diff --git a/common.mk b/common.mk
index fb65c88751..b376a32eaf 100644
--- a/common.mk
+++ b/common.mk
@@ -760,6 +760,7 @@ $(arch:noarch=ignore)-fake.rb: $(srcdir)/template/fake.rb.in $(tooldir)/generic_
 noarch-fake.rb: # prerequisite of yes-fake
 	$(Q) exit > $@
 
+# runner: BASERUBY, target: miniruby
 btest: $(TEST_RUNNABLE)-btest
 no-btest: PHONY
 yes-btest: yes-fake miniruby$(EXEEXT) PHONY
@@ -767,6 +768,7 @@ yes-btest: yes-fake miniruby$(EXEEXT) PHONY
 	$(Q)$(gnumake_recursive)$(exec) $(BOOTSTRAPRUBY) "$(srcdir)/bootstraptest/runner.rb" --ruby="$(BTESTRUBY) $(RUN_OPTS)" $(OPTS) $(TESTOPTS) $(BTESTS)
 	$(ACTIONS_ENDGROUP)
 
+# runner: ruby, target: ruby
 btest-ruby: $(TEST_RUNNABLE)-btest-ruby
 no-btest-ruby: PHONY
 yes-btest-ruby: prog PHONY
@@ -774,6 +776,12 @@ yes-btest-ruby: prog PHONY
 	$(Q)$(gnumake_recursive)$(exec) $(RUNRUBY) "$(srcdir)/bootstraptest/runner.rb" --ruby="$(PROGRAM) -I$(srcdir)/lib $(RUN_OPTS)" $(OPTS) $(TESTOPTS) $(BTESTS)
 	$(ACTIONS_ENDGROUP)
 
+# runner: BASERUBY, target: ruby
+btest-bruby: prog PHONY
+	$(ACTIONS_GROUP)
+	$(Q)$(gnumake_recursive)$(exec) $(BOOTSTRAPRUBY) "$(srcdir)/bootstraptest/runner.rb" --ruby="$(PROGRAM) -I$(srcdir)/lib $(RUN_OPTS)" $(OPTS) $(TESTOPTS) $(BTESTS)
+	$(ACTIONS_ENDGROUP)
+
 rtest: yes-fake miniruby$(EXEEXT) PHONY
 	$(ACTIONS_GROUP)
 	$(Q)$(exec) $(BOOTSTRAPRUBY) "$(srcdir)/bootstraptest/runner.rb" --ruby="$(BTESTRUBY) $(RUN_OPTS)" --sets=ractor -v