diff --git a/apps/mosquitto_ctrl/CMakeLists.txt b/apps/mosquitto_ctrl/CMakeLists.txt
index 6d241cfb..dd6ba27f 100644
--- a/apps/mosquitto_ctrl/CMakeLists.txt
+++ b/apps/mosquitto_ctrl/CMakeLists.txt
@@ -41,14 +41,14 @@ if(WITH_TLS AND CJSON_FOUND)
 	endif()
 
 	if(WITH_STATIC_LIBRARIES)
-		target_link_libraries(mosquitto_ctrl libmosquitto_static)
+		target_link_libraries(mosquitto_ctrl PRIVATE libmosquitto_static)
 	else()
-		target_link_libraries(mosquitto_ctrl libmosquitto)
+		target_link_libraries(mosquitto_ctrl PRIVATE libmosquitto)
 	endif()
 
 	if(UNIX)
 		if(APPLE)
-			target_link_libraries(mosquitto_ctrl dl)
+			target_link_libraries(mosquitto_ctrl PRIVATE dl)
 		elseif(${CMAKE_SYSTEM_NAME} MATCHES "OpenBSD")
 			#
 		elseif(${CMAKE_SYSTEM_NAME} MATCHES "NetBSD")
@@ -56,11 +56,12 @@ if(WITH_TLS AND CJSON_FOUND)
 		elseif(QNX)
 			#
 		else()
-			target_link_libraries(mosquitto_ctrl dl)
+			target_link_libraries(mosquitto_ctrl PRIVATE dl)
 		endif()
 	endif()
 
 	target_link_libraries(mosquitto_ctrl
+	  PRIVATE
 		${OPENSSL_LIBRARIES}
 		${CJSON_LIBRARIES}
 	)
diff --git a/apps/mosquitto_passwd/CMakeLists.txt b/apps/mosquitto_passwd/CMakeLists.txt
index 42198c46..75120186 100644
--- a/apps/mosquitto_passwd/CMakeLists.txt
+++ b/apps/mosquitto_passwd/CMakeLists.txt
@@ -20,7 +20,8 @@ if(WITH_TLS)
 		"${mosquitto_SOURCE_DIR}/src"
 	)
 
-	target_link_libraries(mosquitto_passwd
+    target_link_libraries(mosquitto_passwd
+	  PRIVATE
 		${OPENSSL_LIBRARIES}
 	)
 
diff --git a/plugins/dynamic-security/CMakeLists.txt b/plugins/dynamic-security/CMakeLists.txt
index 6f726186..f5804f1a 100644
--- a/plugins/dynamic-security/CMakeLists.txt
+++ b/plugins/dynamic-security/CMakeLists.txt
@@ -57,9 +57,9 @@ if(CJSON_FOUND AND WITH_TLS)
 		POSITION_INDEPENDENT_CODE 1
 	)
 
-	target_link_libraries(mosquitto_dynamic_security ${CJSON_LIBRARIES} ${OPENSSL_LIBRARIES})
+	target_link_libraries(mosquitto_dynamic_security PRIVATE ${CJSON_LIBRARIES} ${OPENSSL_LIBRARIES})
 	if(WIN32)
-		target_link_libraries(mosquitto_dynamic_security mosquitto)
+		target_link_libraries(mosquitto_dynamic_security PRIVATE mosquitto)
 		install(TARGETS mosquitto_dynamic_security
 			DESTINATION "${CMAKE_INSTALL_BINDIR}")
 	else()
diff --git a/plugins/examples/add-properties/CMakeLists.txt b/plugins/examples/add-properties/CMakeLists.txt
index 585cfb49..88f7e4dd 100644
--- a/plugins/examples/add-properties/CMakeLists.txt
+++ b/plugins/examples/add-properties/CMakeLists.txt
@@ -17,7 +17,7 @@ set_target_properties(${PLUGIN_NAME} PROPERTIES
 )
 
 if(WIN32)
-	target_link_libraries(${PLUGIN_NAME} mosquitto)
+	target_link_libraries(${PLUGIN_NAME} PRIVATE mosquitto)
 endif()
 
 # Don't install, these are example plugins only.
diff --git a/plugins/examples/auth-by-ip/CMakeLists.txt b/plugins/examples/auth-by-ip/CMakeLists.txt
index 8daa18b5..23390bdf 100644
--- a/plugins/examples/auth-by-ip/CMakeLists.txt
+++ b/plugins/examples/auth-by-ip/CMakeLists.txt
@@ -17,7 +17,7 @@ set_target_properties(${PLUGIN_NAME} PROPERTIES
 )
 
 if(WIN32)
-	target_link_libraries(${PLUGIN_NAME} mosquitto)
+	target_link_libraries(${PLUGIN_NAME} PRIVATE mosquitto)
 endif()
 
 # Don't install, these are example plugins only.
diff --git a/plugins/examples/client-lifetime-stats/CMakeLists.txt b/plugins/examples/client-lifetime-stats/CMakeLists.txt
index 80459a0b..ddabc98b 100644
--- a/plugins/examples/client-lifetime-stats/CMakeLists.txt
+++ b/plugins/examples/client-lifetime-stats/CMakeLists.txt
@@ -20,7 +20,7 @@ set_target_properties(${PLUGIN_NAME} PROPERTIES
 	POSITION_INDEPENDENT_CODE 1
 )
 if(WIN32)
-	target_link_libraries(${PLUGIN_NAME} mosquitto)
+	target_link_libraries(${PLUGIN_NAME} PRIVATE mosquitto)
 endif()
 
 # Don't install, these are example plugins only.
diff --git a/plugins/examples/client-properties/CMakeLists.txt b/plugins/examples/client-properties/CMakeLists.txt
index 9459a0b5..39121881 100644
--- a/plugins/examples/client-properties/CMakeLists.txt
+++ b/plugins/examples/client-properties/CMakeLists.txt
@@ -19,7 +19,7 @@ set_target_properties(${PLUGIN_NAME} PROPERTIES
 )
 
 if(WIN32)
-	target_link_libraries(${PLUGIN_NAME} mosquitto)
+	target_link_libraries(${PLUGIN_NAME} PRIVATE mosquitto)
 endif()
 
 # Don't install, these are example plugins only.
diff --git a/plugins/examples/connection-state/CMakeLists.txt b/plugins/examples/connection-state/CMakeLists.txt
index f7613556..b2cc2a46 100644
--- a/plugins/examples/connection-state/CMakeLists.txt
+++ b/plugins/examples/connection-state/CMakeLists.txt
@@ -17,7 +17,7 @@ set_target_properties(${PLUGIN_NAME} PROPERTIES
 )
 
 if(WIN32)
-	target_link_libraries(${PLUGIN_NAME} mosquitto)
+	target_link_libraries(${PLUGIN_NAME} PRIVATE mosquitto)
 endif()
 
 # Don't install, these are example plugins only.
diff --git a/plugins/examples/delayed-auth/CMakeLists.txt b/plugins/examples/delayed-auth/CMakeLists.txt
index b16c24bf..e2811968 100644
--- a/plugins/examples/delayed-auth/CMakeLists.txt
+++ b/plugins/examples/delayed-auth/CMakeLists.txt
@@ -23,7 +23,7 @@ set_target_properties(${PLUGIN_NAME} PROPERTIES
 )
 
 if(WIN32)
-	target_link_libraries(${PLUGIN_NAME} mosquitto)
+	target_link_libraries(${PLUGIN_NAME} PRIVATE mosquitto)
 endif()
 
 # Don't install, these are example plugins only.
diff --git a/plugins/examples/force-retain/CMakeLists.txt b/plugins/examples/force-retain/CMakeLists.txt
index a55b6dcd..b8984c65 100644
--- a/plugins/examples/force-retain/CMakeLists.txt
+++ b/plugins/examples/force-retain/CMakeLists.txt
@@ -19,7 +19,7 @@ set_target_properties(${PLUGIN_NAME} PROPERTIES
 	POSITION_INDEPENDENT_CODE 1
 )
 if(WIN32)
-	target_link_libraries(${PLUGIN_NAME} mosquitto)
+	target_link_libraries(${PLUGIN_NAME} PRIVATE mosquitto)
 endif()
 
 # Don't install, these are example plugins only.
diff --git a/plugins/examples/message-timestamp/CMakeLists.txt b/plugins/examples/message-timestamp/CMakeLists.txt
index 4363d10c..e40f528c 100644
--- a/plugins/examples/message-timestamp/CMakeLists.txt
+++ b/plugins/examples/message-timestamp/CMakeLists.txt
@@ -18,7 +18,7 @@ set_target_properties(${PLUGIN_NAME} PROPERTIES
 )
 
 if(WIN32)
-	target_link_libraries(${PLUGIN_NAME} mosquitto)
+	target_link_libraries(${PLUGIN_NAME} PRIVATE mosquitto)
 endif()
 
 # Don't install, these are example plugins only.
diff --git a/plugins/examples/payload-modification/CMakeLists.txt b/plugins/examples/payload-modification/CMakeLists.txt
index 9c67373c..dbeaa4dc 100644
--- a/plugins/examples/payload-modification/CMakeLists.txt
+++ b/plugins/examples/payload-modification/CMakeLists.txt
@@ -19,7 +19,7 @@ set_target_properties(${PLUGIN_NAME} PROPERTIES
 	POSITION_INDEPENDENT_CODE 1
 )
 if(WIN32)
-	target_link_libraries(${PLUGIN_NAME} mosquitto)
+	target_link_libraries(${PLUGIN_NAME} PRIVATE mosquitto)
 endif()
 
 # Don't install, these are example plugins only.
diff --git a/plugins/examples/payload-size-stats/CMakeLists.txt b/plugins/examples/payload-size-stats/CMakeLists.txt
index 112964b1..f504f52b 100644
--- a/plugins/examples/payload-size-stats/CMakeLists.txt
+++ b/plugins/examples/payload-size-stats/CMakeLists.txt
@@ -19,7 +19,7 @@ set_target_properties(${PLUGIN_NAME} PROPERTIES
 	POSITION_INDEPENDENT_CODE 1
 )
 if(WIN32)
-	target_link_libraries(${PLUGIN_NAME} mosquitto)
+	target_link_libraries(${PLUGIN_NAME} PRIVATE mosquitto)
 endif()
 
 # Don't install, these are example plugins only.
diff --git a/plugins/examples/plugin-event-stats/CMakeLists.txt b/plugins/examples/plugin-event-stats/CMakeLists.txt
index 7f22c923..d12adce8 100644
--- a/plugins/examples/plugin-event-stats/CMakeLists.txt
+++ b/plugins/examples/plugin-event-stats/CMakeLists.txt
@@ -19,7 +19,7 @@ set_target_properties(${PLUGIN_NAME} PROPERTIES
 	POSITION_INDEPENDENT_CODE 1
 )
 if(WIN32)
-	target_link_libraries(${PLUGIN_NAME} mosquitto)
+	target_link_libraries(${PLUGIN_NAME} PRIVATE mosquitto)
 endif()
 
 # Don't install, these are example plugins only.
diff --git a/plugins/examples/print-ip-on-publish/CMakeLists.txt b/plugins/examples/print-ip-on-publish/CMakeLists.txt
index bdedc9ff..2528f75e 100644
--- a/plugins/examples/print-ip-on-publish/CMakeLists.txt
+++ b/plugins/examples/print-ip-on-publish/CMakeLists.txt
@@ -19,7 +19,7 @@ set_target_properties(${PLUGIN_NAME} PROPERTIES
 	POSITION_INDEPENDENT_CODE 1
 )
 if(WIN32)
-	target_link_libraries(${PLUGIN_NAME} mosquitto)
+	target_link_libraries(${PLUGIN_NAME} PRIVATE mosquitto)
 endif()
 
 # Don't install, these are example plugins only.
diff --git a/plugins/examples/topic-modification/CMakeLists.txt b/plugins/examples/topic-modification/CMakeLists.txt
index 5f6e7aad..361d7433 100644
--- a/plugins/examples/topic-modification/CMakeLists.txt
+++ b/plugins/examples/topic-modification/CMakeLists.txt
@@ -19,7 +19,7 @@ set_target_properties(${PLUGIN_NAME} PROPERTIES
 	POSITION_INDEPENDENT_CODE 1
 )
 if(WIN32)
-	target_link_libraries(${PLUGIN_NAME} mosquitto)
+	target_link_libraries(${PLUGIN_NAME} PRIVATE mosquitto)
 endif()
 
 # Don't install, these are example plugins only.
diff --git a/plugins/examples/wildcard-temp/CMakeLists.txt b/plugins/examples/wildcard-temp/CMakeLists.txt
index bed2ccf0..9e74e568 100644
--- a/plugins/examples/wildcard-temp/CMakeLists.txt
+++ b/plugins/examples/wildcard-temp/CMakeLists.txt
@@ -24,7 +24,7 @@ set_target_properties(${PLUGIN_NAME} PROPERTIES
 )
 
 if(WIN32)
-	target_link_libraries(${PLUGIN_NAME} mosquitto)
+	target_link_libraries(${PLUGIN_NAME} PRIVATE mosquitto)
 endif()
 
 # Don't install, these are example plugins only.
diff --git a/plugins/persist-sqlite/CMakeLists.txt b/plugins/persist-sqlite/CMakeLists.txt
index 17d39858..c53db27f 100644
--- a/plugins/persist-sqlite/CMakeLists.txt
+++ b/plugins/persist-sqlite/CMakeLists.txt
@@ -34,9 +34,9 @@ if(SQLITE3_FOUND AND CJSON_FOUND)
 		POSITION_INDEPENDENT_CODE 1
 	)
 
-	target_link_libraries(mosquitto_persist_sqlite ${SQLITE3_LIBRARIES})
+	target_link_libraries(mosquitto_persist_sqlite PRIVATE ${SQLITE3_LIBRARIES})
 	if(WIN32)
-		target_link_libraries(mosquitto_persist_sqlite mosquitto)
+		target_link_libraries(mosquitto_persist_sqlite PRIVATE mosquitto)
 	endif()
 
 	install(TARGETS mosquitto_persist_sqlite
diff --git a/src/CMakeLists.txt b/src/CMakeLists.txt
index eaf7cec3..c053fb5c 100644
--- a/src/CMakeLists.txt
+++ b/src/CMakeLists.txt
@@ -47,7 +47,9 @@ set (MOSQ_SRCS
 	plugin_init.c plugin_cleanup.c plugin_persist.c
 	plugin_acl_check.c plugin_basic_auth.c plugin_connect.c plugin_disconnect.c
 	plugin_extended_auth.c plugin_message.c plugin_psk_key.c plugin_public.c
+	plugin_subscribe.c
 	plugin_tick.c
+	plugin_unsubscribe.c
 	property_broker.c
 	../lib/property_mosq.c ../lib/property_mosq.h
 	read_handle.c
@@ -237,6 +239,7 @@ if(WITH_BUNDLED_DEPS)
 endif()
 
 target_link_libraries(mosquitto
+  PRIVATE
 	${MOSQ_LIBS}
 )