diff --git a/gnu/build/shepherd.scm b/gnu/build/shepherd.scm
index 595db40f2e..d52e53eb78 100644
--- a/gnu/build/shepherd.scm
+++ b/gnu/build/shepherd.scm
@@ -1,6 +1,7 @@
 ;;; GNU Guix --- Functional package management for GNU
 ;;; Copyright © 2017, 2018, 2019, 2020, 2022 Ludovic Courtès <ludo@gnu.org>
 ;;; Copyright © 2020 Mathieu Othacehe <othacehe@gnu.org>
+;;; Copyright © 2022 Leo Nikkilä <hello@lnikki.la>
 ;;;
 ;;; This file is part of GNU Guix.
 ;;;
@@ -120,6 +121,7 @@ (define* (read-pid-file/container pid pid-file #:key (max-delay 5))
      pid)))
 
 (define* (exec-command* command #:key user group log-file pid-file
+                        (supplementary-groups '())
                         (directory "/") (environment-variables (environ)))
   "Like 'exec-command', but first restore signal handles modified by
 shepherd (PID 1)."
@@ -135,6 +137,7 @@ (define* (exec-command* command #:key user group log-file pid-file
   (exec-command command
                 #:user user
                 #:group group
+                #:supplementary-groups supplementary-groups
                 #:log-file log-file
                 #:directory directory
                 #:environment-variables environment-variables))
@@ -146,6 +149,7 @@ (define* (make-forkexec-constructor/container command
                                               (mappings '())
                                               (user #f)
                                               (group #f)
+                                              (supplementary-groups '())
                                               (log-file #f)
                                               pid-file
                                               (pid-file-timeout 5)
@@ -192,6 +196,8 @@ (define mounts
                                 (exec-command* command
                                                #:user user
                                                #:group group
+                                               #:supplementary-groups
+                                               supplementary-groups
                                                #:pid-file pid-file
                                                #:log-file log-file
                                                #:directory directory