diff --git a/.gitmodules b/.gitmodules
new file mode 100644
index 0000000000000000000000000000000000000000..d7ed45133f78840565854d5731c66d53a42823e5
--- /dev/null
+++ b/.gitmodules
@@ -0,0 +1,6 @@
+[submodule "external/mosquitto"]
+	path = external/mosquitto
+	url = https://gitee.com/cpp-master/mosquitto.git
+[submodule "external/json"]
+	path = external/json
+	url = https://gitee.com/cpp-master/json.git
diff --git a/Makefile b/Makefile
index 727af72198fd54b9a1e060e013f55a205aaad499..7e9995afa221256918ffd3c9e378389baa774c7c 100644
--- a/Makefile
+++ b/Makefile
@@ -1,6 +1,6 @@
 include build_env.mk
 
-.PHONY: all clean distclean
+.PHONY: all clean distclean depend
 
 CCFLAGS := -Wall
 
@@ -24,13 +24,23 @@ export CC CXX CFLAGS CXXFLAGS LDFLAGS APPS_DIR
 
 include config.mk
 
-all test:
+
+all test: depend
 	@for i in $(app_y); do \
 		[ ! -d $$i ] || $(MAKE) -C $$i $@ || exit $$? ; \
 	done
 
+depend:
+	@for i in $(depends_y); do \
+		[ ! -d $$i ] || $(MAKE) -C $$i || exit $$? ; \
+		[ ! -d $$i ] || $(MAKE) -C $$i install || exit $$? ; \
+	done
+
 clean:
 	-rm -rf $(OUTPUT_DIR)
 
 distclean: clean
+	@for i in $(depends_y); do \
+		[ ! -d $$i ] || $(MAKE) -C $$i $@ || exit $$? ; \
+	done
 	-rm -rf $(STAGING_DIR) $(INSTALL_DIR)
diff --git a/config.mk b/config.mk
index 7b1b536f02301510d65097dc58c6bc13febc44f2..570bfa1d838e191af109f0973e863a8e4bcd6bb0 100644
--- a/config.mk
+++ b/config.mk
@@ -1,3 +1,4 @@
+depends_y += external
 app_y += base
 app_y += util
 app_y += event
diff --git a/external/Makefile b/external/Makefile
new file mode 100644
index 0000000000000000000000000000000000000000..a1dfdcd2d1baf1d1111ceb2b1ea3cdb2dc163686
--- /dev/null
+++ b/external/Makefile
@@ -0,0 +1,19 @@
+HOST ?=
+Make ?= make -j$(shell nproc)
+
+.PHONY: all clean distclean install
+
+all:
+	$(Make) -C mosquitto || exit $$?
+
+clean distclean:
+	$(Make) -C mosquitto clean || exit $$?
+
+install: all
+	install -d $(STAGING_INCLUDE)/nlohmann
+	install -d $(STAGING_LIB)
+	install ./json/single_include/nlohmann/json.hpp $(STAGING_INCLUDE)/nlohmann/json.hpp
+	install ./json/include/nlohmann/json_fwd.hpp $(STAGING_INCLUDE)/nlohmann/json_fwd.hpp
+	make -C mosquitto install DESTDIR=$(STAGING_DIR)/mosquitto || exit $$?
+	cp -af $(STAGING_DIR)/mosquitto/usr/local/include/* $(STAGING_INCLUDE)
+	cp -af $(STAGING_DIR)/mosquitto/usr/local/lib/* $(STAGING_LIB)
diff --git a/external/json b/external/json
new file mode 160000
index 0000000000000000000000000000000000000000..db78ac1d7716f56fc9f1b030b715f872f93964e4
--- /dev/null
+++ b/external/json
@@ -0,0 +1 @@
+Subproject commit db78ac1d7716f56fc9f1b030b715f872f93964e4
diff --git a/external/mosquitto b/external/mosquitto
new file mode 160000
index 0000000000000000000000000000000000000000..02182aff6598319e64a56eea13241fb0fb985dd6
--- /dev/null
+++ b/external/mosquitto
@@ -0,0 +1 @@
+Subproject commit 02182aff6598319e64a56eea13241fb0fb985dd6