diff --git a/lib/api/capi.cpp b/lib/api/capi.cpp
index 916c4ebda..cfe6e0a0e 100644
--- a/lib/api/capi.cpp
+++ b/lib/api/capi.cpp
@@ -49,7 +49,7 @@ capi_client * MAT::capi_get_client(evt_handle_t handle)
 /// <summary>
 /// Remove C API handle from active client tracking struct.
 /// </summary>
-void remove_client(evt_handle_t handle)
+static void remove_client(evt_handle_t handle)
 {
     LOCKGUARD(mtx);
     clients.erase(handle);
@@ -66,7 +66,7 @@ void remove_client(evt_handle_t handle)
         return ENOENT;                                          \
     };
 
-evt_status_t mat_open_core(
+static evt_status_t mat_open_core(
     evt_context_t *ctx,
     const char* config,
     http_send_fn_t httpSendFn,
@@ -175,7 +175,7 @@ evt_status_t mat_open_core(
     return ctx->result;
 }
 
-evt_status_t mat_open(evt_context_t *ctx)
+static evt_status_t mat_open(evt_context_t *ctx)
 {
     if (ctx == nullptr)
     {
@@ -186,7 +186,7 @@ evt_status_t mat_open(evt_context_t *ctx)
     return mat_open_core(ctx, config, nullptr, nullptr, nullptr, nullptr, nullptr);
 }
 
-evt_status_t mat_open_with_params(evt_context_t *ctx)
+static evt_status_t mat_open_with_params(evt_context_t *ctx)
 {
     if (ctx == nullptr)
     {
@@ -231,9 +231,9 @@ evt_status_t mat_open_with_params(evt_context_t *ctx)
 }
 
 /**
- * Marashal C struct to C++ API
+ * Marshal C struct to C++ API
  */
-evt_status_t mat_log(evt_context_t *ctx)
+static evt_status_t mat_log(evt_context_t *ctx)
 {
     VERIFY_CLIENT_HANDLE(client, ctx);
 
@@ -285,7 +285,7 @@ evt_status_t mat_log(evt_context_t *ctx)
     return ctx->result;
 }
 
-evt_status_t mat_close(evt_context_t *ctx)
+static evt_status_t mat_close(evt_context_t *ctx)
 {
     VERIFY_CLIENT_HANDLE(client, ctx);
     const auto result = static_cast<evt_status_t>(LogManagerProvider::Release(client->logmanager->GetLogConfiguration()));
@@ -305,7 +305,7 @@ evt_status_t mat_close(evt_context_t *ctx)
     return result;
 }
 
-evt_status_t mat_pause(evt_context_t *ctx)
+static evt_status_t mat_pause(evt_context_t *ctx)
 {
     VERIFY_CLIENT_HANDLE(client, ctx);
     const auto result = static_cast<evt_status_t>(client->logmanager->PauseTransmission());
@@ -313,7 +313,7 @@ evt_status_t mat_pause(evt_context_t *ctx)
     return result;
 }
 
-evt_status_t mat_resume(evt_context_t *ctx)
+static evt_status_t mat_resume(evt_context_t *ctx)
 {
     VERIFY_CLIENT_HANDLE(client, ctx);
     const auto result = static_cast<evt_status_t>(client->logmanager->ResumeTransmission());
@@ -321,7 +321,7 @@ evt_status_t mat_resume(evt_context_t *ctx)
     return result;
 }
 
-evt_status_t mat_upload(evt_context_t *ctx)
+static evt_status_t mat_upload(evt_context_t *ctx)
 {
     VERIFY_CLIENT_HANDLE(client, ctx);
     const auto result = static_cast<evt_status_t>(client->logmanager->UploadNow());
@@ -329,7 +329,7 @@ evt_status_t mat_upload(evt_context_t *ctx)
     return result;
 }
 
-evt_status_t mat_flushAndTeardown(evt_context_t *ctx)
+static evt_status_t mat_flushAndTeardown(evt_context_t *ctx)
 {
     VERIFY_CLIENT_HANDLE(client, ctx);
     client->logmanager->FlushAndTeardown();
diff --git a/lib/offline/MemoryStorage.hpp b/lib/offline/MemoryStorage.hpp
index 8a378dc5d..32dc82bdf 100644
--- a/lib/offline/MemoryStorage.hpp
+++ b/lib/offline/MemoryStorage.hpp
@@ -24,7 +24,7 @@
 
 namespace MAT_NS_BEGIN {
 
-    class MemoryStorage : public IOfflineStorage
+    class MemoryStorage final : public IOfflineStorage
     {
 
     public:
@@ -69,7 +69,7 @@ namespace MAT_NS_BEGIN {
 
         virtual size_t GetRemainingRecordCountForShutdown() const override;
 
-        virtual size_t GetReservedCount();
+        size_t GetReservedCount();
 
         virtual std::vector<StorageRecord> GetRecords(bool shutdown = false, EventLatency minLatency = EventLatency_Unspecified, unsigned maxCount = 0) override;
 
diff --git a/lib/offline/OfflineStorageHandler.hpp b/lib/offline/OfflineStorageHandler.hpp
index e7bdce4cb..1b07d5d1d 100644
--- a/lib/offline/OfflineStorageHandler.hpp
+++ b/lib/offline/OfflineStorageHandler.hpp
@@ -23,7 +23,7 @@
 
 namespace MAT_NS_BEGIN {
 
-    class OfflineStorageHandler : public IOfflineStorage, public IOfflineStorageObserver
+    class OfflineStorageHandler final : public IOfflineStorage, public IOfflineStorageObserver
     {
     public:
         OfflineStorageHandler(ILogManager& logManager, IRuntimeConfig& runtimeConfig, ITaskDispatcher& taskDispatcher);
@@ -64,7 +64,7 @@ namespace MAT_NS_BEGIN {
         virtual void OnStorageRecordsSaved(size_t numRecords) override;
 
     protected:
-        virtual void DeleteRecordsByKeys(const std::list<std::string> & keys);
+        void DeleteRecordsByKeys(const std::list<std::string> & keys);
 
         IOfflineStorageObserver   * m_observer;
         ILogManager &               m_logManager;
@@ -75,7 +75,7 @@ namespace MAT_NS_BEGIN {
         KillSwitchManager           m_killSwitchManager;
         ClockSkewManager            m_clockSkewManager;
 
-        virtual bool isKilled(StorageRecord const& record);
+        bool isKilled(StorageRecord const& record);
 
         std::mutex                             m_flushLock;
         bool                                   m_flushPending;
diff --git a/lib/shared/dllmain.cpp b/lib/shared/dllmain.cpp
index 4cfa868c6..d584c56c6 100644
--- a/lib/shared/dllmain.cpp
+++ b/lib/shared/dllmain.cpp
@@ -18,7 +18,7 @@
 #ifdef _MANAGED
 #pragma unmanaged
 #endif
-unsigned thread_count = 0;
+static unsigned thread_count = 0;
 
 BOOL APIENTRY DllMain(HMODULE /* hModule */, DWORD ul_reason_for_call, LPVOID /* lpReserved */)
 {