diff --git a/src/currency_core/bc_attachments_service_manager.h b/src/currency_core/bc_attachments_service_manager.h
index 8f95d699..bd4f2640 100644
--- a/src/currency_core/bc_attachments_service_manager.h
+++ b/src/currency_core/bc_attachments_service_manager.h
@@ -12,6 +12,8 @@ namespace currency
 {
   struct i_bc_service
   {
+    virtual ~i_bc_service() = default;
+
     virtual std::string get_id() = 0;
     virtual bool init(const std::string& config_folder, const boost::program_options::variables_map& vm) = 0;
     virtual bool deinit() = 0;
diff --git a/src/simplewallet/simplewallet.h b/src/simplewallet/simplewallet.h
index 2b138841..70fa3f85 100644
--- a/src/simplewallet/simplewallet.h
+++ b/src/simplewallet/simplewallet.h
@@ -22,7 +22,7 @@ namespace currency
   /************************************************************************/
   /*                                                                      */
   /************************************************************************/
-  class simple_wallet : public tools::i_wallet2_callback, 
+  class simple_wallet final : public tools::i_wallet2_callback,
                         public std::enable_shared_from_this<simple_wallet>
   {
   public:
diff --git a/src/wallet/core_default_rpc_proxy.h b/src/wallet/core_default_rpc_proxy.h
index 6ac1b111..ec43ab5f 100644
--- a/src/wallet/core_default_rpc_proxy.h
+++ b/src/wallet/core_default_rpc_proxy.h
@@ -16,7 +16,7 @@
 
 namespace tools
 {
-  class default_http_core_proxy: public i_core_proxy
+  class default_http_core_proxy final : public i_core_proxy
   {
   public:
 
diff --git a/src/wallet/core_rpc_proxy.h b/src/wallet/core_rpc_proxy.h
index 71a06eff..9ea481f2 100644
--- a/src/wallet/core_rpc_proxy.h
+++ b/src/wallet/core_rpc_proxy.h
@@ -16,6 +16,8 @@ namespace tools
   */
   struct i_core_proxy
   {
+    virtual ~i_core_proxy() = default;
+
     virtual bool set_connection_addr(const std::string& url){ return false; }
     virtual bool call_COMMAND_RPC_GET_TX_GLOBAL_OUTPUTS_INDEXES(const currency::COMMAND_RPC_GET_TX_GLOBAL_OUTPUTS_INDEXES::request& rqt, currency::COMMAND_RPC_GET_TX_GLOBAL_OUTPUTS_INDEXES::response& rsp){ return false; }
     virtual bool call_COMMAND_RPC_GET_BLOCKS_FAST(const currency::COMMAND_RPC_GET_BLOCKS_FAST::request& rqt, currency::COMMAND_RPC_GET_BLOCKS_FAST::response& rsp){ return false; }
diff --git a/src/wallet/wallet2.h b/src/wallet/wallet2.h
index 819fde3f..66440855 100644
--- a/src/wallet/wallet2.h
+++ b/src/wallet/wallet2.h
@@ -68,6 +68,8 @@ namespace tools
   class i_wallet2_callback
   {
   public:
+    virtual ~i_wallet2_callback() = default;
+
     virtual void on_new_block(uint64_t /*height*/, const currency::block& /*block*/) {}
     virtual void on_transfer2(const wallet_rpc::wallet_transfer_info& wti, uint64_t balance, uint64_t unlocked_balance, uint64_t total_mined) {}
     virtual void on_pos_block_found(const currency::block& /*block*/) {}
@@ -1204,4 +1206,4 @@ namespace tools
 
 #undef LOG_DEFAULT_CHANNEL 
 #define LOG_DEFAULT_CHANNEL "wallet"
-ENABLE_CHANNEL_BY_DEFAULT("wallet");
\ No newline at end of file
+ENABLE_CHANNEL_BY_DEFAULT("wallet");
diff --git a/tests/core_tests/test_core_proxy.h b/tests/core_tests/test_core_proxy.h
index eaad9e51..83694ecd 100644
--- a/tests/core_tests/test_core_proxy.h
+++ b/tests/core_tests/test_core_proxy.h
@@ -12,6 +12,8 @@
 class test_core_listener
 {
 public:
+  virtual ~test_core_listener() = default;
+
   virtual void before_tx_pushed_to_core(const currency::transaction& tx, const currency::blobdata& blob, currency::core& c, bool invalid_tx = false) {}  // invalid_tx is true when processing a tx, marked as invalid in a test
   virtual void before_block_pushed_to_core(const currency::block& block, const currency::blobdata& blob, currency::core& c) {}
 };