diff --git a/services/mediametrics/Android.bp b/services/mediametrics/Android.bp
index c87fbd9..645d151 100644
--- a/services/mediametrics/Android.bp
+++ b/services/mediametrics/Android.bp
@@ -1,8 +1,94 @@
 // Media Statistics service
 //
 
+tidy_errors = [
+    // https://clang.llvm.org/extra/clang-tidy/checks/list.html
+    // For many categories, the checks are too many to specify individually.
+    // Feel free to disable as needed - as warnings are generally ignored,
+    // we treat warnings as errors.
+    "android-*",
+    "bugprone-*",
+    "cert-*",
+    "clang-analyzer-security*",
+    "google-*",
+    "misc-*",
+    //"modernize-*",  // explicitly list the modernize as they can be subjective.
+    "modernize-avoid-bind",
+    //"modernize-avoid-c-arrays", // std::array<> can be verbose
+    "modernize-concat-nested-namespaces",
+    //"modernize-deprecated-headers", // C headers still ok even if there is C++ equivalent.
+    "modernize-deprecated-ios-base-aliases",
+    "modernize-loop-convert",
+    "modernize-make-shared",
+    "modernize-make-unique",
+    "modernize-pass-by-value",
+    "modernize-raw-string-literal",
+    "modernize-redundant-void-arg",
+    "modernize-replace-auto-ptr",
+    "modernize-replace-random-shuffle",
+    "modernize-return-braced-init-list",
+    "modernize-shrink-to-fit",
+    "modernize-unary-static-assert",
+    "modernize-use-auto",  // debatable - auto can obscure type
+    "modernize-use-bool-literals",
+    "modernize-use-default-member-init",
+    "modernize-use-emplace",
+    "modernize-use-equals-default",
+    "modernize-use-equals-delete",
+    "modernize-use-nodiscard",
+    "modernize-use-noexcept",
+    "modernize-use-nullptr",
+    "modernize-use-override",
+    //"modernize-use-trailing-return-type", // not necessarily more readable
+    "modernize-use-transparent-functors",
+    "modernize-use-uncaught-exceptions",
+    "modernize-use-using",
+    "performance-*",
+
+    // Remove some pedantic stylistic requirements.
+    "-google-readability-casting", // C++ casts not always necessary and may be verbose
+    "-google-readability-todo",    // do not require TODO(info)
+]
+
+cc_defaults {
+    name: "mediametrics_flags_defaults",
+    // https://clang.llvm.org/docs/UsersManual.html#command-line-options
+    // https://clang.llvm.org/docs/DiagnosticsReference.html
+    cflags: [
+        "-Wall",
+        "-Wdeprecated",
+        "-Werror",
+        "-Werror=implicit-fallthrough",
+        "-Werror=sometimes-uninitialized",
+        "-Werror=conditional-uninitialized",
+        "-Wextra",
+        "-Wredundant-decls",
+        "-Wshadow",
+        "-Wstrict-aliasing",
+        "-fstrict-aliasing",
+        "-Wthread-safety",
+        //"-Wthread-safety-negative", // experimental - looks broken in R.
+        "-Wunreachable-code",
+        "-Wunreachable-code-break",
+        "-Wunreachable-code-return",
+        "-Wunused",
+        "-Wused-but-marked-unused",
+    ],
+    // https://clang.llvm.org/extra/clang-tidy/
+    tidy: true,
+    tidy_checks: tidy_errors,
+    tidy_checks_as_errors: tidy_errors,
+    tidy_flags: [
+      "-format-style='file'",
+      "--header-filter='frameworks/av/services/mediametrics/'",
+    ],
+}
+
 cc_binary {
     name: "mediametrics",
+    defaults: [
+        "mediametrics_flags_defaults",
+    ],
 
     srcs: [
         "main_mediametrics.cpp",
@@ -22,17 +108,13 @@
     init_rc: [
         "mediametrics.rc",
     ],
-
-    cflags: [
-        "-Wall",
-        "-Werror",
-        "-Wextra",
-        "-Wthread-safety",
-    ],
 }
 
 cc_library_shared {
     name: "libmediametricsservice",
+    defaults: [
+        "mediametrics_flags_defaults",
+    ],
 
     srcs: [
         "AudioAnalytics.cpp",
@@ -73,11 +155,4 @@
     include_dirs: [
         "system/media/audio_utils/include",
     ],
-
-    cflags: [
-        "-Wall",
-        "-Werror",
-        "-Wextra",
-        "-Wthread-safety",
-    ],
 }
diff --git a/services/mediametrics/AudioAnalytics.cpp b/services/mediametrics/AudioAnalytics.cpp
index 6138d32..31ad234 100644
--- a/services/mediametrics/AudioAnalytics.cpp
+++ b/services/mediametrics/AudioAnalytics.cpp
@@ -594,4 +594,4 @@
 #endif
 }
 
-} // namespace android
+} // namespace android::mediametrics
diff --git a/services/mediametrics/AudioPowerUsage.cpp b/services/mediametrics/AudioPowerUsage.cpp
index b1615bd..b1648d9 100644
--- a/services/mediametrics/AudioPowerUsage.cpp
+++ b/services/mediametrics/AudioPowerUsage.cpp
@@ -160,7 +160,7 @@
         return true; //ignore unknown device
     }
 
-    for (auto item : mItems) {
+    for (const auto& item : mItems) {
         int32_t item_type = 0, item_device = 0;
         double item_volume = 0.;
         int64_t item_duration_ns = 0;
@@ -259,8 +259,8 @@
         const int64_t endCallNs = item->getTimestamp();
         const int64_t durationNs = endCallNs - mDeviceTimeNs;
         if (durationNs > 0) {
-            mDeviceVolume = (mDeviceVolume * (mVolumeTimeNs - mDeviceTimeNs) +
-                    mVoiceVolume * (endCallNs - mVolumeTimeNs)) / durationNs;
+            mDeviceVolume = (mDeviceVolume * double(mVolumeTimeNs - mDeviceTimeNs) +
+                    mVoiceVolume * double(endCallNs - mVolumeTimeNs)) / durationNs;
             saveAsItem_l(mPrimaryDevice, durationNs, VOICE_CALL_TYPE, mDeviceVolume);
         }
     } else if (mode == "AUDIO_MODE_IN_CALL") { // entering call mode
@@ -287,8 +287,8 @@
         const int64_t timeNs = item->getTimestamp();
         const int64_t durationNs = timeNs - mDeviceTimeNs;
         if (durationNs > 0) {
-            mDeviceVolume = (mDeviceVolume * (mVolumeTimeNs - mDeviceTimeNs) +
-                    mVoiceVolume * (timeNs - mVolumeTimeNs)) / durationNs;
+            mDeviceVolume = (mDeviceVolume * double(mVolumeTimeNs - mDeviceTimeNs) +
+                    mVoiceVolume * double(timeNs - mVolumeTimeNs)) / durationNs;
             mVolumeTimeNs = timeNs;
         }
     }
@@ -318,8 +318,8 @@
         const int64_t endDeviceNs = item->getTimestamp();
         const int64_t durationNs = endDeviceNs - mDeviceTimeNs;
         if (durationNs > 0) {
-            mDeviceVolume = (mDeviceVolume * (mVolumeTimeNs - mDeviceTimeNs) +
-                    mVoiceVolume * (endDeviceNs - mVolumeTimeNs)) / durationNs;
+            mDeviceVolume = (mDeviceVolume * double(mVolumeTimeNs - mDeviceTimeNs) +
+                    mVoiceVolume * double(endDeviceNs - mVolumeTimeNs)) / durationNs;
             saveAsItem_l(mPrimaryDevice, durationNs, VOICE_CALL_TYPE, mDeviceVolume);
         }
         // reset statistics
@@ -391,4 +391,4 @@
     return { ss.str(), slot };
 }
 
-} // namespace android
+} // namespace android::mediametrics
diff --git a/services/mediametrics/MediaMetricsService.cpp b/services/mediametrics/MediaMetricsService.cpp
index 3b3dc3e..584bd13 100644
--- a/services/mediametrics/MediaMetricsService.cpp
+++ b/services/mediametrics/MediaMetricsService.cpp
@@ -32,7 +32,8 @@
 
 namespace android {
 
-using namespace mediametrics;
+using mediametrics::Item;
+using mediametrics::startsWith;
 
 // individual records kept in memory: age or count
 // age: <= 28 hours (1 1/6 days)
@@ -63,7 +64,7 @@
 bool MediaMetricsService::useUidForPackage(
         const std::string& package, const std::string& installer)
 {
-    if (strchr(package.c_str(), '.') == NULL) {
+    if (strchr(package.c_str(), '.') == nullptr) {
         return false;  // not of form 'com.whatever...'; assume internal and ok
     } else if (strncmp(package.c_str(), "android.", 8) == 0) {
         return false;  // android.* packages are assumed fine
@@ -203,9 +204,9 @@
 
     // Overwrite package name and version if the caller was untrusted or empty
     if (!isTrusted || item->getPkgName().empty()) {
-        const uid_t uid = item->getUid();
+        const uid_t uidItem = item->getUid();
         const auto [ pkgName, version ] =
-                MediaMetricsService::getSanitizedPackageNameAndVersionCode(uid);
+                MediaMetricsService::getSanitizedPackageNameAndVersionCode(uidItem);
         item->setPkgName(pkgName);
         item->setPkgVersionCode(version);
     }
@@ -320,7 +321,7 @@
                 String8 value(args[i]);
                 char *endp;
                 const char *p = value.string();
-                long long sec = strtoll(p, &endp, 10);
+                const auto sec = (int64_t)strtoll(p, &endp, 10);
                 if (endp == p || *endp != '\0' || sec == 0) {
                     sinceNs = 0;
                 } else if (sec < 0) {
diff --git a/services/mediametrics/TimeMachine.h b/services/mediametrics/TimeMachine.h
index c82778b..00a44a4 100644
--- a/services/mediametrics/TimeMachine.h
+++ b/services/mediametrics/TimeMachine.h
@@ -18,6 +18,7 @@
 
 #include <any>
 #include <map>
+#include <mutex>
 #include <sstream>
 #include <string>
 #include <variant>
@@ -81,6 +82,8 @@
             , mCreationTime(time)
             , mLastModificationTime(time)
         {
+            (void)mCreationTime; // suppress unused warning.
+
             // allowUid allows an untrusted client with a matching uid to set properties
             // in this key.
             // If allowUid == (uid_t)-1, no untrusted client may set properties in the key.
@@ -209,7 +212,7 @@
 
         const std::string mKey;
         const uid_t mAllowUid;
-        const int64_t mCreationTime __unused;
+        const int64_t mCreationTime;
 
         int64_t mLastModificationTime;
         std::map<std::string /* property */, PropertyHistory> mPropertyMap;
@@ -442,7 +445,7 @@
                 ++it) {
             if (ll <= 0) break;
             if (prefix != nullptr && !startsWith(it->first, prefix)) break;
-            std::lock_guard lock(getLockForKey(it->first));
+            std::lock_guard lock2(getLockForKey(it->first));
             auto [s, l] = it->second->dump(ll, sinceNs);
             ss << s;
             ll -= l;
diff --git a/services/mediametrics/iface_statsd.cpp b/services/mediametrics/iface_statsd.cpp
index 3a1eea7..6e51f72 100644
--- a/services/mediametrics/iface_statsd.cpp
+++ b/services/mediametrics/iface_statsd.cpp
@@ -71,7 +71,7 @@
 
 // give me a record, i'll look at the type and upload appropriately
 bool dump2Statsd(const std::shared_ptr<const mediametrics::Item>& item) {
-    if (item == NULL) return false;
+    if (item == nullptr) return false;
 
     // get the key
     std::string key = item->getKey();
diff --git a/services/mediametrics/main_mediametrics.cpp b/services/mediametrics/main_mediametrics.cpp
index 6992c32..3a66538 100644
--- a/services/mediametrics/main_mediametrics.cpp
+++ b/services/mediametrics/main_mediametrics.cpp
@@ -25,9 +25,9 @@
 #include <binder/ProcessState.h>
 #include <mediautils/LimitProcessMemory.h>
 
-int main(int argc __unused, char **argv __unused)
+int main(int argc __unused, char **argv)
 {
-    using namespace android;
+    using namespace android; // NOLINT (clang-tidy)
 
     limitProcessMemory(
         "media.metrics.maxmem", /* property that defines limit */
@@ -39,7 +39,8 @@
     // to match the service name
     // we're replacing "/system/bin/mediametrics" with "media.metrics"
     // we add a ".", but discard the path components: we finish with a shorter string
-    strcpy(argv[0], MediaMetricsService::kServiceName);
+    const size_t origSize = strlen(argv[0]) + 1; // include null termination.
+    strlcpy(argv[0], MediaMetricsService::kServiceName, origSize);
 
     defaultServiceManager()->addService(
             String16(MediaMetricsService::kServiceName), new MediaMetricsService());
diff --git a/services/mediametrics/statsd_audiopolicy.cpp b/services/mediametrics/statsd_audiopolicy.cpp
index 634c801..393c6ae 100644
--- a/services/mediametrics/statsd_audiopolicy.cpp
+++ b/services/mediametrics/statsd_audiopolicy.cpp
@@ -39,7 +39,7 @@
 
 bool statsd_audiopolicy(const mediametrics::Item *item)
 {
-    if (item == NULL) return false;
+    if (item == nullptr) return false;
 
     // these go into the statsd wrapper
     const nsecs_t timestamp = MediaMetricsService::roundTime(item->getTimestamp());
@@ -122,4 +122,4 @@
     return true;
 }
 
-};
+} // namespace android
diff --git a/services/mediametrics/statsd_audiorecord.cpp b/services/mediametrics/statsd_audiorecord.cpp
index 69d1661..43feda1 100644
--- a/services/mediametrics/statsd_audiorecord.cpp
+++ b/services/mediametrics/statsd_audiorecord.cpp
@@ -39,7 +39,7 @@
 
 bool statsd_audiorecord(const mediametrics::Item *item)
 {
-    if (item == NULL) return false;
+    if (item == nullptr) return false;
 
     // these go into the statsd wrapper
     const nsecs_t timestamp = MediaMetricsService::roundTime(item->getTimestamp());
@@ -155,4 +155,4 @@
     return true;
 }
 
-};
+} // namespace android
diff --git a/services/mediametrics/statsd_audiothread.cpp b/services/mediametrics/statsd_audiothread.cpp
index 300151b..e867f5b 100644
--- a/services/mediametrics/statsd_audiothread.cpp
+++ b/services/mediametrics/statsd_audiothread.cpp
@@ -39,7 +39,7 @@
 
 bool statsd_audiothread(const mediametrics::Item *item)
 {
-    if (item == NULL) return false;
+    if (item == nullptr) return false;
 
     // these go into the statsd wrapper
     const nsecs_t timestamp = MediaMetricsService::roundTime(item->getTimestamp());
@@ -204,4 +204,4 @@
     return true;
 }
 
-};
+} // namespace android
diff --git a/services/mediametrics/statsd_audiotrack.cpp b/services/mediametrics/statsd_audiotrack.cpp
index 397cdf3..ee5b9b2 100644
--- a/services/mediametrics/statsd_audiotrack.cpp
+++ b/services/mediametrics/statsd_audiotrack.cpp
@@ -39,7 +39,7 @@
 
 bool statsd_audiotrack(const mediametrics::Item *item)
 {
-    if (item == NULL) return false;
+    if (item == nullptr) return false;
 
     // these go into the statsd wrapper
     const nsecs_t timestamp = MediaMetricsService::roundTime(item->getTimestamp());
@@ -146,4 +146,4 @@
     return true;
 }
 
-};
+} // namespace android
diff --git a/services/mediametrics/statsd_codec.cpp b/services/mediametrics/statsd_codec.cpp
index f5fa57e..7a38c7c 100644
--- a/services/mediametrics/statsd_codec.cpp
+++ b/services/mediametrics/statsd_codec.cpp
@@ -39,7 +39,7 @@
 
 bool statsd_codec(const mediametrics::Item *item)
 {
-    if (item == NULL) return false;
+    if (item == nullptr) return false;
 
     // these go into the statsd wrapper
     const nsecs_t timestamp = MediaMetricsService::roundTime(item->getTimestamp());
@@ -188,4 +188,4 @@
     return true;
 }
 
-};
+} // namespace android
diff --git a/services/mediametrics/statsd_drm.cpp b/services/mediametrics/statsd_drm.cpp
index 4f2e861..89d6f8f 100644
--- a/services/mediametrics/statsd_drm.cpp
+++ b/services/mediametrics/statsd_drm.cpp
@@ -43,22 +43,22 @@
 // mediadrm
 bool statsd_mediadrm(const mediametrics::Item *item)
 {
-    if (item == NULL) return false;
+    if (item == nullptr) return false;
 
     const nsecs_t timestamp = MediaMetricsService::roundTime(item->getTimestamp());
     std::string pkgName = item->getPkgName();
     int64_t pkgVersionCode = item->getPkgVersionCode();
     int64_t mediaApexVersion = 0;
 
-    char *vendor = NULL;
+    char *vendor = nullptr;
     (void) item->getCString("vendor", &vendor);
-    char *description = NULL;
+    char *description = nullptr;
     (void) item->getCString("description", &description);
-    char *serialized_metrics = NULL;
+    char *serialized_metrics = nullptr;
     (void) item->getCString("serialized_metrics", &serialized_metrics);
 
     if (enabled_statsd) {
-        android::util::BytesField bf_serialized(serialized_metrics ? serialized_metrics : NULL,
+        android::util::BytesField bf_serialized(serialized_metrics ? serialized_metrics : nullptr,
                                                 serialized_metrics ? strlen(serialized_metrics)
                                                                    : 0);
         android::util::stats_write(android::util::MEDIAMETRICS_MEDIADRM_REPORTED,
@@ -80,18 +80,18 @@
 // widevineCDM
 bool statsd_widevineCDM(const mediametrics::Item *item)
 {
-    if (item == NULL) return false;
+    if (item == nullptr) return false;
 
     const nsecs_t timestamp = MediaMetricsService::roundTime(item->getTimestamp());
     std::string pkgName = item->getPkgName();
     int64_t pkgVersionCode = item->getPkgVersionCode();
     int64_t mediaApexVersion = 0;
 
-    char *serialized_metrics = NULL;
+    char *serialized_metrics = nullptr;
     (void) item->getCString("serialized_metrics", &serialized_metrics);
 
     if (enabled_statsd) {
-        android::util::BytesField bf_serialized(serialized_metrics ? serialized_metrics : NULL,
+        android::util::BytesField bf_serialized(serialized_metrics ? serialized_metrics : nullptr,
                                                 serialized_metrics ? strlen(serialized_metrics)
                                                                    : 0);
         android::util::stats_write(android::util::MEDIAMETRICS_DRM_WIDEVINE_REPORTED,
@@ -111,7 +111,7 @@
 bool statsd_drmmanager(const mediametrics::Item *item)
 {
     using namespace std::string_literals;
-    if (item == NULL) return false;
+    if (item == nullptr) return false;
 
     if (!enabled_statsd) {
         ALOGV("NOT sending: drmmanager data");
@@ -123,13 +123,13 @@
     int64_t pkgVersionCode = item->getPkgVersionCode();
     int64_t mediaApexVersion = 0;
 
-    char *plugin_id = NULL;
+    char *plugin_id = nullptr;
     (void) item->getCString("plugin_id", &plugin_id);
-    char *description = NULL;
+    char *description = nullptr;
     (void) item->getCString("description", &description);
     int32_t method_id = -1;
     (void) item->getInt32("method_id", &method_id);
-    char *mime_types = NULL;
+    char *mime_types = nullptr;
     (void) item->getCString("mime_types", &mime_types);
 
     // Corresponds to the 13 APIs tracked in the MediametricsDrmManagerReported statsd proto
diff --git a/services/mediametrics/statsd_extractor.cpp b/services/mediametrics/statsd_extractor.cpp
index 8574358..3d5739f 100644
--- a/services/mediametrics/statsd_extractor.cpp
+++ b/services/mediametrics/statsd_extractor.cpp
@@ -39,7 +39,7 @@
 
 bool statsd_extractor(const mediametrics::Item *item)
 {
-    if (item == NULL) return false;
+    if (item == nullptr) return false;
 
     // these go into the statsd wrapper
     const nsecs_t timestamp = MediaMetricsService::roundTime(item->getTimestamp());
@@ -91,4 +91,4 @@
     return true;
 }
 
-};
+} // namespace android
diff --git a/services/mediametrics/statsd_nuplayer.cpp b/services/mediametrics/statsd_nuplayer.cpp
index df7e59f..488bdcb 100644
--- a/services/mediametrics/statsd_nuplayer.cpp
+++ b/services/mediametrics/statsd_nuplayer.cpp
@@ -43,7 +43,7 @@
  */
 bool statsd_nuplayer(const mediametrics::Item *item)
 {
-    if (item == NULL) return false;
+    if (item == nullptr) return false;
 
     // these go into the statsd wrapper
     const nsecs_t timestamp = MediaMetricsService::roundTime(item->getTimestamp());
@@ -167,4 +167,4 @@
     return true;
 }
 
-};
+} // namespace android
diff --git a/services/mediametrics/statsd_recorder.cpp b/services/mediametrics/statsd_recorder.cpp
index 4de1746..6d5fca0 100644
--- a/services/mediametrics/statsd_recorder.cpp
+++ b/services/mediametrics/statsd_recorder.cpp
@@ -39,7 +39,7 @@
 
 bool statsd_recorder(const mediametrics::Item *item)
 {
-    if (item == NULL) return false;
+    if (item == nullptr) return false;
 
     // these go into the statsd wrapper
     const nsecs_t timestamp = MediaMetricsService::roundTime(item->getTimestamp());
@@ -186,4 +186,4 @@
     return true;
 }
 
-};
+} // namespace android