diff --git a/gnu/build/image.scm b/gnu/build/image.scm
index 53c75839ba..dbb87103da 100644
--- a/gnu/build/image.scm
+++ b/gnu/build/image.scm
@@ -83,7 +83,8 @@ turn doesn't take any constant overhead into account, force a 1-MiB minimum."
         (label (partition-label partition))
         (uuid (partition-uuid partition)))
     (apply invoke
-           `("fakeroot" "mkfs.btrfs" "-r" ,root
+           `("unshare" "--map-root-user" "mkfs.btrfs"
+             "-r" ,root
              "-L" ,label
              ,@(if uuid
                    `("-U" ,(uuid->string uuid))
diff --git a/gnu/system/image.scm b/gnu/system/image.scm
index 73686023a9..ac0706aa0f 100644
--- a/gnu/system/image.scm
+++ b/gnu/system/image.scm
@@ -504,7 +504,7 @@ used in the image."
                                       initialize-root-partition))
                      (inputs '#+(cond
                                   ((string=? type "btrfs")
-                                   (list btrfs-progs fakeroot))
+                                   (list btrfs-progs util-linux))
                                   ((string-prefix? "ext" type)
                                    (list e2fsprogs fakeroot))
                                   ((string=? type "f2fs")