diff --git a/Makefile b/Makefile
index 3d11491f9..285b52c90 100644
--- a/Makefile
+++ b/Makefile
@@ -1,3 +1,8 @@
+ifeq ($(DEBUG),1)
+DEBUG_INFO = $(info $1)
+else
+DEBUG_INFO = @:
+endif
 REBAR = $(CURDIR)/rebar3
 BUILD = $(CURDIR)/build
 SCRIPTS = $(CURDIR)/scripts
@@ -23,10 +28,10 @@ export EMQX_EE_DASHBOARD_VERSION ?= e1.3.0
 # so the shell script will be executed tons of times.
 # https://github.com/emqx/emqx/pull/10627
 ifeq ($(strip $(OTP_VSN)),)
-	export OTP_VSN := $(shell $(SCRIPTS)/get-otp-vsn.sh)
+export OTP_VSN := $(shell $(SCRIPTS)/get-otp-vsn.sh)
 endif
 ifeq ($(strip $(ELIXIR_VSN)),)
-	export ELIXIR_VSN := $(shell $(SCRIPTS)/get-elixir-vsn.sh)
+export ELIXIR_VSN := $(shell $(SCRIPTS)/get-elixir-vsn.sh)
 endif
 
 PROFILE ?= emqx
@@ -101,31 +106,44 @@ static_checks:
 	./scripts/check-i18n-style.sh
 	./scripts/check_missing_reboot_apps.exs
 
-APPS=$(shell $(SCRIPTS)/find-apps.sh)
+# Allow user-set CASES environment variable
+ifneq ($(CASES),)
+CASES_ARG := --case $(CASES)
+endif
 
-.PHONY: $(APPS:%=%-ct)
+## example:
+## env SUITES=apps/appname/test/test_SUITE.erl CASES=t_foo make apps/appname-ct
 define gen-app-ct-target
 $1-ct: $(REBAR) merge-config clean-test-cluster-config
 	$(eval SUITES := $(shell $(SCRIPTS)/find-suites.sh $1))
 ifneq ($(SUITES),)
-		ENABLE_COVER_COMPILE=1 $(REBAR) ct -c -v \
-			--readable=$(CT_READABLE) \
-			--name $(CT_NODE_NAME) \
-			--cover_export_name $(CT_COVER_EXPORT_PREFIX)-$(subst /,-,$1) \
-			--suite $(SUITES)
+	ENABLE_COVER_COMPILE=1 $(REBAR) ct -c -v \
+		--readable=$(CT_READABLE) \
+		--name $(CT_NODE_NAME) \
+		--cover_export_name $(CT_COVER_EXPORT_PREFIX)-$(subst /,-,$1) \
+		--suite $(SUITES) \
+		$(CASES_ARG)
 else
-		@echo 'No suites found for $1'
+	@echo 'No suites found for $1'
 endif
 endef
-$(foreach app,$(APPS),$(eval $(call gen-app-ct-target,$(app))))
+
+ifneq ($(filter %-ct,$(MAKECMDGOALS)),)
+app_to_test := $(patsubst %-ct,%,$(filter %-ct,$(MAKECMDGOALS)))
+$(call DEBUG_INFO,app_to_test $(app_to_test))
+$(eval $(call gen-app-ct-target,$(app_to_test)))
+endif
 
 ## apps/name-prop targets
-.PHONY: $(APPS:%=%-prop)
 define gen-app-prop-target
 $1-prop:
 	$(REBAR) proper -d test/props -v -m $(shell $(SCRIPTS)/find-props.sh $1)
 endef
-$(foreach app,$(APPS),$(eval $(call gen-app-prop-target,$(app))))
+ifneq ($(filter %-prop,$(MAKECMDGOALS)),)
+app_to_test := $(patsubst %-prop,%,$(filter %-prop,$(MAKECMDGOALS)))
+$(call DEBUG_INFO,app_to_test $(app_to_test))
+$(eval $(call gen-app-prop-target,$(app_to_test)))
+endif
 
 .PHONY: ct-suite
 ct-suite: $(REBAR) merge-config clean-test-cluster-config
@@ -303,3 +321,7 @@ fmt: $(REBAR)
 .PHONY: clean-test-cluster-config
 clean-test-cluster-config:
 	@rm -f apps/emqx_conf/data/configs/cluster.hocon || true
+
+.PHONY: spellcheck
+spellcheck:
+	./scripts/spellcheck/spellcheck.sh _build/docgen/$(PROFILE)/schema-en.json
diff --git a/scripts/find-suites.sh b/scripts/find-suites.sh
index 47799f885..41b9b5e61 100755
--- a/scripts/find-suites.sh
+++ b/scripts/find-suites.sh
@@ -1,6 +1,6 @@
 #!/usr/bin/env bash
 
-## If EMQX_CT_SUITES is provided, it prints the variable.
+## If EMQX_CT_SUITES or SUITES is provided, it prints the variable.
 ## Otherwise this script tries to find all test/*_SUITE.erl files of then given app,
 ## file names are separated by comma for rebar3 ct's `--suite` option
 
@@ -12,7 +12,8 @@ set -euo pipefail
 # ensure dir
 cd -P -- "$(dirname -- "$0")/.."
 
-## EMQX_CT_SUITES is useful in ad-hoc runs
+## EMQX_CT_SUITES or SUITES is useful in ad-hoc runs
+EMQX_CT_SUITES="${EMQX_CT_SUITES:-${SUITES:-}}"
 if [ -n "${EMQX_CT_SUITES:-}" ]; then
     echo "${EMQX_CT_SUITES}"
     exit 0