'invalid-style (format #f "~a is not a valid style" style))
+      (let ((stringified (maybe-object->string object)))
+        (string-replace-substring
+         (cond
+          ((equal? style 'lower) stringified)
+          ((equal? style 'upper) (string-upcase stringified))
+          (else (string-capitalize stringified)))
+         "-" "_"))))
+
+(define* (object->camel-case-string object #:optional (style 'lower))
+  "Convert the object OBJECT to the equivalent string in ``camel case''.
+STYLE can be three `@code{lower}', `@code{upper}', defaults to
+`@code{lower}'.
+
+@example
+(object->camel-case-string 'variable-name 'upper)
+@result{} \"VariableName\"
+@end example"
+  (if (not (member style '(lower upper)))
+      (error 'invalid-style (format #f "~a is not a valid style" style))
+      (let ((stringified (maybe-object->string object)))
+        (cond
+         ((eq? style 'upper)
+          (string-concatenate
+           (map string-capitalize
+                (string-split stringified (cut eqv? <> #\-)))))
+         ((eq? style 'lower)
+          (let ((splitted-string (string-split stringified (cut eqv? <> #\-))))
+            (string-concatenate
+             (cons (first splitted-string)
+                   (map string-capitalize
+                        (cdr splitted-string))))))))))
diff --git a/gnu/home-services/xdg.scm b/gnu/home-services/xdg.scm
new file mode 100644
index 0000000000..457ce999a1
--- /dev/null
+++ b/gnu/home-services/xdg.scm
@@ -0,0 +1,476 @@
+;;; GNU Guix --- Functional package management for GNU
+;;; Copyright © 2021 Andrew Tropin <andrew@trop.in>
+;;; Copyright © 2021 Xinglu Chen <public@yoctocell.xyz>
+;;;
+;;; This file is part of GNU Guix.
+;;;
+;;; GNU Guix is free software; you can redistribute it and/or modify it
+;;; under the terms of the GNU General Public License as published by
+;;; the Free Software Foundation; either version 3 of the License, or (at
+;;; your option) any later version.
+;;;
+;;; GNU Guix is distributed in the hope that it will be useful, but
+;;; WITHOUT ANY WARRANTY; without even the implied warranty of
+;;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+;;; GNU General Public License for more details.
+;;;
+;;; You should have received a copy of the GNU General Public License
+;;; along with GNU Guix.  If not, see <http://www.gnu.org/licenses/>.
+
+(define-module (gnu home-services xdg)
+  #:use-module (gnu services configuration)
+  #:use-module (gnu home-services configuration)
+  #:use-module (gnu home-services)
+  #:use-module (gnu packages freedesktop)
+  #:use-module (gnu home-services utils)
+  #:use-module (guix gexp)
+  #:use-module (guix records)
+  #:use-module (guix i18n)
+  #:use-module (guix diagnostics)
+
+  #:use-module (ice-9 match)
+  #:use-module (srfi srfi-1)
+  #:use-module (rnrs enums)
+
+  #:export (home-xdg-base-directories-service-type
+            home-xdg-base-directories-configuration
+            home-xdg-base-directories-configuration?
+
+            home-xdg-user-directories-service-type
+            home-xdg-user-directories-configuration
+            home-xdg-user-directories-configuration?
+
+            xdg-desktop-action
+            xdg-desktop-entry
+            home-xdg-mime-applications-service-type
+            home-xdg-mime-applications-configuration))
+
+;;; Commentary:
+;;
+;; This module contains services related to XDG directories and
+;; applications.
+;;
+;; - XDG base directories
+;; - XDG user directories
+;; - XDG MIME applications
+;;
+;;; Code:
+
+
+;;;
+;;; XDG base directories.
+;;;
+
+(define (serialize-path field-name val) "")
+(define path? string?)
+
+(define-configuration home-xdg-base-directories-configuration
+  (cache-home
+   (path "$HOME/.cache")
+   "Base directory for programs to store user-specific non-essential
+(cached) data.  Files in this directory can be deleted anytime without
+loss of important data.")
+  (config-home
+   (path "$HOME/.config")
+   "Base directory for programs to store configuration files.
+Some programs store here log or state files, but it's not desired,
+this directory should contain static configurations.")
+  (data-home
+   (path "$HOME/.local/share")
+   "Base directory for programs to store architecture independent
+read-only shared data, analogus to @file{/usr/share}, but for user.")
+  (runtime-dir
+   (path "${XDG_RUNTIME_DIR:-/run/user/$UID}")
+   "Base directory for programs to store user-specific runtime files,
+like sockets.")
+  (log-home
+   (path "$HOME/.local/var/log")
+   "Base directory for programs to store log files, analogus to
+@file{/var/log}, but for user.  It is not a part of XDG Base Directory
+Specification, but helps to make implementation of home services more
+consistent.")
+  (state-home
+   (path "$HOME/.local/var/lib")
+   "Base directory for programs to store state files, like databases,
+analogus to @file{/var/lib}, but for user.  It is not a part of XDG
+Base Directory Specification, but helps to make implementation of home
+services more consistent."))
+
+(define (home-xdg-base-directories-environment-variables-service config)
+  (map
+   (lambda (field)
+     (cons (format
+            #f "XDG_~a"
+            (object->snake-case-string (configuration-field-name field) 'upper))
+           ((configuration-field-getter field) config)))
+   home-xdg-base-directories-configuration-fields))
+
+(define (ensure-xdg-base-dirs-on-activation config)
+  #~(map (lambda (xdg-base-dir-variable)
+           ((@@ (guix build utils) mkdir-p)
+            (getenv
+             xdg-base-dir-variable)))
+         '#$(map (lambda (field)
+                   (format
+                    #f "XDG_~a"
+                    (object->snake-case-string
+                     (configuration-field-name field) 'upper)))
+                 home-xdg-base-directories-configuration-fields)))
+
+(define (last-extension-or-cfg config extensions)
+  "Picks configuration value from last provided extension.  If there
+are no extensions use configuration instead."
+  (or (and (not (null? extensions)) (last extensions)) config))
+
+(define home-xdg-base-directories-service-type
+  (service-type (name 'home-xdg-base-directories)
+                (extensions
+                 (list (service-extension
+                        home-environment-variables-service-type
+                        home-xdg-base-directories-environment-variables-service)
+                       (service-extension
+                        home-activation-service-type
+                        ensure-xdg-base-dirs-on-activation)))
+                (default-value (home-xdg-base-directories-configuration))
+                (compose identity)
+                (extend last-extension-or-cfg)
+                (description "Configure XDG base directories.  This
+service introduces two additional variables @env{XDG_STATE_HOME},
+@env{XDG_LOG_HOME}.  They are not a part of XDG specification, at
+least yet, but are convinient to have, it improves the consistency
+between different home services.  The services of this service-type is
+instantiated by default, to provide non-default value, extend the
+service-type (using @code{simple-service} for example).")))
+
+(define (generate-home-xdg-base-directories-documentation)
+  (generate-documentation
+   `((home-xdg-base-directories-configuration
+      ,home-xdg-base-directories-configuration-fields))
+   'home-xdg-base-directories-configuration))
+
+
+;;;
+;;; XDG user directories.
+;;;
+
+(define (serialize-string field-name val)
+  ;; The path has to be quoted
+  (format #f "XDG_~a_DIR=\"~a\"\n"
+          (object->snake-case-string field-name 'upper) val))
+
+(define-configuration home-xdg-user-directories-configuration
+  (desktop
+   (string "$HOME/Desktop")
+   "Default ``desktop'' directory, this is what you see on your
+desktop when using a desktop environment,
+e.g. GNOME (@pxref{XWindow,,,guix.info}).")
+  (documents
+   (string "$HOME/Documents")
+   "Default directory to put documents like PDFs.")
+  (download
+   (string "$HOME/Downloads")
+   "Default directory downloaded files, this is where your Web-broser
+will put downloaded files in.")
+  (music
+   (string "$HOME/Music")
+   "Default directory for audio files.")
+  (pictures
+   (string "$HOME/Pictures")
+   "Default directory for pictures and images.")
+  (publicshare
+   (string "$HOME/Public")
+   "Default directory for shared files, which can be accessed by other
+users on local machine or via network.")
+  (templates
+   (string "$HOME/Templates")
+   "Default directory for templates.  They can be used by graphical
+file manager or other apps for creating new files with some
+pre-populated content.")
+  (videos
+   (string "$HOME/Videos")
+   "Default directory for videos."))
+
+(define (home-xdg-user-directories-files-service config)
+  `(("config/user-dirs.conf"
+     ,(mixed-text-file
+       "user-dirs.conf"
+       "enabled=False\n"))
+    ("config/user-dirs.dirs"
+     ,(mixed-text-file
+       "user-dirs.dirs"
+      (serialize-configuration
+       config
+       home-xdg-user-directories-configuration-fields)))))
+
+(define (home-xdg-user-directories-activation-service config)
+  (let ((dirs (map (lambda (field)
+                     ((configuration-field-getter field) config))
+                   home-xdg-user-directories-configuration-fields)))
+    #~(let ((ensure-dir
+             (lambda (path)
+               (mkdir-p
+                ((@@ (ice-9 string-fun) string-replace-substring)
+                 path "$HOME" (getenv "HOME"))))))
+        (display "Creating XDG user directories...")
+        (map ensure-dir '#$dirs)
+        (display " done\n"))))
+
+(define home-xdg-user-directories-service-type
+  (service-type (name 'home-xdg-user-directories)
+                (extensions
+                 (list (service-extension
+                        home-files-service-type
+                        home-xdg-user-directories-files-service)
+                       (service-extension
+                        home-activation-service-type
+                        home-xdg-user-directories-activation-service)))
+                (default-value (home-xdg-user-directories-configuration))
+                (description "Configure XDG user directories.  To
+disable a directory, point it to the $HOME.")))
+
+(define (generate-home-xdg-user-directories-documentation)
+  (generate-documentation
+   `((home-xdg-user-directories-configuration
+     ,home-xdg-user-directories-configuration-fields))
+   'home-xdg-user-directories-configuration))
+
+
+;;;
+;;; XDG MIME applications.
+;;;
+
+;; Example config
+;;
+;;  (home-xdg-mime-applications-configuration
+;;   (added '((x-scheme-handler/magnet . torrent.desktop)))
+;;   (default '((inode/directory . file.desktop)))
+;;   (removed '((inode/directory . thunar.desktop)))
+;;   (desktop-entries
+;;    (list (xdg-desktop-entry
+;;           (file "file")
+;;           (name "File manager")
+;;           (type 'application)
+;;           (config
+;;            '((exec . "emacsclient -c -a emacs %u"))))
+;;          (xdg-desktop-entry
+;;           (file "text")
+;;           (name "Text editor")
+;;           (type 'application)
+;;           (config
+;;            '((exec . "emacsclient -c -a emacs %u")))
+;;           (actions
+;;            (list (xdg-desktop-action
+;;                   (action 'create)
+;;                   (name "Create an action")
+;;                   (config
+;;                    '((exec . "echo hi"))))))))))
+
+;; See
+;; <https://specifications.freedesktop.org/shared-mime-info-spec/shared-mime-info-spec-latest.html>
+;; <https://specifications.freedesktop.org/mime-apps-spec/mime-apps-spec-latest.html>
+
+(define (serialize-alist field-name val)
+  (define (serialize-mimelist-entry key val)
+    (let ((val (cond
+                ((list? val)
+                 (string-join (map maybe-object->string val) ";"))
+                ((or (string? val) (symbol? val))
+                 val)
+                (else (raise (formatted-message
+                              (G_ "\
+The value of an XDG MIME entry must be a list, string or symbol, was given ~a")
+                              val))))))
+      (format #f "~a=~a\n" key val)))
+
+  (define (merge-duplicates alist acc)
+    "Merge values that have the same key.
+
+@example
+(merge-duplicates '((key1 . value1)
+                      (key2 . value2)
+                      (key1 . value3)
+                      (key1 . value4)) '())
+
+@result{} ((key1 . (value4 value3 value1)) (key2 . value2))
+@end example"
+    (cond
+     ((null? alist) acc)
+     (else (let* ((head (first alist))
+                  (tail (cdr alist))
+                  (key (first head))
+                  (value (cdr head))
+                  (duplicate? (assoc key acc)))
+             (if duplicate?
+                 ;; XXX: This will change the order of things,
+                 ;; though, it shouldn't be a problem for XDG MIME.
+                 (merge-duplicates
+                  tail
+                  (alist-cons key
+                              (cons value (maybe-list (cdr duplicate?)))
+                              (alist-delete key acc)))
+                 (merge-duplicates tail (cons head acc)))))))
+
+  (string-append (if (equal? field-name 'default)
+                     "\n[Default Applications]\n"
+                     (format #f "\n[~a Associations]\n"
+                             (string-capitalize (symbol->string field-name))))
+                 (generic-serialize-alist string-append
+                                          serialize-mimelist-entry
+                                          (merge-duplicates val '()))))
+
+(define xdg-desktop-types (make-enumeration
+                           '(application
+                             link
+                             directory)))
+
+(define (xdg-desktop-type? type)
+  (unless (enum-set-member? type xdg-desktop-types)
+    (raise (formatted-message
+            (G_ "XDG desktop type must be of of ~a, was given: ~a")
+            (list->human-readable-list (enum-set->list xdg-desktop-types))
+            type))))
+
+;; TODO: Add proper docs for this
+;; XXX: 'define-configuration' require that fields have a default
+;; value.
+(define-record-type* <xdg-desktop-action>
+  xdg-desktop-action make-xdg-desktop-action
+  xdg-desktop-action?
+  (action xdg-desktop-action-action)  ; symbol
+  (name   xdg-desktop-action-name)    ; string
+  (config xdg-desktop-action-config   ; alist
+          (default '())))
+
+(define-record-type* <xdg-desktop-entry>
+  xdg-desktop-entry make-xdg-desktop-entry
+  xdg-desktop-entry?
+  ;; ".desktop" will automatically be added
+  (file    xdg-desktop-entry-file)    ; string
+  (name    xdg-desktop-entry-name)    ; string
+  (type    xdg-desktop-entry-type)    ; xdg-desktop-type
+  (config  xdg-desktop-entry-config   ; alist
+           (default '()))
+  (actions xdg-desktop-entry-actions  ; list of <xdg-desktop-action>
+           (default '())))
+
+(define desktop-entries? (list-of xdg-desktop-entry?))
+(define (serialize-desktop-entries field-name val) "")
+
+(define (serialize-xdg-desktop-entry entry)
+  "Return a tuple of the file name for ENTRY and the serialized
+configuration."
+  (define (format-config key val)
+    (let ((val (cond
+                ((list? val)
+                 (string-join (map maybe-object->string val) ";"))
+                ((boolean? val)
+                 (if val "true" "false"))
+                (else val)))
+          (key (string-capitalize (maybe-object->string key))))
+      (list (if (string-suffix? key "?")
+                (string-drop-right key (- (string-length key) 1))
+                key)
+            "=" val "\n")))
+
+  (define (serialize-alist config)
+    (generic-serialize-alist identity format-config config))
+
+  (define (serialize-xdg-desktop-action action)
+    (match action
+      (($ <xdg-desktop-action> action name config)
+       `(,(format #f "[Desktop Action ~a]\n"
+                  (string-capitalize (maybe-object->string action)))
+         ,(format #f "Name=~a\n" name)
+         ,@(serialize-alist config)))))
+
+  (match entry
+    (($ <xdg-desktop-entry> file name type config actions)
+     (list (if (string-suffix? file ".desktop")
+               file
+               (string-append file ".desktop"))
+           `("[Desktop Entry]\n"
+             ,(format #f "Name=~a\n" name)
+             ,(format #f "Type=~a\n"
+                      (string-capitalize (symbol->string type)))
+             ,@(serialize-alist config)
+             ,@(append-map serialize-xdg-desktop-action actions))))))
+
+(define-configuration home-xdg-mime-applications-configuration
+  (added
+   (alist '())
+   "An association list of MIME types and desktop entries which indicate
+that the application should used to open the specified MIME type.  The
+value has to be string, symbol, or list of strings or symbols, this
+applies to the `@code{default}', and `@code{removed}' fields as well.")
+  (default
+    (alist '())
+    "An association list of MIME types and desktop entries which indicate
+that the application should be the default for opening the specified
+MIME type.")
+  (removed
+   (alist '())
+   "An association list of MIME types and desktop entries which indicate
+that the application cannot open the specified MIME type.")
+  (desktop-entries
+   (desktop-entries '())
+   "A list of XDG desktop entries to create.  See
+@code{xdg-desktop-entry}."))
+
+(define (home-xdg-mime-applications-files-service config)
+  (define (add-xdg-desktop-entry-file entry)
+    (let ((file (first entry))
+          (config (second entry)))
+      (list (format #f "local/share/applications/~a" file)
+          (apply mixed-text-file
+                 (format #f "xdg-desktop-~a-entry" file)
+                 config))))
+
+  (append
+   `(("config/mimeapps.list"
+      ,(mixed-text-file
+        "xdg-mime-appplications"
+        (serialize-configuration
+         config
+         home-xdg-mime-applications-configuration-fields))))
+   (map (compose add-xdg-desktop-entry-file serialize-xdg-desktop-entry)
+        (home-xdg-mime-applications-configuration-desktop-entries config))))
+
+(define (home-xdg-mime-applications-extension old-config extension-configs)
+  (define (extract-fields config)
+    ;; return '(added default removed desktop-entries)
+    (list (home-xdg-mime-applications-configuration-added config)
+          (home-xdg-mime-applications-configuration-default config)
+          (home-xdg-mime-applications-configuration-removed config)
+          (home-xdg-mime-applications-configuration-desktop-entries config)))
+
+  (define (append-configs elem acc)
+    (list (append (first elem) (first acc))
+          (append (second elem) (second acc))
+          (append (third elem) (third acc))
+          (append (fourth elem) (fourth acc))))
+
+  ;; TODO: Implement procedure to check for duplicates without
+  ;; sacrificing performance.
+  ;;
+  ;; Combine all the alists from 'added', 'default' and 'removed'
+  ;; into one big alist.
+  (let ((folded-configs (fold append-configs
+                              (extract-fields old-config)
+                              (map extract-fields extension-configs))))
+    (home-xdg-mime-applications-configuration
+     (added (first folded-configs))
+     (default (second folded-configs))
+     (removed (third folded-configs))
+     (desktop-entries (fourth folded-configs)))))
+
+(define home-xdg-mime-applications-service-type
+  (service-type (name 'home-xdg-mime-applications)
+                (extensions
+                 (list (service-extension
+                        home-files-service-type
+                        home-xdg-mime-applications-files-service)))
+                (compose identity)
+                (extend home-xdg-mime-applications-extension)
+                (default-value (home-xdg-mime-applications-configuration))
+                (description
+                 "Configure XDG MIME applications, and XDG desktop entries.")))
diff --git a/gnu/home.scm b/gnu/home.scm
new file mode 100644
index 0000000000..f4c9359e25
--- /dev/null
+++ b/gnu/home.scm
@@ -0,0 +1,106 @@
+;;; GNU Guix --- Functional package management for GNU
+;;; Copyright © 2021 Andrew Tropin <andrew@trop.in>
+;;;
+;;; This file is part of GNU Guix.
+;;;
+;;; GNU Guix is free software; you can redistribute it and/or modify it
+;;; under the terms of the GNU General Public License as published by
+;;; the Free Software Foundation; either version 3 of the License, or (at
+;;; your option) any later version.
+;;;
+;;; GNU Guix is distributed in the hope that it will be useful, but
+;;; WITHOUT ANY WARRANTY; without even the implied warranty of
+;;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+;;; GNU General Public License for more details.
+;;;
+;;; You should have received a copy of the GNU General Public License
+;;; along with GNU Guix.  If not, see <http://www.gnu.org/licenses/>.
+
+(define-module (gnu home)
+  #:use-module (gnu home-services)
+  #:use-module (gnu home-services symlink-manager)
+  #:use-module (gnu home-services shells)
+  #:use-module (gnu home-services xdg)
+  #:use-module (gnu home-services fontutils)
+  #:use-module (gnu services)
+  #:use-module (guix records)
+  #:use-module (guix diagnostics)
+
+  #:export (home-environment
+            home-environment?
+            this-home-environment
+
+            home-environment-derivation
+            home-environment-user-services
+            home-environment-essential-services
+            home-environment-services
+            home-environment-location
+
+            home-environment-with-provenance))
+
+;;; Comment:
+;;;
+;;; This module provides a <home-environment> record for managing
+;;; per-user packages and configuration files in the similar way as
+;;; <operating-system> do for system packages and configuration files.
+;;;
+;;; Code:
+
+(define-record-type* <home-environment> home-environment
+  make-home-environment
+  home-environment?
+  this-home-environment
+
+  (packages           home-environment-packages            ; list of (PACKAGE OUTPUT...)
+                      (default '()))
+
+  (essential-services home-environment-essential-services  ; list of services
+                      (thunked)
+                      (default (home-environment-default-essential-services
+                                this-home-environment)))
+
+  (services           home-environment-user-services
+                      (default '()))
+
+  (location           home-environment-location            ; <location>
+                      (default (and=> (current-source-location)
+                                      source-properties->location))
+                      (innate)))
+
+(define (home-environment-default-essential-services he)
+  "Return the list of essential services for home environment."
+  (list
+   (service home-run-on-first-login-service-type)
+   (service home-activation-service-type)
+   (service home-environment-variables-service-type)
+
+   (service home-symlink-manager-service-type)
+
+   (service home-fontconfig-service-type)
+   (service home-xdg-base-directories-service-type)
+   (service home-shell-profile-service-type)
+
+   (service home-service-type)
+   (service home-profile-service-type (home-environment-packages he))))
+
+(define* (home-environment-services he)
+  "Return all the services of home environment."
+  (instantiate-missing-services
+   (append (home-environment-user-services he)
+           (home-environment-essential-services he))))
+
+(define* (home-environment-derivation he)
+  "Return a derivation that builds OS."
+  (let* ((services         (home-environment-services he))
+         (home (fold-services services
+                              #:target-type home-service-type)))
+    (service-value home)))
+
+(define* (home-environment-with-provenance he config-file)
+  "Return a variant of HE that stores its own provenance information,
+including CONFIG-FILE, if available.  This is achieved by adding an instance
+of HOME-PROVENANCE-SERVICE-TYPE to its services."
+  (home-environment
+    (inherit he)
+    (services (cons (service home-provenance-service-type config-file)
+                    (home-environment-user-services he)))))
diff --git a/gnu/local.mk b/gnu/local.mk
index b8ae060326..5bd7dced5e 100644
--- a/gnu/local.mk
+++ b/gnu/local.mk
@@ -44,6 +44,7 @@
 # Copyright © 2021 Arun Isaac <arunisaac@systemreboot.net>
 # Copyright © 2021 Sharlatan Hellseher <sharlatanus@gmail.com>
 # Copyright © 2021 Dmitry Polyakov <polyakov@liltechdude.xyz>
+# Copyright © 2021 Andrew Tropin <andrew@trop.in>
 #
 # This file is part of GNU Guix.
 #
@@ -72,6 +73,16 @@ GNU_SYSTEM_MODULES =				\
   %D%/bootloader/u-boot.scm                     \
   %D%/bootloader/depthcharge.scm                \
   %D%/ci.scm					\
+  %D%/home.scm					\
+  %D%/home-services.scm			\
+  %D%/home-services/symlink-manager.scm	\
+  %D%/home-services/fontutils.scm		\
+  %D%/home-services/configuration.scm		\
+  %D%/home-services/shells.scm			\
+  %D%/home-services/shepherd.scm		\
+  %D%/home-services/mcron.scm			\
+  %D%/home-services/utils.scm			\
+  %D%/home-services/xdg.scm			\
   %D%/image.scm					\
   %D%/packages.scm				\
   %D%/packages/abduco.scm			\
diff --git a/guix/scripts/home.scm b/guix/scripts/home.scm
new file mode 100644
index 0000000000..75df6d707d
--- /dev/null
+++ b/guix/scripts/home.scm
@@ -0,0 +1,512 @@
+;;; GNU Guix --- Functional package management for GNU
+;;; Copyright © 2021 Andrew Tropin <andrew@trop.in>
+;;; Copyright © 2021 Xinglu Chen <public@yoctocell.xyz>
+;;;
+;;; This file is part of GNU Guix.
+;;;
+;;; GNU Guix is free software; you can redistribute it and/or modify it
+;;; under the terms of the GNU General Public License as published by
+;;; the Free Software Foundation; either version 3 of the License, or (at
+;;; your option) any later version.
+;;;
+;;; GNU Guix is distributed in the hope that it will be useful, but
+;;; WITHOUT ANY WARRANTY; without even the implied warranty of
+;;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+;;; GNU General Public License for more details.
+;;;
+;;; You should have received a copy of the GNU General Public License
+;;; along with GNU Guix.  If not, see <http://www.gnu.org/licenses/>.
+
+(define-module (guix scripts home)
+  #:use-module (gnu packages admin)
+  #:use-module ((gnu services) #:hide (delete))
+  #:use-module (gnu packages)
+  #:use-module (gnu home)
+  #:use-module (gnu home-services)
+  #:use-module (guix channels)
+  #:use-module (guix derivations)
+  #:use-module (guix ui)
+  #:use-module (guix grafts)
+  #:use-module (guix packages)
+  #:use-module (guix profiles)
+  #:use-module (guix store)
+  #:use-module (guix utils)
+  #:use-module (guix scripts)
+  #:use-module (guix scripts package)
+  #:use-module (guix scripts build)
+  #:use-module (guix scripts system search)
+  #:autoload   (guix scripts pull) (channel-commit-hyperlink)
+  #:use-module (guix scripts home import)
+  #:use-module ((guix status) #:select (with-status-verbosity))
+  #:use-module (guix gexp)
+  #:use-module (guix monads)
+  #:use-module (srfi srfi-1)
+  #:use-module (srfi srfi-26)
+  #:use-module (srfi srfi-35)
+  #:use-module (srfi srfi-37)
+  #:use-module (ice-9 match)
+  #:export (guix-home))
+
+
+;;;
+;;; Options.
+;;;
+
+(define %user-module
+  (make-user-module '((gnu home))))
+
+(define %guix-home
+  (string-append %profile-directory "/guix-home"))
+
+(define (show-help)
+  (display (G_ "Usage: guix home [OPTION ...] ACTION [ARG ...] [FILE]
+Build the home environment declared in FILE according to ACTION.
+Some ACTIONS support additional ARGS.\n"))
+    (newline)
+  (display (G_ "The valid values for ACTION are:\n"))
+  (newline)
+  (display (G_ "\
+   search             search for existing service types\n"))
+  (display (G_ "\
+   reconfigure        switch to a new home environment configuration\n"))
+  (display (G_ "\
+   roll-back          switch to the previous home environment configuration\n"))
+  (display (G_ "\
+   describe           describe the current home environment\n"))
+  (display (G_ "\
+   list-generations   list the home environment generations\n"))
+  (display (G_ "\
+   switch-generation  switch to an existing home environment configuration\n"))
+  (display (G_ "\
+   delete-generations delete old home environment generations\n"))
+  (display (G_ "\
+   build              build the home environment without installing anything\n"))
+  (display (G_ "\
+   import             generates a home environment definition from dotfiles\n"))
+
+  (show-build-options-help)
+  (display (G_ "
+  -v, --verbosity=LEVEL  use the given verbosity LEVEL"))
+  (newline)
+  (display (G_ "
+  -h, --help             display this help and exit"))
+  (display (G_ "
+  -V, --version          display version information and exit"))
+  (newline)
+  (show-bug-report-information))
+
+(define (verbosity-level opts)
+  "Return the verbosity level based on OPTS, the alist of parsed options."
+  (or (assoc-ref opts 'verbosity)
+      (if (eq? (assoc-ref opts 'action) 'build)
+          2 1)))
+
+(define %options
+  ;; Specification of the command-line options.
+  (cons* (option '(#\h "help") #f #f
+                 (lambda args
+                   (show-help)
+                   (exit 0)))
+         (option '(#\V "version") #f #f
+                 (lambda args
+                   (show-version-and-exit "guix show")))
+         (option '(#\v "verbosity") #t #f
+                 (lambda (opt name arg result)
+                   (let ((level (string->number* arg)))
+                     (alist-cons 'verbosity level
+                                 (alist-delete 'verbosity result)))))
+         %standard-build-options))
+
+(define %default-options
+  `((build-mode . ,(build-mode normal))
+    (graft? . #t)
+    (substitutes? . #t)
+    (offload? . #t)
+    (print-build-trace? . #t)
+    (print-extended-build-trace? . #t)
+    (multiplexed-build-output? . #t)
+    (verbosity . 3)
+    (debug . 0)))
+
+
+;;;
+;;; Actions.
+;;;
+
+(define* (perform-action action he
+                         #:key
+                         dry-run?
+                         derivations-only?
+                         use-substitutes?)
+  "Perform ACTION for home environment. "
+
+  (define println
+    (cut format #t "~a~%" <>))
+
+  (mlet* %store-monad
+      ((he-drv   (home-environment-derivation he))
+       (drvs     (mapm/accumulate-builds lower-object (list he-drv)))
+       (%        (if derivations-only?
+                     (return
+                      (for-each (compose println derivation-file-name) drvs))
+                     (built-derivations drvs)))
+
+       (he-out-path -> (derivation->output-path he-drv)))
+    (if (or dry-run? derivations-only?)
+        (return #f)
+        (begin
+          (for-each (compose println derivation->output-path) drvs)
+
+          (case action
+            ((reconfigure)
+             (let* ((number (generation-number %guix-home))
+                    (generation (generation-file-name
+                                 %guix-home (+ 1 number))))
+
+               (switch-symlinks generation he-out-path)
+               (switch-symlinks %guix-home generation)
+               (setenv "GUIX_NEW_HOME" he-out-path)
+               (primitive-load (string-append he-out-path "/activate"))
+               (setenv "GUIX_NEW_HOME" #f)
+               (return he-out-path)))
+            (else
+             (newline)
+             (return he-out-path)))))))
+
+(define (process-action action args opts)
+  "Process ACTION, a sub-command, with the arguments are listed in ARGS.
+ACTION must be one of the sub-commands that takes a home environment
+declaration as an argument (a file name.)  OPTS is the raw alist of options
+resulting from command-line parsing."
+  (define (ensure-home-environment file-or-exp obj)
+    (unless (home-environment? obj)
+      (leave (G_ "'~a' does not return a home environment ~%")
+             file-or-exp))
+    obj)
+
+  (let* ((file   (match args
+                   (() #f)
+                   ((x . _) x)))
+         (expr   (assoc-ref opts 'expression))
+         (system (assoc-ref opts 'system))
+
+         (transform   (lambda (obj)
+                        (home-environment-with-provenance obj file)))
+
+         (home-environment
+          (transform
+           (ensure-home-environment
+            (or file expr)
+            (cond
+             ((and expr file)
+              (leave
+               (G_ "both file and expression cannot be specified~%")))
+             (expr
+              (read/eval expr))
+             (file
+              (load* file %user-module
+                     #:on-error (assoc-ref opts 'on-error)))
+             (else
+              (leave (G_ "no configuration specified~%")))))))
+
+         (dry?        (assoc-ref opts 'dry-run?)))
+
+    (with-store store
+      (set-build-options-from-command-line store opts)
+      (with-build-handler (build-notifier #:use-substitutes?
+                                          (assoc-ref opts 'substitutes?)
+                                          #:verbosity
+                                          (verbosity-level opts)
+                                          #:dry-run?
+                                          (assoc-ref opts 'dry-run?))
+
+        (run-with-store store
+          (mbegin %store-monad
+            (set-guile-for-build (default-guile))
+
+            (case action
+              (else
+               (perform-action action home-environment
+                               #:dry-run? dry?
+                               #:derivations-only? (assoc-ref opts 'derivations-only?)
+                               #:use-substitutes? (assoc-ref opts 'substitutes?))
+               ))))))
+    (warn-about-disk-space)))
+
+
+(define (process-command command args opts)
+  "Process COMMAND, one of the 'guix home' sub-commands.  ARGS is its
+argument list and OPTS is the option alist."
+  (define-syntax-rule (with-store* store exp ...)
+    (with-store store
+      (set-build-options-from-command-line store opts)
+      exp ...))
+  (case command
+    ;; The following commands do not need to use the store, and they do not need
+    ;; an home environment file.
+    ((search)
+     (apply search args))
+    ((import)
+     (let* ((profiles (delete-duplicates
+                      (match (filter-map (match-lambda
+                                           (('profile . p) p)
+                                           (_              #f))
+                                         opts)
+                        (() (list %current-profile))
+                        (lst (reverse lst)))))
+           (manifest (concatenate-manifests
+                      (map profile-manifest profiles))))
+       (import-manifest manifest (current-output-port))))
+    ((describe)
+     (match (generation-number %guix-home)
+       (0
+        (error (G_ "no home environment generation, nothing to describe~%")))
+       (generation
+        (display-home-environment-generation generation))))
+    ((list-generations)
+     (let ((pattern (match args
+                      (() #f)
+                      ((pattern) pattern)
+                      (x (leave (G_ "wrong number of arguments~%"))))))
+       (list-generations pattern)))
+    ((switch-generation)
+     (let ((pattern (match args
+                      ((pattern) pattern)
+                      (x (leave (G_ "wrong number of arguments~%"))))))
+       (with-store* store
+                    (switch-to-home-environment-generation store pattern))))
+    ((roll-back)
+     (let ((pattern (match args
+                      (() "")
+                      (x (leave (G_ "wrong number of arguments~%"))))))
+       (with-store* store
+                    (roll-back-home-environment store))))
+    ((delete-generations)
+     (let ((pattern (match args
+                      (() #f)
+                      ((pattern) pattern)
+                      (x (leave (G_ "wrong number of arguments~%"))))))
+       (with-store*
+        store
+        (delete-matching-generations store %guix-home pattern))))
+    (else (process-action command args opts))))
+
+(define-command (guix-home . args)
+  (synopsis "build and deploy home environments")
+
+  (define (parse-sub-command arg result)
+    ;; Parse sub-command ARG and augment RESULT accordingly.
+    (if (assoc-ref result 'action)
+        (alist-cons 'argument arg result)
+        (let ((action (string->symbol arg)))
+          (case action
+            ((build
+              reconfigure
+              extension-graph shepherd-graph
+              list-generations describe
+              delete-generations roll-back
+              switch-generation search
+              import)
+             (alist-cons 'action action result))
+            (else (leave (G_ "~a: unknown action~%") action))))))
+
+  (define (match-pair car)
+    ;; Return a procedure that matches a pair with CAR.
+    (match-lambda
+      ((head . tail)
+       (and (eq? car head) tail))
+      (_ #f)))
+
+  (define (option-arguments opts)
+    ;; Extract the plain arguments from OPTS.
+    (let* ((args   (reverse (filter-map (match-pair 'argument) opts)))
+           (count  (length args))
+           (action (assoc-ref opts 'action))
+           (expr   (assoc-ref opts 'expression)))
+      (define (fail)
+        (leave (G_ "wrong number of arguments for action '~a'~%")
+               action))
+
+      (unless action
+        (format (current-error-port)
+                (G_ "guix home: missing command name~%"))
+        (format (current-error-port)
+                (G_ "Try 'guix home --help' for more information.~%"))
+        (exit 1))
+
+      (case action
+        ((build reconfigure)
+         (unless (or (= count 1)
+                     (and expr (= count 0)))
+           (fail)))
+        ((init)
+         (unless (= count 2)
+           (fail))))
+      args))
+
+  (with-error-handling
+    (let* ((opts     (parse-command-line args %options
+                                         (list %default-options)
+                                         #:argument-handler
+                                         parse-sub-command))
+           (args     (option-arguments opts))
+           (command  (assoc-ref opts 'action)))
+      (parameterize ((%graft? (assoc-ref opts 'graft?)))
+        (with-status-verbosity (verbosity-level opts)
+          (process-command command args opts))))))
+
+
+;;;
+;;; Searching.
+;;;
+
+(define service-type-name*
+  (compose symbol->string service-type-name))
+
+(define (service-type-description-string type)
+  "Return the rendered and localised description of TYPE, a service type."
+  (and=> (service-type-description type)
+         (compose texi->plain-text P_)))
+
+(define %service-type-metrics
+  ;; Metrics used to estimate the relevance of a search result.
+  `((,service-type-name* . 3)
+    (,service-type-description-string . 2)
+    (,(lambda (type)
+        (match (and=> (service-type-location type) location-file)
+          ((? string? file)
+           (basename file ".scm"))
+          (#f
+           "")))
+     . 1)))
+
+(define (find-service-types regexps)
+  "Return a list of service type/score pairs: service types whose name or
+description matches REGEXPS sorted by relevance, and their score."
+  (let ((matches (fold-home-service-types
+                  (lambda (type result)
+                    (match (relevance type regexps
+                                      %service-type-metrics)
+                      ((? zero?)
+                       result)
+                      (score
+                       (cons (cons type score) result))))
+                  '())))
+    (sort matches
+          (lambda (m1 m2)
+            (match m1
+              ((type1 . score1)
+               (match m2
+                 ((type2 . score2)
+                  (if (= score1 score2)
+                      (string>? (service-type-name* type1)
+                                (service-type-name* type2))
+                      (> score1 score2))))))))))
+
+(define (search . args)
+  (with-error-handling
+    (let* ((regexps (map (cut make-regexp* <> regexp/icase) args))
+           (matches (find-service-types regexps)))
+      (leave-on-EPIPE
+       (display-search-results matches (current-output-port)
+                               #:print service-type->recutils
+                               #:command "guix home search")))))
+
+
+;;;
+;;; Generations.
+;;;
+
+(define* (display-home-environment-generation
+          number
+          #:optional (profile %guix-home))
+  "Display a summary of home-environment generation NUMBER in a
+human-readable format."
+  (define (display-channel channel)
+    (format #t     "    ~a:~%" (channel-name channel))
+    (format #t (G_ "      repository URL: ~a~%") (channel-url channel))
+    (when (channel-branch channel)
+      (format #t (G_ "      branch: ~a~%") (channel-branch channel)))
+    (format #t (G_ "      commit: ~a~%")
+            (if (supports-hyperlinks?)
+                (channel-commit-hyperlink channel)
+                (channel-commit channel))))
+
+  (unless (zero? number)
+    (let* ((generation  (generation-file-name profile number)))
+      (define-values (channels config-file)
+        ;; The function will work for home environments too, we just
+        ;; need to keep provenance file.
+        (system-provenance generation))
+
+      (display-generation profile number)
+      (format #t (G_ "  file name: ~a~%") generation)
+      (format #t (G_ "  canonical file name: ~a~%") (readlink* generation))
+      ;; TRANSLATORS: Please preserve the two-space indentation.
+
+      (unless (null? channels)
+        ;; TRANSLATORS: Here "channel" is the same terminology as used in
+        ;; "guix describe" and "guix pull --channels".
+        (format #t (G_ "  channels:~%"))
+        (for-each display-channel channels))
+      (when config-file
+        (format #t (G_ "  configuration file: ~a~%")
+                (if (supports-hyperlinks?)
+                    (file-hyperlink config-file)
+                    config-file))))))
+
+(define* (list-generations pattern #:optional (profile %guix-home))
+  "Display in a human-readable format all the home environment
+generations matching PATTERN, a string.  When PATTERN is #f, display
+all the home environment generations."
+  (cond ((not (file-exists? profile))             ; XXX: race condition
+         (raise (condition (&profile-not-found-error
+                            (profile profile)))))
+        ((not pattern)
+         (for-each display-home-environment-generation (profile-generations profile)))
+        ((matching-generations pattern profile)
+         =>
+         (lambda (numbers)
+           (if (null-list? numbers)
+               (exit 1)
+               (leave-on-EPIPE
+                (for-each display-home-environment-generation numbers)))))))
+
+
+;;;
+;;; Switch generations.
+;;;
+
+;; TODO: Make it public in (guix scripts system)
+(define-syntax-rule (unless-file-not-found exp)
+  (catch 'system-error
+    (lambda ()
+      exp)
+    (lambda args
+      (if (= ENOENT (system-error-errno args))
+          #f
+          (apply throw args)))))
+
+(define (switch-to-home-environment-generation store spec)
+  "Switch the home-environment profile to the generation specified by
+SPEC.  STORE is an open connection to the store."
+  (let* ((number (relative-generation-spec->number %guix-home spec))
+         (generation (generation-file-name %guix-home number))
+         (activate (string-append generation "/activate")))
+    (if number
+        (begin
+          (setenv "GUIX_NEW_HOME" (readlink generation))
+          (switch-to-generation* %guix-home number)
+          (unless-file-not-found (primitive-load activate))
+          (setenv "GUIX_NEW_HOME" #f))
+        (leave (G_ "cannot switch to home environment generation '~a'~%") spec))))
+
+
+;;;
+;;; Roll-back.
+;;;
+
+(define (roll-back-home-environment store)
+  "Roll back the home-environment profile to its previous generation.
+STORE is an open connection to the store."
+  (switch-to-home-environment-generation store "-1"))
diff --git a/guix/scripts/home/import.scm b/guix/scripts/home/import.scm
new file mode 100644
index 0000000000..39f45dbeac
--- /dev/null
+++ b/guix/scripts/home/import.scm
@@ -0,0 +1,241 @@
+;;; GNU Guix --- Functional package management for GNU
+;;; Copyright © 2021 Xinglu Chen <public@yoctocell.xyz>
+;;; Copyright © 2021 Andrew Tropin <andrew@trop.in>
+;;;
+;;; This file is part of GNU Guix.
+;;;
+;;; GNU Guix is free software; you can redistribute it and/or modify it
+;;; under the terms of the GNU General Public License as published by
+;;; the Free Software Foundation; either version 3 of the License, or (at
+;;; your option) any later version.
+;;;
+;;; GNU Guix is distributed in the hope that it will be useful, but
+;;; WITHOUT ANY WARRANTY; without even the implied warranty of
+;;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+;;; GNU General Public License for more details.
+;;;
+;;; You should have received a copy of the GNU General Public License
+;;; along with GNU Guix.  If not, see <http://www.gnu.org/licenses/>.
+
+(define-module (guix scripts home import)
+  #:use-module (guix profiles)
+  #:use-module (guix ui)
+  #:use-module (ice-9 match)
+  #:use-module (ice-9 pretty-print)
+  #:use-module (srfi srfi-1)
+  #:export (import-manifest))
+
+;;; Commentary:
+;;;
+;;; This module provides utilities for generating home service
+;;; configurations from existing "dotfiles".
+;;;
+;;; Code:
+
+
+(define (generate-bash-module+configuration)
+  (let ((rc (string-append (getenv "HOME") "/.bashrc"))
+        (profile (string-append (getenv "HOME") "/.bash_profile"))
+        (logout (string-append (getenv "HOME") "/.bash_logout")))
+    `((gnu home-services bash)
+      (service home-bash-service-type
+                 (home-bash-configuration
+                  ,@(if (file-exists? rc)
+                        `((bashrc
+                           (list (slurp-file-gexp (local-file ,rc)))))
+                        '())
+                  ,@(if (file-exists? profile)
+                        `((bash-profile
+                           (list (slurp-file-gexp
+                                  (local-file ,profile)))))
+                        '())
+                  ,@(if (file-exists? logout)
+                        `((bash-logout
+                           (list (slurp-file-gexp
+                                  (local-file ,logout)))))
+                        '()))))))
+
+
+(define %files-configurations-alist
+  `((".bashrc" . ,generate-bash-module+configuration)
+    (".bash_profile" . ,generate-bash-module+configuration)
+    (".bash_logout" . ,generate-bash-module+configuration)))
+
+(define (modules+configurations)
+  (let ((configurations (delete-duplicates
+                         (filter-map (match-lambda
+                                ((file . proc)
+                                 (if (file-exists?
+                                      (string-append (getenv "HOME") "/" file))
+                                     proc
+                                     #f)))
+                                     %files-configurations-alist)
+                         (lambda (x y)
+                           (equal? (procedure-name x) (procedure-name y))))))
+    (map (lambda (proc) (proc)) configurations)))
+
+;; Based on `manifest->code' from (guix profiles)
+;; MAYBE: Upstream it?
+(define* (manifest->code manifest
+                         #:key
+                         (entry-package-version (const ""))
+                         (home-environment? #f))
+  "Return an sexp representing code to build an approximate version of
+MANIFEST; the code is wrapped in a top-level 'begin' form.  If
+HOME-ENVIRONMENT? is #t, return an <home-environment> definition.
+Call ENTRY-PACKAGE-VERSION to determine the version number to use in
+the spec for a given entry; it can be set to 'manifest-entry-version'
+for fully-specified version numbers, or to some other procedure to
+disambiguate versions for packages for which several versions are
+available."
+  (define (entry-transformations entry)
+    ;; Return the transformations that apply to ENTRY.
+    (assoc-ref (manifest-entry-properties entry) 'transformations))
+
+  (define transformation-procedures
+    ;; List of transformation options/procedure name pairs.
+    (let loop ((entries (manifest-entries manifest))
+               (counter 1)
+               (result  '()))
+      (match entries
+        (() result)
+        ((entry . tail)
+         (match (entry-transformations entry)
+           (#f
+            (loop tail counter result))
+           (options
+            (if (assoc-ref result options)
+                (loop tail counter result)
+                (loop tail (+ 1 counter)
+                      (alist-cons options
+                                  (string->symbol
+                                   (format #f "transform~a" counter))
+                                  result)))))))))
+
+  (define (qualified-name entry)
+    ;; Return the name of ENTRY possibly with "@" followed by a version.
+    (match (entry-package-version entry)
+      (""      (manifest-entry-name entry))
+      (version (string-append (manifest-entry-name entry)
+                              "@" version))))
+
+  (if (null? transformation-procedures)
+      (let ((specs (map (lambda (entry)
+                          (match (manifest-entry-output entry)
+                            ("out"  (qualified-name entry))
+                            (output (string-append (qualified-name entry)
+                                                   ":" output))))
+                        (manifest-entries manifest))))
+        (if home-environment?
+            (let ((modules+configurations (modules+configurations)))
+              `(begin
+               (use-modules (gnu home)
+                            (gnu packages)
+                            ,@(map first modules+configurations))
+               ,(home-environment-template
+                 #:specs specs
+                 #:services (map second modules+configurations))))
+            `(begin
+               (use-modules (gnu packages))
+
+               (specifications->manifest
+                (list ,@specs)))))
+      (let* ((transform (lambda (options exp)
+                         (if (not options)
+                             exp
+                             (let ((proc (assoc-ref transformation-procedures
+                                                    options)))
+                               `(,proc ,exp)))))
+            (packages (map (lambda (entry)
+                                   (define options
+                                     (entry-transformations entry))
+
+                                   (define name
+                                     (qualified-name entry))
+
+                                   (match (manifest-entry-output entry)
+                                     ("out"
+                                      (transform options
+                                                 `(specification->package ,name)))
+                                     (output
+                                      `(list ,(transform
+                                               options
+                                               `(specification->package ,name))
+                                             ,output))))
+                           (manifest-entries manifest)))
+            (transformations (map (match-lambda
+                         ((options . name)
+                          `(define ,name
+                             (options->transformation ',options))))
+                       transformation-procedures)))
+        (if home-environment?
+            (let ((modules+configurations (modules+configurations)))
+              `(begin
+                 (use-modules (guix transformations)
+                              (gnu home)
+                              (gnu packages)
+                              ,@(map first modules+configurations))
+
+                 ,@transformations
+
+                 ,(home-environment-template
+                   #:packages packages
+                   #:services (map second modules+configurations))))
+            `(begin
+               (use-modules (guix transformations)
+                            (gnu packages))
+
+                ,@transformations
+
+                (packages->manifest
+                 (list ,@packages)))))))
+
+(define* (home-environment-template #:key (packages #f) (specs #f) services)
+  "Return an S-exp containing a <home-environment> declaration
+containing PACKAGES, or SPECS (package specifications), and SERVICES."
+  `(home-environment
+     (packages
+      ,@(if packages
+            `((list ,@packages))
+            `((map specification->package
+                   (list ,@specs)))))
+     (services (list ,@services))))
+
+(define* (import-manifest
+          manifest
+          #:optional (port (current-output-port)))
+  "Write to PORT a <home-environment> corresponding to MANIFEST."
+  (define (version-spec entry)
+    (let ((name (manifest-entry-name entry)))
+      (match (map package-version (find-packages-by-name name))
+        ((_)
+         ;; A single version of NAME is available, so do not specify the
+         ;; version number, even if the available version doesn't match ENTRY.
+         "")
+        (versions
+         ;; If ENTRY uses the latest version, don't specify any version.
+         ;; Otherwise return the shortest unique version prefix.  Note that
+         ;; this is based on the currently available packages, which could
+         ;; differ from the packages available in the revision that was used
+         ;; to build MANIFEST.
+         (let ((current (manifest-entry-version entry)))
+           (if (every (cut version>? current <>)
+                      (delete current versions))
+               ""
+               (version-unique-prefix (manifest-entry-version entry)
+                                      versions)))))))
+
+  (match (manifest->code manifest
+                         #:entry-package-version version-spec
+                         #:home-environment? #t)
+    (('begin exp ...)
+     (format port (G_ "\
+;; This \"home-environment\" file can be passed to 'guix home reconfigure'
+;; to reproduce the content of your profile.  This is \"symbolic\": it only
+;; specifies package names.  To reproduce the exact same profile, you also
+;; need to capture the channels being used, as returned by \"guix describe\".
+;; See the \"Replicating Guix\" section in the manual.\n"))
+     (for-each (lambda (exp)
+                 (newline port)
+                 (pretty-print exp port))
+               exp))))
diff --git a/guix/self.scm b/guix/self.scm
index 79d93357a2..5922ea6aa1 100644
--- a/guix/self.scm
+++ b/guix/self.scm
@@ -958,13 +958,23 @@ itself."
                  #:guile-for-build
                  guile-for-build))
 
+  (define *home-modules*
+    (scheme-node "guix-home"
+                 `((gnu home)
+                   (gnu home-services)
+                   ,@(scheme-modules* source "gnu/home-services"))
+                 (list *core-package-modules* *package-modules*
+                       *extra-modules* *core-modules* *system-modules*)
+                 #:extensions dependencies
+                 #:guile-for-build guile-for-build))
+
   (define *cli-modules*
     (scheme-node "guix-cli"
                  (append (scheme-modules* source "/guix/scripts")
                          `((gnu ci)))
                  (list *core-modules* *extra-modules*
                        *core-package-modules* *package-modules*
-                       *system-modules*)
+                       *system-modules* *home-modules*)
                  #:extensions dependencies
                  #:guile-for-build guile-for-build))
 
@@ -1012,6 +1022,7 @@ itself."
                                        *cli-modules*
                                        *system-test-modules*
                                        *system-modules*
+                                       *home-modules*
                                        *package-modules*
                                        *core-package-modules*
                                        *extra-modules*