diff --git a/CHANGELOG.md b/CHANGELOG.md
index 9af0709..ae0f49d 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -1,5 +1,9 @@
 # Changelog
 
+## Development Build: v2.5.0-rc4_dev81
+- define msgids via topicids
+- See <https://github.com/nasa/ci_lab/pull/165>
+
 ## Development Build: v2.5.0-rc4+dev77
 - Remove unused PDU related function codes
 - Remove obsolete README comment
diff --git a/arch_build.cmake b/arch_build.cmake
index ac79159..200aee6 100644
--- a/arch_build.cmake
+++ b/arch_build.cmake
@@ -20,8 +20,14 @@ set(CI_LAB_PLATFORM_CONFIG_FILE_LIST
 # This makes them individually overridable by the missions, without modifying
 # the distribution default copies
 foreach(CI_LAB_CFGFILE ${CI_LAB_PLATFORM_CONFIG_FILE_LIST})
+  get_filename_component(CFGKEY "${CI_LAB_CFGFILE}" NAME_WE)
+  if (DEFINED CI_LAB_CFGFILE_SRC_${CFGKEY})
+    set(DEFAULT_SOURCE GENERATED_FILE "${CI_LAB_CFGFILE_SRC_${CFGKEY}}")
+  else()
+    set(DEFAULT_SOURCE FALLBACK_FILE "${CMAKE_CURRENT_LIST_DIR}/config/default_${CI_LAB_CFGFILE}")
+  endif()
   generate_config_includefile(
     FILE_NAME           "${CI_LAB_CFGFILE}"
-    FALLBACK_FILE       "${CMAKE_CURRENT_LIST_DIR}/config/default_${CI_LAB_CFGFILE}"
+    ${DEFAULT_SOURCE}
   )
 endforeach()
diff --git a/config/default_ci_lab_msgids.h b/config/default_ci_lab_msgids.h
index feefb97..18f841a 100644
--- a/config/default_ci_lab_msgids.h
+++ b/config/default_ci_lab_msgids.h
@@ -23,9 +23,11 @@
 #ifndef CI_LAB_MSGIDS_H
 #define CI_LAB_MSGIDS_H
 
-#define CI_LAB_CMD_MID     0x1884
-#define CI_LAB_SEND_HK_MID 0x1885
+#include "cfe_core_api_base_msgids.h"
+#include "ci_lab_topicids.h"
 
-#define CI_LAB_HK_TLM_MID 0x0884
+#define CI_LAB_CMD_MID     CFE_PLATFORM_CMD_TOPICID_TO_MIDV(CI_LAB_CMD_TOPICID)
+#define CI_LAB_SEND_HK_MID CFE_PLATFORM_CMD_TOPICID_TO_MIDV(CI_LAB_SEND_HK_TOPICID)
+#define CI_LAB_HK_TLM_MID  CFE_PLATFORM_TLM_TOPICID_TO_MIDV(CI_LAB_HK_TLM_TOPICID)
 
 #endif
diff --git a/config/default_ci_lab_topicids.h b/config/default_ci_lab_topicids.h
new file mode 100644
index 0000000..24f2ad5
--- /dev/null
+++ b/config/default_ci_lab_topicids.h
@@ -0,0 +1,30 @@
+/************************************************************************
+ * NASA Docket No. GSC-18,719-1, and identified as “core Flight System: Bootes”
+ *
+ * Copyright (c) 2020 United States Government as represented by the
+ * Administrator of the National Aeronautics and Space Administration.
+ * All Rights Reserved.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License"); you may
+ * not use this file except in compliance with the License. You may obtain
+ * a copy of the License at http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ ************************************************************************/
+
+/**
+ * @file
+ *   CI_LAB Application Topic IDs
+ */
+#ifndef CI_LAB_TOPICIDS_H
+#define CI_LAB_TOPICIDS_H
+
+#define CI_LAB_CMD_TOPICID     0x84
+#define CI_LAB_SEND_HK_TOPICID 0x85
+#define CI_LAB_HK_TLM_TOPICID  0x84
+
+#endif
diff --git a/fsw/src/ci_lab_version.h b/fsw/src/ci_lab_version.h
index 2a03aef..234e7d9 100644
--- a/fsw/src/ci_lab_version.h
+++ b/fsw/src/ci_lab_version.h
@@ -25,7 +25,7 @@
 
 /* Development Build Macro Definitions */
 
-#define CI_LAB_BUILD_NUMBER 77 /*!< Development Build: Number of commits since baseline */
+#define CI_LAB_BUILD_NUMBER 81 /*!< Development Build: Number of commits since baseline */
 #define CI_LAB_BUILD_BASELINE \
     "v2.5.0-rc4" /*!< Development Build: git tag that is the base for the current development */
 
diff --git a/mission_build.cmake b/mission_build.cmake
index c851706..01c0934 100644
--- a/mission_build.cmake
+++ b/mission_build.cmake
@@ -17,6 +17,7 @@ set(CI_LAB_MISSION_CONFIG_FILE_LIST
   ci_lab_msgdefs.h
   ci_lab_msg.h
   ci_lab_msgstruct.h
+  ci_lab_topicids.h
 )
 
 if (CFE_EDS_ENABLED_BUILD)