diff --git a/operating-systems/buer.scm b/operating-systems/buer.scm
index 4ba89c9..b000fd2 100644
--- a/operating-systems/buer.scm
+++ b/operating-systems/buer.scm
@@ -1,7 +1,8 @@
-#|Modules|#
 (define-module (radix operating-systems buer)
   #|GNU|#
   #:use-module (gnu)
+  #:use-module ((gnu system) #:select (operating-system)
+                             #:prefix gnu:)
 
   #|GNU packages|#
   #|A|# #:use-module (gnu packages admin)
@@ -54,268 +55,270 @@
   #|S|# #:use-module ((radix files substitute-keys) #:prefix public-key:)
   #|T|# #:use-module ((radix files thinkfan)        #:prefix file:thinkfan-))
 
-#|Operating system definition|#
-(operating-system
- (host-name "buer")
- (timezone "America/Sao_Paulo")
- (locale "en_US.utf8")
+(define operating-system
+  (gnu:operating-system
+   (host-name "buer")
+   (timezone "America/Sao_Paulo")
+   (locale "en_US.utf8")
 
- (keyboard-layout
-  (keyboard-layout "us,br"
-                   #:options `("grp:menu_switch"
-                               "parens:swap_brackets"
-                               "caps:swapescape")))
+   (keyboard-layout
+    (keyboard-layout "us,br"
+                     #:options `("grp:menu_switch"
+                                 "parens:swap_brackets"
+                                 "caps:swapescape")))
 
- (bootloader
-  (bootloader-configuration
-   (bootloader grub-bootloader)
-   (targets `("/dev/sda"))
-   (timeout 1)
-   (theme (grub-theme
-           (image (file-append %artwork-repository
-                               "/backgrounds/guix-silver-16-9.svg"))
-           (gfxmode `("1280x720x32"))))))
+   (bootloader
+    (bootloader-configuration
+     (bootloader grub-bootloader)
+     (targets `("/dev/sda"))
+     (timeout 1)
+     (theme (grub-theme
+             (image (file-append %artwork-repository
+                                 "/backgrounds/guix-silver-16-9.svg"))
+             (gfxmode `("1280x720x32"))))))
 
- (kernel-arguments
-  `("modprobe.blacklist=usbmouse,usbkbd,pcspkr"
-    "thinkpad_acpi.fan_control=1"
-    "loglevel=5"
-    "quiet"))
+   (kernel-arguments
+    `("modprobe.blacklist=usbmouse,usbkbd,pcspkr"
+      "thinkpad_acpi.fan_control=1"
+      "loglevel=5"
+      "quiet"))
 
- (file-systems
-  (cons* (file-system
-          (device (file-system-label "guix-root"))
-          (mount-point "/")
-          (type "ext4"))
-         (file-system
-          (device (file-system-label "home"))
-          (mount-point "/home")
-          (type "ext4"))
-         %base-file-systems))
+   (file-systems
+    (cons* (file-system
+            (device (file-system-label "guix-root"))
+            (mount-point "/")
+            (type "ext4"))
+           (file-system
+            (device (file-system-label "home"))
+            (mount-point "/home")
+            (type "ext4"))
+           %base-file-systems))
 
- (users
-  (cons* (user-account
-          (name "radio")
-          (password %radio-password)
-          (home-directory "/home/radio")
-          (shell (file-append dash-next "/bin/dash"))
-          (uid 1000)
-          (group "users")
-          (supplementary-groups `("audio" "adbusers" "video" "wheel")))
-         (user-account
-          (name "root")
-          (password %root-password)
-          (system? #t)
-          (home-directory "/root")
-          (uid 0)
-          (group "root")
-          (shell (file-append dash-next "/bin/dash")))
-         %base-user-accounts))
+   (users
+    (cons* (user-account
+            (name "radio")
+            (password %radio-password)
+            (home-directory "/home/radio")
+            (shell (file-append dash-next "/bin/dash"))
+            (uid 1000)
+            (group "users")
+            (supplementary-groups `("audio" "adbusers" "video" "wheel")))
+           (user-account
+            (name "root")
+            (password %root-password)
+            (system? #t)
+            (home-directory "/root")
+            (uid 0)
+            (group "root")
+            (shell (file-append dash-next "/bin/dash")))
+           %base-user-accounts))
 
- (groups
-  (cons* (user-group
-           (name "adbusers"))
-         %base-groups))
+   (groups
+    (cons* (user-group
+             (name "adbusers"))
+           %base-groups))
 
- #|System level packages|#
- (packages
-  (list #|admin       |# btop inetutils isc-dhcp opendoas shadow zzz
-        #|base        |# coreutils diffutils findutils grep patch sed tar which
-        #|certs       |# nss-certs
-        #|compression |# bzip2 gzip lzip unzip xz zstd
-        #|gawk        |# gawk
-        #|guile       |# guile-3.0-latest guile-colorized guile-readline
-        #|less        |# less
-        #|linux       |# e2fsprogs eudev iproute kmod procps psmisc util-linux
-        #|man         |# man-db mandoc man-pages
-        #|shells      |# dash-next
-        #|texinfo     |# info-reader
-        #|text-editors|# kakoune-git
-        #|vpn         |# wireguard-tools))
+   #|System level packages|#
+   (packages
+    (list #|admin       |# btop inetutils isc-dhcp opendoas shadow zzz
+          #|base        |# coreutils diffutils findutils grep patch sed tar which
+          #|certs       |# nss-certs
+          #|compression |# bzip2 gzip lzip unzip xz zstd
+          #|gawk        |# gawk
+          #|guile       |# guile-3.0-latest guile-colorized guile-readline
+          #|less        |# less
+          #|linux       |# e2fsprogs eudev iproute kmod procps psmisc util-linux
+          #|man         |# man-db mandoc man-pages
+          #|shells      |# dash-next
+          #|texinfo     |# info-reader
+          #|text-editors|# kakoune-git
+          #|vpn         |# wireguard-tools))
 
- #|Do not generate a sudoers file|#
- (sudoers-file #f)
+   #|Do not generate a sudoers file|#
+   (sudoers-file #f)
 
- #|Run some programs from each package with file owner privileges|#
- (setuid-programs
-  (map-setuid-programs
-    (shadow     `("passwd" "chfn" "sg" "su" "newgrp" "newuidmap" "newgidmap"))
-    (inetutils  `("ping" "ping6"))
-    (opendoas   `("doas"))
-    (fuse-2     `("fusermount"))
-    (fuse       `("fusermount3"))
-    (util-linux `("mount" "umount"))))
+   #|Run some programs from each package with file owner privileges|#
+   (setuid-programs
+    (map-setuid-programs
+      (shadow     `("passwd" "chfn" "sg" "su" "newgrp" "newuidmap" "newgidmap"))
+      (inetutils  `("ping" "ping6"))
+      (opendoas   `("doas"))
+      (fuse-2     `("fusermount"))
+      (fuse       `("fusermount3"))
+      (util-linux `("mount" "umount"))))
 
- #|Allow resolution of '.local' host names with mDNS|#
- (name-service-switch %mdns-host-lookup-nss)
+   #|Allow resolution of '.local' host names with mDNS|#
+   (name-service-switch %mdns-host-lookup-nss)
 
- #|System services|#
- (services
-  (list #|TTY services|#
-        (service virtual-terminal-service-type)
-        (service console-font-service-type
-                 (associate-right
-                  (%default-console-font `("tty1" "tty2"))))
-        (service agetty-service-type
-                 (agetty-configuration
-                  (extra-options `("-L"))
-                  (term "vt100")
-                  (tty #f)))
-        (service mingetty-service-type
-                 (mingetty-configuration (tty "tty1")))
-        (service mingetty-service-type
-                 (mingetty-configuration (tty "tty2")))
+   #|System services|#
+   (services
+    (list #|TTY services|#
+          (service virtual-terminal-service-type)
+          (service console-font-service-type
+                   (associate-right
+                    (%default-console-font `("tty1" "tty2"))))
+          (service agetty-service-type
+                   (agetty-configuration
+                    (extra-options `("-L"))
+                    (term "vt100")
+                    (tty #f)))
+          (service mingetty-service-type
+                   (mingetty-configuration (tty "tty1")))
+          (service mingetty-service-type
+                   (mingetty-configuration (tty "tty2")))
 
-        #|Login services|#
-        (service login-service-type)
-        (service elogind-service-type)
+          #|Login services|#
+          (service login-service-type)
+          (service elogind-service-type)
 
-        #|Log services|#
-        (service rottlog-service-type)
-        (service syslog-service-type
-                 (syslog-configuration
-                  (syslogd (file-append inetutils "/libexec/syslogd"))
-                  (config-file %default-syslog.conf)))
-        (service log-cleanup-service-type
-                 (log-cleanup-configuration
-                  (directory "/var/log/guix/drvs")
-                  (expiry (* 3 30 24 3600))))
+          #|Log services|#
+          (service rottlog-service-type)
+          (service syslog-service-type
+                   (syslog-configuration
+                    (syslogd (file-append inetutils "/libexec/syslogd"))
+                    (config-file %default-syslog.conf)))
+          (service log-cleanup-service-type
+                   (log-cleanup-configuration
+                    (directory "/var/log/guix/drvs")
+                    (expiry (* 3 30 24 3600))))
 
-        #|IPC services|#
-        (service dbus-root-service-type)
+          #|IPC services|#
+          (service dbus-root-service-type)
 
-        #|Avahi service|#
-        (service avahi-service-type
-                 (avahi-configuration
-                  (wide-area? #t)))
+          #|Avahi service|#
+          (service avahi-service-type
+                   (avahi-configuration
+                    (wide-area? #t)))
 
-        #|Guix services|#
-        (service guix-service-type
-                 (guix-configuration
-                  (discover? #t)
-                  (build-accounts 16)
-                  (authorized-keys
-                   (cons* public-key:yuria
-                          %default-authorized-guix-keys))
-                  (extra-options `("--max-jobs=8" "--cores=4"))))
-        (service guix-publish-service-type
-                 (guix-publish-configuration
-                  (port 8080)
-                  (host "0.0.0.0")
-                  (advertise? #t)
-                  (compression `(("zstd" 3)))))
+          #|Guix services|#
+          (service guix-service-type
+                   (guix-configuration
+                    (discover? #t)
+                    (build-accounts 16)
+                    (authorized-keys
+                     (cons* public-key:yuria
+                            %default-authorized-guix-keys))
+                    (extra-options `("--max-jobs=8" "--cores=4"))))
+          (service guix-publish-service-type
+                   (guix-publish-configuration
+                    (port 8080)
+                    (host "0.0.0.0")
+                    (advertise? #t)
+                    (compression `(("zstd" 3)))))
 
-        #|Mcron service|#
-        (simple-service 'mcron-jobs mcron-service-type
-                        (list #~(job "5 0 * * *"
-                                     "guix gc --optimize --free-space=5G")))
+          #|Mcron service|#
+          (simple-service 'mcron-jobs mcron-service-type
+                          (list #~(job "5 0 * * *"
+                                       "guix gc --optimize --free-space=5G")))
 
-        #|Device management services|#
-        (service udev-service-type
-                 (udev-configuration
-                  (udev eudev)
-                  (rules (list alsa-utils
-                               android-udev-rules
-                               crda
-                               fuse
-                               lvm2))))
+          #|Device management services|#
+          (service udev-service-type
+                   (udev-configuration
+                    (udev eudev)
+                    (rules (list alsa-utils
+                                 android-udev-rules
+                                 crda
+                                 fuse
+                                 lvm2))))
 
-        #|Network services|#
-        (service static-networking-service-type
-                 (list (static-networking
-                        (addresses
-                         (list (network-address
-                                (device "lo")
-                                (value "127.0.0.1/8"))))
-                        (provision '(loopback)))))
-        (service ntp-service-type)
-        (service wpa-supplicant-service-type
-                 (wpa-supplicant-configuration
-                  (config-file "/etc/wpa_supplicant.conf")
-                  (interface "wlp2s0")
-                  (extra-options `("-B"))))
-        (service dhcp-client-service-type
-                 (dhcp-client-configuration
-                  (interfaces 'all)))
-        (service tor-service-type)
+          #|Network services|#
+          (service static-networking-service-type
+                   (list (static-networking
+                          (addresses
+                           (list (network-address
+                                  (device "lo")
+                                  (value "127.0.0.1/8"))))
+                          (provision '(loopback)))))
+          (service ntp-service-type)
+          (service wpa-supplicant-service-type
+                   (wpa-supplicant-configuration
+                    (config-file "/etc/wpa_supplicant.conf")
+                    (interface "wlp2s0")
+                    (extra-options `("-B"))))
+          (service dhcp-client-service-type
+                   (dhcp-client-configuration
+                    (interfaces 'all)))
+          (service tor-service-type)
 
-        #|Power management services|#
-        (service tlp-service-type
-                 (tlp-configuration
-                  (cpu-scaling-governor-on-ac  `("performance"))
-                  (cpu-scaling-governor-on-bat `("powersave"))
-                  (cpu-scaling-min-freq-on-ac  1500000)
-                  (cpu-scaling-max-freq-on-ac  3500000)
-                  (cpu-scaling-min-freq-on-bat 1000000)
-                  (cpu-scaling-max-freq-on-bat 3000000)
-                  (cpu-min-perf-on-ac    0)
-                  (cpu-max-perf-on-ac  100)
-                  (cpu-min-perf-on-bat   0)
-                  (cpu-max-perf-on-bat  40)
-                  (cpu-boost-on-ac?  #t)
-                  (cpu-boost-on-bat? #f)
-                  (nmi-watchdog? #t)
-                  (start-charge-thresh-bat0 70)
-                  (stop-charge-thresh-bat0  90)))
-        (service thinkfan-service-type
-                 (thinkfan-configuration
-                  (thinkfan thinkfan-next)
-                  (config-file file:thinkfan-config)))
-        (service thermald-service-type)
+          #|Power management services|#
+          (service tlp-service-type
+                   (tlp-configuration
+                    (cpu-scaling-governor-on-ac  `("performance"))
+                    (cpu-scaling-governor-on-bat `("powersave"))
+                    (cpu-scaling-min-freq-on-ac  1500000)
+                    (cpu-scaling-max-freq-on-ac  3500000)
+                    (cpu-scaling-min-freq-on-bat 1000000)
+                    (cpu-scaling-max-freq-on-bat 3000000)
+                    (cpu-min-perf-on-ac    0)
+                    (cpu-max-perf-on-ac  100)
+                    (cpu-min-perf-on-bat   0)
+                    (cpu-max-perf-on-bat  40)
+                    (cpu-boost-on-ac?  #t)
+                    (cpu-boost-on-bat? #f)
+                    (nmi-watchdog? #t)
+                    (start-charge-thresh-bat0 70)
+                    (stop-charge-thresh-bat0  90)))
+          (service thinkfan-service-type
+                   (thinkfan-configuration
+                    (thinkfan thinkfan-next)
+                    (config-file file:thinkfan-config)))
+          (service thermald-service-type)
 
-        #|Memory management services|#
-        (service zram-device-service-type
-                 (zram-device-configuration
-                  (size "2G")
-                  (compression-algorithm 'zstd)))
+          #|Memory management services|#
+          (service zram-device-service-type
+                   (zram-device-configuration
+                    (size "2G")
+                    (compression-algorithm 'zstd)))
 
-        #|Doas configuration services|#
-        (simple-service 'miscellaneous-permissions doas-service-type
-                        (list (permit (identity ":wheel")
-                                      (setenv `(("GUILE_LOAD_PATH" . #t))))
-                              (permit (identity ":wheel")
-                                      (nopass? #t)
-                                      (command "guix")
-                                      (args `("pull")))))
-        (simple-service 'text-editors-permissions doas-service-type
-                        (map (lambda (cmd)
-                               (permit (identity ":wheel")
-                                       (keepenv? #t)
-                                       (command cmd)))
-                             `("kak" "emacsclient")))
-        (simple-service 'power-management-permissions doas-service-type
-                        (map (lambda (cmd)
-                               (permit (identity ":wheel")
-                                       (nopass? #t)
-                                       (command cmd)
-                                       (args '())))
-                             `("zzz" "halt" "reboot")))
-        (simple-service 'shepherd-status-permissions doas-service-type
-                        (map (lambda (action)
-                               (permit (identity ":wheel")
-                                       (nopass? #t)
-                                       (command "herd")
-                                       (args (list action))))
-                             `("status" "detailed-status")))
-        (simple-service 'service-management-permissions doas-service-type
-                        (flat-map (lambda (service action)
-                                    (permit (identity ":wheel")
-                                            (nopass? #t)
-                                            (command "herd")
-                                            (args (map symbol->string
-                                                       (list action service)))))
-                                  '(tor networking wpa-supplicant)
-                                  '(doc stop start enable status restart disable)))
-        #|Special file services|#
-        (service special-files-service-type
-                 `(("/bin/sh"      ,(file-append dash-next "/bin/dash"))
-                   ("/usr/bin/env" ,(file-append coreutils "/bin/env"))))
+          #|Doas configuration services|#
+          (simple-service 'miscellaneous-permissions doas-service-type
+                          (list (permit (identity ":wheel")
+                                        (setenv `(("GUILE_LOAD_PATH" . #t))))
+                                (permit (identity ":wheel")
+                                        (nopass? #t)
+                                        (command "guix")
+                                        (args `("pull")))))
+          (simple-service 'text-editors-permissions doas-service-type
+                          (map (lambda (cmd)
+                                 (permit (identity ":wheel")
+                                         (keepenv? #t)
+                                         (command cmd)))
+                               `("kak" "emacsclient")))
+          (simple-service 'power-management-permissions doas-service-type
+                          (map (lambda (cmd)
+                                 (permit (identity ":wheel")
+                                         (nopass? #t)
+                                         (command cmd)
+                                         (args '())))
+                               `("zzz" "halt" "reboot")))
+          (simple-service 'shepherd-status-permissions doas-service-type
+                          (map (lambda (action)
+                                 (permit (identity ":wheel")
+                                         (nopass? #t)
+                                         (command "herd")
+                                         (args (list action))))
+                               `("status" "detailed-status")))
+          (simple-service 'service-management-permissions doas-service-type
+                          (flat-map (lambda (service action)
+                                      (permit (identity ":wheel")
+                                              (nopass? #t)
+                                              (command "herd")
+                                              (args (map symbol->string
+                                                         (list action service)))))
+                                    '(tor networking wpa-supplicant)
+                                    '(doc stop start enable status restart disable)))
+          #|Special file services|#
+          (service special-files-service-type
+                   `(("/bin/sh"      ,(file-append dash-next "/bin/dash"))
+                     ("/usr/bin/env" ,(file-append coreutils "/bin/env"))))
 
-        #|Miscellaneous services|#
-        (service urandom-seed-service-type)
-        (service nscd-service-type)
-        (service sysctl-service-type
-                 (sysctl-configuration
-                  (sysctl (file-append procps "/sbin/sysctl"))
-                  (settings `(("fs.protected_hardlinks" . "1")
-                              ("fs.protected_symlinks"  . "1"))))))))
+          #|Miscellaneous services|#
+          (service urandom-seed-service-type)
+          (service nscd-service-type)
+          (service sysctl-service-type
+                   (sysctl-configuration
+                    (sysctl (file-append procps "/sbin/sysctl"))
+                    (settings `(("fs.protected_hardlinks" . "1")
+                                ("fs.protected_symlinks"  . "1")))))))))
+
+operating-system