diff --git a/maxscale-system-test/maxtest/include/maxtest/appexception.h b/maxscale-system-test/maxtest/include/maxtest/appexception.hh
similarity index 100%
rename from maxscale-system-test/maxtest/include/maxtest/appexception.h
rename to maxscale-system-test/maxtest/include/maxtest/appexception.hh
diff --git a/maxscale-system-test/maxtest/include/maxtest/clustrix_nodes.h b/maxscale-system-test/maxtest/include/maxtest/clustrix_nodes.h
index f2549d28c..6ba775cb1 100644
--- a/maxscale-system-test/maxtest/include/maxtest/clustrix_nodes.h
+++ b/maxscale-system-test/maxtest/include/maxtest/clustrix_nodes.h
@@ -23,7 +23,7 @@
 
 #include <errno.h>
 #include <string>
-#include "nodes.h"
+#include "nodes.hh"
 #include "mariadb_nodes.h"
 
 #define CLUSTRIX_DEPS_YUM "yum install -y bzip2 wget screen ntp ntpdate vim htop mdadm"
diff --git a/maxscale-system-test/maxtest/include/maxtest/env.h b/maxscale-system-test/maxtest/include/maxtest/env.hh
similarity index 100%
rename from maxscale-system-test/maxtest/include/maxtest/env.h
rename to maxscale-system-test/maxtest/include/maxtest/env.hh
diff --git a/maxscale-system-test/maxtest/include/maxtest/envv.h b/maxscale-system-test/maxtest/include/maxtest/envv.hh
similarity index 100%
rename from maxscale-system-test/maxtest/include/maxtest/envv.h
rename to maxscale-system-test/maxtest/include/maxtest/envv.hh
diff --git a/maxscale-system-test/maxtest/include/maxtest/execute_cmd.h b/maxscale-system-test/maxtest/include/maxtest/execute_cmd.hh
similarity index 100%
rename from maxscale-system-test/maxtest/include/maxtest/execute_cmd.h
rename to maxscale-system-test/maxtest/include/maxtest/execute_cmd.hh
diff --git a/maxscale-system-test/maxtest/include/maxtest/mariadb_nodes.h b/maxscale-system-test/maxtest/include/maxtest/mariadb_nodes.h
index e9b45b282..4da3db711 100644
--- a/maxscale-system-test/maxtest/include/maxtest/mariadb_nodes.h
+++ b/maxscale-system-test/maxtest/include/maxtest/mariadb_nodes.h
@@ -16,7 +16,7 @@
 #include "mariadb_func.h"
 #include <errno.h>
 #include <string>
-#include "nodes.h"
+#include "nodes.hh"
 
 /**
  * @brief A class to handle backend nodes
diff --git a/maxscale-system-test/maxtest/include/maxtest/maxscales.h b/maxscale-system-test/maxtest/include/maxtest/maxscales.hh
similarity index 99%
rename from maxscale-system-test/maxtest/include/maxtest/maxscales.h
rename to maxscale-system-test/maxtest/include/maxtest/maxscales.hh
index d3b28f97f..ec012d771 100644
--- a/maxscale-system-test/maxtest/include/maxtest/maxscales.h
+++ b/maxscale-system-test/maxtest/include/maxtest/maxscales.hh
@@ -1,7 +1,7 @@
 #pragma once
 
 #include <string>
-#include "nodes.h"
+#include "nodes.hh"
 #include "mariadb_func.h"
 #include "mariadb_nodes.h"
 
diff --git a/maxscale-system-test/maxtest/include/maxtest/nodes.h b/maxscale-system-test/maxtest/include/maxtest/nodes.hh
similarity index 100%
rename from maxscale-system-test/maxtest/include/maxtest/nodes.h
rename to maxscale-system-test/maxtest/include/maxtest/nodes.hh
diff --git a/maxscale-system-test/maxtest/include/maxtest/stopwatch.h b/maxscale-system-test/maxtest/include/maxtest/stopwatch.hh
similarity index 100%
rename from maxscale-system-test/maxtest/include/maxtest/stopwatch.h
rename to maxscale-system-test/maxtest/include/maxtest/stopwatch.hh
diff --git a/maxscale-system-test/maxtest/include/maxtest/tcp_connection.h b/maxscale-system-test/maxtest/include/maxtest/tcp_connection.hh
similarity index 100%
rename from maxscale-system-test/maxtest/include/maxtest/tcp_connection.h
rename to maxscale-system-test/maxtest/include/maxtest/tcp_connection.hh
diff --git a/maxscale-system-test/maxtest/include/maxtest/testconnections.h b/maxscale-system-test/maxtest/include/maxtest/testconnections.h
index 584123899..ff5701f9b 100644
--- a/maxscale-system-test/maxtest/include/maxtest/testconnections.h
+++ b/maxscale-system-test/maxtest/include/maxtest/testconnections.h
@@ -2,7 +2,7 @@
 
 #include "mariadb_nodes.h"
 #include "clustrix_nodes.h"
-#include "maxscales.h"
+#include "maxscales.hh"
 #include "test_dir.hh"
 #include <fcntl.h>
 #include <pthread.h>
diff --git a/maxscale-system-test/maxtest/src/CMakeLists.txt b/maxscale-system-test/maxtest/src/CMakeLists.txt
index 7b2ae34e0..b7d62176c 100644
--- a/maxscale-system-test/maxtest/src/CMakeLists.txt
+++ b/maxscale-system-test/maxtest/src/CMakeLists.txt
@@ -1,29 +1,29 @@
 add_library(maxtest SHARED
-        big_load.cpp
-        big_transaction.cpp
-        blob_test.cpp
+        big_load.cc
+        big_transaction.cc
+        blob_test.cc
         clustrix_nodes.cpp
-        config_operations.cpp
-        different_size.cpp
-        envv.cpp
-        execute_cmd.cpp
-        fw_copy_rules.cpp
-        get_com_select_insert.cpp
-        get_my_ip.cpp
-        keepalived_func.cpp
-        mariadb_func.cpp
-        mariadb_nodes.cpp
-        maxadmin_operations.cpp
-        maxinfo_func.cpp
+        config_operations.cc
+        different_size.cc
+        envv.cc
+        execute_cmd.cc
+        fw_copy_rules.cc
+        get_com_select_insert.cc
+        get_my_ip.cc
+        keepalived_func.cc
+        mariadb_func.cc
+        mariadb_nodes.cc
+        maxadmin_operations.cc
+        maxinfo_func.cc
         maxrest.cc
-        maxscales.cpp
-        nodes.cpp
-        rds_vpc.cpp
-        sql_t1.cpp
-        stopwatch.cpp
-        tcp_connection.cpp
-        test_binlog_fnc.cpp
-        testconnections.cpp
+        maxscales.cc
+        nodes.cc
+        rds_vpc.cc
+        sql_t1.cc
+        stopwatch.cc
+        tcp_connection.cc
+        test_binlog_fnc.cc
+        testconnections.cc
         ${CMAKE_CURRENT_BINARY_DIR}/test_info.cc
         # Include the CDC connector in the core library
         ${CMAKE_SOURCE_DIR}/connectors/cdc-connector/cdc_connector.cpp)
diff --git a/maxscale-system-test/maxtest/src/big_load.cpp b/maxscale-system-test/maxtest/src/big_load.cc
similarity index 100%
rename from maxscale-system-test/maxtest/src/big_load.cpp
rename to maxscale-system-test/maxtest/src/big_load.cc
diff --git a/maxscale-system-test/maxtest/src/big_transaction.cpp b/maxscale-system-test/maxtest/src/big_transaction.cc
similarity index 100%
rename from maxscale-system-test/maxtest/src/big_transaction.cpp
rename to maxscale-system-test/maxtest/src/big_transaction.cc
diff --git a/maxscale-system-test/maxtest/src/blob_test.cpp b/maxscale-system-test/maxtest/src/blob_test.cc
similarity index 100%
rename from maxscale-system-test/maxtest/src/blob_test.cpp
rename to maxscale-system-test/maxtest/src/blob_test.cc
diff --git a/maxscale-system-test/maxtest/src/config_operations.cpp b/maxscale-system-test/maxtest/src/config_operations.cc
similarity index 100%
rename from maxscale-system-test/maxtest/src/config_operations.cpp
rename to maxscale-system-test/maxtest/src/config_operations.cc
diff --git a/maxscale-system-test/maxtest/src/different_size.cpp b/maxscale-system-test/maxtest/src/different_size.cc
similarity index 100%
rename from maxscale-system-test/maxtest/src/different_size.cpp
rename to maxscale-system-test/maxtest/src/different_size.cc
diff --git a/maxscale-system-test/maxtest/src/envv.cpp b/maxscale-system-test/maxtest/src/envv.cc
similarity index 99%
rename from maxscale-system-test/maxtest/src/envv.cpp
rename to maxscale-system-test/maxtest/src/envv.cc
index 0b6ab355d..70560633f 100644
--- a/maxscale-system-test/maxtest/src/envv.cpp
+++ b/maxscale-system-test/maxtest/src/envv.cc
@@ -1,4 +1,4 @@
-#include "envv.h"
+#include "envv.hh"
 
 #include <cstring>
 #include <cstdarg>
diff --git a/maxscale-system-test/maxtest/src/execute_cmd.cpp b/maxscale-system-test/maxtest/src/execute_cmd.cc
similarity index 96%
rename from maxscale-system-test/maxtest/src/execute_cmd.cpp
rename to maxscale-system-test/maxtest/src/execute_cmd.cc
index d6aa7555f..68c85a49b 100644
--- a/maxscale-system-test/maxtest/src/execute_cmd.cpp
+++ b/maxscale-system-test/maxtest/src/execute_cmd.cc
@@ -3,7 +3,7 @@
 #include <stdio.h>
 #include <string.h>
 #include <errno.h>
-#include "execute_cmd.h"
+#include "execute_cmd.hh"
 
 using namespace std;
 
diff --git a/maxscale-system-test/maxtest/src/fw_copy_rules.cpp b/maxscale-system-test/maxtest/src/fw_copy_rules.cc
similarity index 100%
rename from maxscale-system-test/maxtest/src/fw_copy_rules.cpp
rename to maxscale-system-test/maxtest/src/fw_copy_rules.cc
diff --git a/maxscale-system-test/maxtest/src/get_com_select_insert.cpp b/maxscale-system-test/maxtest/src/get_com_select_insert.cc
similarity index 100%
rename from maxscale-system-test/maxtest/src/get_com_select_insert.cpp
rename to maxscale-system-test/maxtest/src/get_com_select_insert.cc
diff --git a/maxscale-system-test/maxtest/src/get_my_ip.cpp b/maxscale-system-test/maxtest/src/get_my_ip.cc
similarity index 100%
rename from maxscale-system-test/maxtest/src/get_my_ip.cpp
rename to maxscale-system-test/maxtest/src/get_my_ip.cc
diff --git a/maxscale-system-test/maxtest/src/keepalived_func.cpp b/maxscale-system-test/maxtest/src/keepalived_func.cc
similarity index 100%
rename from maxscale-system-test/maxtest/src/keepalived_func.cpp
rename to maxscale-system-test/maxtest/src/keepalived_func.cc
diff --git a/maxscale-system-test/maxtest/src/mariadb_func.cpp b/maxscale-system-test/maxtest/src/mariadb_func.cc
similarity index 100%
rename from maxscale-system-test/maxtest/src/mariadb_func.cpp
rename to maxscale-system-test/maxtest/src/mariadb_func.cc
diff --git a/maxscale-system-test/maxtest/src/mariadb_nodes.cpp b/maxscale-system-test/maxtest/src/mariadb_nodes.cc
similarity index 99%
rename from maxscale-system-test/maxtest/src/mariadb_nodes.cpp
rename to maxscale-system-test/maxtest/src/mariadb_nodes.cc
index 6abd69483..d6a83fe0f 100644
--- a/maxscale-system-test/maxtest/src/mariadb_nodes.cpp
+++ b/maxscale-system-test/maxtest/src/mariadb_nodes.cc
@@ -20,7 +20,7 @@
 #include <future>
 #include <functional>
 #include <algorithm>
-#include "envv.h"
+#include "envv.hh"
 
 using std::cout;
 using std::endl;
diff --git a/maxscale-system-test/maxtest/src/maxadmin_operations.cpp b/maxscale-system-test/maxtest/src/maxadmin_operations.cc
similarity index 100%
rename from maxscale-system-test/maxtest/src/maxadmin_operations.cpp
rename to maxscale-system-test/maxtest/src/maxadmin_operations.cc
diff --git a/maxscale-system-test/maxtest/src/maxinfo_func.cpp b/maxscale-system-test/maxtest/src/maxinfo_func.cc
similarity index 100%
rename from maxscale-system-test/maxtest/src/maxinfo_func.cpp
rename to maxscale-system-test/maxtest/src/maxinfo_func.cc
diff --git a/maxscale-system-test/maxtest/src/maxscales.cpp b/maxscale-system-test/maxtest/src/maxscales.cc
similarity index 99%
rename from maxscale-system-test/maxtest/src/maxscales.cpp
rename to maxscale-system-test/maxtest/src/maxscales.cc
index 255fafbe9..c9ae3b271 100644
--- a/maxscale-system-test/maxtest/src/maxscales.cpp
+++ b/maxscale-system-test/maxtest/src/maxscales.cc
@@ -1,8 +1,8 @@
-#include "maxscales.h"
+#include "maxscales.hh"
 #include <sstream>
 #include <unordered_map>
 #include <string>
-#include "envv.h"
+#include "envv.hh"
 
 Maxscales::Maxscales(const char *pref,
                      const char *test_cwd,
diff --git a/maxscale-system-test/maxtest/src/nodes.cpp b/maxscale-system-test/maxtest/src/nodes.cc
similarity index 99%
rename from maxscale-system-test/maxtest/src/nodes.cpp
rename to maxscale-system-test/maxtest/src/nodes.cc
index ceba742ef..210af899b 100644
--- a/maxscale-system-test/maxtest/src/nodes.cpp
+++ b/maxscale-system-test/maxtest/src/nodes.cc
@@ -1,4 +1,4 @@
-#include "nodes.h"
+#include "nodes.hh"
 #include <string>
 #include <cstring>
 #include <iostream>
@@ -7,7 +7,7 @@
 #include <algorithm>
 #include <signal.h>
 
-#include "envv.h"
+#include "envv.hh"
 
 Nodes::Nodes(const char* pref,
              const std::string& network_config,
diff --git a/maxscale-system-test/maxtest/src/rds_vpc.cpp b/maxscale-system-test/maxtest/src/rds_vpc.cc
similarity index 99%
rename from maxscale-system-test/maxtest/src/rds_vpc.cpp
rename to maxscale-system-test/maxtest/src/rds_vpc.cc
index 6d51575f4..62ac3d3cc 100644
--- a/maxscale-system-test/maxtest/src/rds_vpc.cpp
+++ b/maxscale-system-test/maxtest/src/rds_vpc.cc
@@ -1,4 +1,4 @@
-#include "execute_cmd.h"
+#include "execute_cmd.hh"
 #include "rds_vpc.h"
 
 RDS::RDS(char* cluster)
diff --git a/maxscale-system-test/maxtest/src/sql_t1.cpp b/maxscale-system-test/maxtest/src/sql_t1.cc
similarity index 100%
rename from maxscale-system-test/maxtest/src/sql_t1.cpp
rename to maxscale-system-test/maxtest/src/sql_t1.cc
diff --git a/maxscale-system-test/maxtest/src/stopwatch.cpp b/maxscale-system-test/maxtest/src/stopwatch.cc
similarity index 99%
rename from maxscale-system-test/maxtest/src/stopwatch.cpp
rename to maxscale-system-test/maxtest/src/stopwatch.cc
index ae40b9fee..cc4563d72 100644
--- a/maxscale-system-test/maxtest/src/stopwatch.cpp
+++ b/maxscale-system-test/maxtest/src/stopwatch.cc
@@ -11,7 +11,7 @@
  * Public License.
  */
 
-#include "stopwatch.h"
+#include "stopwatch.hh"
 
 #include <iomanip>
 #include <iostream>
diff --git a/maxscale-system-test/maxtest/src/tcp_connection.cpp b/maxscale-system-test/maxtest/src/tcp_connection.cc
similarity index 98%
rename from maxscale-system-test/maxtest/src/tcp_connection.cpp
rename to maxscale-system-test/maxtest/src/tcp_connection.cc
index cc0227ea9..88b0b7965 100644
--- a/maxscale-system-test/maxtest/src/tcp_connection.cpp
+++ b/maxscale-system-test/maxtest/src/tcp_connection.cc
@@ -1,4 +1,4 @@
-#include "tcp_connection.h"
+#include "tcp_connection.hh"
 
 #include <sys/types.h>
 #include <sys/socket.h>
diff --git a/maxscale-system-test/maxtest/src/test_binlog_fnc.cpp b/maxscale-system-test/maxtest/src/test_binlog_fnc.cc
similarity index 100%
rename from maxscale-system-test/maxtest/src/test_binlog_fnc.cpp
rename to maxscale-system-test/maxtest/src/test_binlog_fnc.cc
diff --git a/maxscale-system-test/maxtest/src/testconnections.cpp b/maxscale-system-test/maxtest/src/testconnections.cc
similarity index 99%
rename from maxscale-system-test/maxtest/src/testconnections.cpp
rename to maxscale-system-test/maxtest/src/testconnections.cc
index bc2a3bce4..7627680b7 100644
--- a/maxscale-system-test/maxtest/src/testconnections.cpp
+++ b/maxscale-system-test/maxtest/src/testconnections.cc
@@ -22,7 +22,7 @@
 #include "sql_t1.h"
 #include "testconnections.h"
 #include "test_info.hh"
-#include "envv.h"
+#include "envv.hh"
 
 using namespace mxb;
 using std::cout;
diff --git a/maxscale-system-test/mxs1628_bad_handshake.cpp b/maxscale-system-test/mxs1628_bad_handshake.cpp
index 39f0cbddd..d374d4058 100644
--- a/maxscale-system-test/mxs1628_bad_handshake.cpp
+++ b/maxscale-system-test/mxs1628_bad_handshake.cpp
@@ -1,5 +1,5 @@
 #include "testconnections.h"
-#include "tcp_connection.h"
+#include "tcp_connection.hh"
 
 #include <vector>
 
diff --git a/maxscale-system-test/mxs173_throttle_filter.cpp b/maxscale-system-test/mxs173_throttle_filter.cpp
index fbc7c36d6..6eaba8628 100644
--- a/maxscale-system-test/mxs173_throttle_filter.cpp
+++ b/maxscale-system-test/mxs173_throttle_filter.cpp
@@ -4,8 +4,8 @@
  */
 
 #include "testconnections.h"
-#include "stopwatch.h"
-#include "appexception.h"
+#include "stopwatch.hh"
+#include "appexception.hh"
 #include <iostream>
 #include <memory>
 #include <sstream>