diff --git a/include/EntityManager.hpp b/include/entity_manager.hpp
similarity index 98%
rename from include/EntityManager.hpp
rename to include/entity_manager.hpp
index 2d79e1f..a851866 100644
--- a/include/EntityManager.hpp
+++ b/include/entity_manager.hpp
@@ -13,11 +13,11 @@
 // See the License for the specific language governing permissions and
 // limitations under the License.
 */
-/// \file EntityManager.hpp
+/// \file entity_manager.hpp
 
 #pragma once
 
-#include "Utils.hpp"
+#include "utils.hpp"
 
 #include <systemd/sd-journal.h>
 
diff --git a/include/Expression.hpp b/include/expression.hpp
similarity index 100%
rename from include/Expression.hpp
rename to include/expression.hpp
diff --git a/include/FruUtils.hpp b/include/fru_utils.hpp
similarity index 99%
rename from include/FruUtils.hpp
rename to include/fru_utils.hpp
index 8d94876..c072ae5 100644
--- a/include/FruUtils.hpp
+++ b/include/fru_utils.hpp
@@ -13,7 +13,7 @@
 // See the License for the specific language governing permissions and
 // limitations under the License.
 */
-/// \file FruUtils.hpp
+/// \file fru_utils.hpp
 
 #pragma once
 #include <boost/container/flat_map.hpp>
diff --git a/include/Overlay.hpp b/include/overlay.hpp
similarity index 97%
rename from include/Overlay.hpp
rename to include/overlay.hpp
index 0b38da4..e11f1b8 100644
--- a/include/Overlay.hpp
+++ b/include/overlay.hpp
@@ -13,7 +13,7 @@
 // See the License for the specific language governing permissions and
 // limitations under the License.
 */
-/// \file Overlay.hpp
+/// \file overlay.hpp
 
 #pragma once
 #include <nlohmann/json.hpp>
diff --git a/include/Utils.hpp b/include/utils.hpp
similarity index 99%
rename from include/Utils.hpp
rename to include/utils.hpp
index c54559a..bc8ac1b 100644
--- a/include/Utils.hpp
+++ b/include/utils.hpp
@@ -13,7 +13,7 @@
 // See the License for the specific language governing permissions and
 // limitations under the License.
 */
-/// \file Utils.hpp
+/// \file utils.hpp
 
 #pragma once
 
diff --git a/include/VariantVisitors.hpp b/include/variant_visitors.hpp
similarity index 97%
rename from include/VariantVisitors.hpp
rename to include/variant_visitors.hpp
index 771d7d1..87ae750 100644
--- a/include/VariantVisitors.hpp
+++ b/include/variant_visitors.hpp
@@ -13,7 +13,7 @@
 // See the License for the specific language governing permissions and
 // limitations under the License.
 */
-/// \file VariantVisitors.hpp
+/// \file variant_visitors.hpp
 
 #pragma once
 #include <stdexcept>
diff --git a/meson.build b/meson.build
index 5264985..aeb6445 100644
--- a/meson.build
+++ b/meson.build
@@ -203,8 +203,8 @@
         executable(
             'test_entity_manager',
             'test/test_entity-manager.cpp',
-            'src/Expression.cpp',
-            'src/Utils.cpp',
+            'src/expression.cpp',
+            'src/utils.cpp',
             cpp_args: test_boost_args,
             dependencies: [
                 boost,
@@ -223,7 +223,7 @@
         executable(
             'test_fru_utils',
             'test/test_fru-utils.cpp',
-            'src/FruUtils.cpp',
+            'src/fru_utils.cpp',
             cpp_args: test_boost_args,
             dependencies: [
                 boost,
diff --git a/src/EntityManager.cpp b/src/entity_manager.cpp
similarity index 99%
rename from src/EntityManager.cpp
rename to src/entity_manager.cpp
index 8f29f92..641d3f9 100644
--- a/src/EntityManager.cpp
+++ b/src/entity_manager.cpp
@@ -13,13 +13,13 @@
 // See the License for the specific language governing permissions and
 // limitations under the License.
 */
-/// \file EntityManager.cpp
+/// \file entity_manager.cpp
 
-#include "EntityManager.hpp"
+#include "entity_manager.hpp"
 
-#include "Overlay.hpp"
-#include "Utils.hpp"
-#include "VariantVisitors.hpp"
+#include "overlay.hpp"
+#include "utils.hpp"
+#include "variant_visitors.hpp"
 
 #include <boost/algorithm/string/case_conv.hpp>
 #include <boost/algorithm/string/classification.hpp>
diff --git a/src/Expression.cpp b/src/expression.cpp
similarity index 98%
rename from src/Expression.cpp
rename to src/expression.cpp
index 34be337..50fcbe3 100644
--- a/src/Expression.cpp
+++ b/src/expression.cpp
@@ -15,7 +15,7 @@
 // limitations under the License.
 */
 
-#include "Expression.hpp"
+#include "expression.hpp"
 
 #include <iostream>
 #include <stdexcept>
diff --git a/src/FruDevice.cpp b/src/fru_device.cpp
similarity index 99%
rename from src/FruDevice.cpp
rename to src/fru_device.cpp
index 86644fd..af53e7f 100644
--- a/src/FruDevice.cpp
+++ b/src/fru_device.cpp
@@ -13,10 +13,10 @@
 // See the License for the specific language governing permissions and
 // limitations under the License.
 */
-/// \file FruDevice.cpp
+/// \file fru_device.cpp
 
-#include "FruUtils.hpp"
-#include "Utils.hpp"
+#include "fru_utils.hpp"
+#include "utils.hpp"
 
 #include <fcntl.h>
 #include <sys/inotify.h>
diff --git a/src/FruUtils.cpp b/src/fru_utils.cpp
similarity index 99%
rename from src/FruUtils.cpp
rename to src/fru_utils.cpp
index 70f461c..62390c6 100644
--- a/src/FruUtils.cpp
+++ b/src/fru_utils.cpp
@@ -13,9 +13,9 @@
 // See the License for the specific language governing permissions and
 // limitations under the License.
 */
-/// \file FruUtils.cpp
+/// \file fru_utils.cpp
 
-#include "FruUtils.hpp"
+#include "fru_utils.hpp"
 
 #include <array>
 #include <cstdint>
diff --git a/src/meson.build b/src/meson.build
index 411f0d4..8ddb21e 100644
--- a/src/meson.build
+++ b/src/meson.build
@@ -3,12 +3,12 @@
 
 executable(
     'entity-manager',
-    'EntityManager.cpp',
-    'Expression.cpp',
-    'PerformScan.cpp',
-    'PerformProbe.cpp',
-    'Overlay.cpp',
-    'Utils.cpp',
+    'entity_manager.cpp',
+    'expression.cpp',
+    'perform_scan.cpp',
+    'perform_probe.cpp',
+    'overlay.cpp',
+    'utils.cpp',
     cpp_args: cpp_args + ['-DBOOST_ASIO_DISABLE_THREADS'],
     dependencies: [
         boost,
@@ -28,10 +28,10 @@
     endif
     executable(
         'fru-device',
-        'Expression.cpp',
-        'FruDevice.cpp',
-        'Utils.cpp',
-        'FruUtils.cpp',
+        'expression.cpp',
+        'fru_device.cpp',
+        'utils.cpp',
+        'fru_utils.cpp',
         cpp_args: cpp_args_fd,
         dependencies: [
             boost,
diff --git a/src/Overlay.cpp b/src/overlay.cpp
similarity index 99%
rename from src/Overlay.cpp
rename to src/overlay.cpp
index 4454423..1d99a79 100644
--- a/src/Overlay.cpp
+++ b/src/overlay.cpp
@@ -13,11 +13,11 @@
 // See the License for the specific language governing permissions and
 // limitations under the License.
 */
-/// \file Overlay.cpp
+/// \file overlay.cpp
 
-#include "Overlay.hpp"
+#include "overlay.hpp"
 
-#include "Utils.hpp"
+#include "utils.hpp"
 #include "devices.hpp"
 
 #include <boost/algorithm/string/predicate.hpp>
diff --git a/src/PerformProbe.cpp b/src/perform_probe.cpp
similarity index 98%
rename from src/PerformProbe.cpp
rename to src/perform_probe.cpp
index af9373c..d5b7f3b 100644
--- a/src/PerformProbe.cpp
+++ b/src/perform_probe.cpp
@@ -13,8 +13,8 @@
 // See the License for the specific language governing permissions and
 // limitations under the License.
 */
-/// \file PerformProbe.cpp
-#include "EntityManager.hpp"
+/// \file perform_probe.cpp
+#include "entity_manager.hpp"
 
 #include <boost/algorithm/string/replace.hpp>
 
diff --git a/src/PerformScan.cpp b/src/perform_scan.cpp
similarity index 99%
rename from src/PerformScan.cpp
rename to src/perform_scan.cpp
index 144b824..959a819 100644
--- a/src/PerformScan.cpp
+++ b/src/perform_scan.cpp
@@ -13,8 +13,8 @@
 // See the License for the specific language governing permissions and
 // limitations under the License.
 */
-/// \file PerformScan.cpp
-#include "EntityManager.hpp"
+/// \file perform_scan.cpp
+#include "entity_manager.hpp"
 
 #include <boost/algorithm/string/predicate.hpp>
 #include <boost/asio/steady_timer.hpp>
@@ -23,7 +23,7 @@
 
 #include <charconv>
 
-/* Hacks from splitting EntityManager.cpp */
+/* Hacks from splitting entity_manager.cpp */
 extern std::shared_ptr<sdbusplus::asio::connection> systemBus;
 extern nlohmann::json lastJson;
 extern void
diff --git a/src/Utils.cpp b/src/utils.cpp
similarity index 99%
rename from src/Utils.cpp
rename to src/utils.cpp
index 612e495..8b7386d 100644
--- a/src/Utils.cpp
+++ b/src/utils.cpp
@@ -13,12 +13,12 @@
 // See the License for the specific language governing permissions and
 // limitations under the License.
 */
-/// \file Utils.cpp
+/// \file utils.cpp
 
-#include "Utils.hpp"
+#include "utils.hpp"
 
-#include "Expression.hpp"
-#include "VariantVisitors.hpp"
+#include "expression.hpp"
+#include "variant_visitors.hpp"
 
 #include <boost/algorithm/string/classification.hpp>
 #include <boost/algorithm/string/find.hpp>
diff --git a/test/test_entity-manager.cpp b/test/test_entity-manager.cpp
index b1eec84..4cd841a 100644
--- a/test/test_entity-manager.cpp
+++ b/test/test_entity-manager.cpp
@@ -1,4 +1,4 @@
-#include "Utils.hpp"
+#include "utils.hpp"
 
 #include <nlohmann/json.hpp>
 
diff --git a/test/test_fru-utils.cpp b/test/test_fru-utils.cpp
index 60b71e0..5a6ce52 100644
--- a/test/test_fru-utils.cpp
+++ b/test/test_fru-utils.cpp
@@ -1,4 +1,4 @@
-#include "FruUtils.hpp"
+#include "fru_utils.hpp"
 
 #include <algorithm>
 #include <array>