diff --git a/tests/guix-environment-container.sh b/tests/guix-environment-container.sh
index a3bc1ab572..09704f751c 100644
--- a/tests/guix-environment-container.sh
+++ b/tests/guix-environment-container.sh
@@ -270,5 +270,5 @@ guix build hello -d
 env="$(type -P pre-inst-env)"
 guix shell -C -D guix -- "$env" guix build hello -d && false # cannot work
 hello_drv="$(guix build hello -d)"
-hello_drv_nested="$(cd "$(dirname env)" && guix shell --bootstrap -CW -D guix -- "$env" guix build hello -d)"
+hello_drv_nested="$(cd "$(dirname env)" && guix shell --bootstrap -E GUIX_BUILD_OPTIONS -CW -D guix -- "$env" guix build hello -d)"
 test "$hello_drv" = "$hello_drv_nested"
diff --git a/tests/guix-pack.sh b/tests/guix-pack.sh
index 4042e54aeb..3204e821cf 100644
--- a/tests/guix-pack.sh
+++ b/tests/guix-pack.sh
@@ -30,7 +30,9 @@ fi
 guix pack --version
 
 # Use --no-substitutes because we need to verify we can do this ourselves.
-GUIX_BUILD_OPTIONS="--no-substitutes"
+# Use --no-grafts to avoid interference--e.g., --dry-run passing even when
+# given an unsupported package.
+GUIX_BUILD_OPTIONS="--no-substitutes --no-grafts"
 export GUIX_BUILD_OPTIONS
 
 test_directory="`mktemp -d`"
diff --git a/tests/transformations.scm b/tests/transformations.scm
index 704818b9ed..755211d65d 100644
--- a/tests/transformations.scm
+++ b/tests/transformations.scm
@@ -187,6 +187,11 @@ (define-module (test-transformations)
                       (string=? (package-full-name dep)
                                 (package-full-name findutils)))))))))))
 
+;; The following test requires grafting enabled, but it becomes extremely
+;; expensive if there's a graft on glibc or other package deep in the graph.
+(when (package-replacement (@ (gnu packages commencement) glibc-final))
+  (test-skip 1))
+
 (test-assert "options->transformation, with-graft"
   (let* ((p (dummy-package "guix.scm"
               (inputs `(("foo" ,grep)