diff --git a/libraries/plugins/account_history/account_history_plugin.cpp b/libraries/plugins/account_history/account_history_plugin.cpp
index 19e384a171..dd8a5c6215 100644
--- a/libraries/plugins/account_history/account_history_plugin.cpp
+++ b/libraries/plugins/account_history/account_history_plugin.cpp
@@ -46,7 +46,7 @@ namespace detail
 class account_history_plugin_impl
 {
    public:
-      account_history_plugin_impl(account_history_plugin& _plugin)
+      explicit account_history_plugin_impl(account_history_plugin& _plugin)
          : _self( _plugin )
       { }
 
@@ -60,6 +60,9 @@ class account_history_plugin_impl
          return _self.database();
       }
 
+      friend class graphene::account_history::account_history_plugin;
+
+   private:
       account_history_plugin& _self;
       flat_set<account_id_type> _tracked_accounts;
       flat_set<account_id_type> _extended_history_accounts;
@@ -68,7 +71,7 @@ class account_history_plugin_impl
       primary_index< operation_history_index >* _oho_index;
       uint64_t _max_ops_per_account = -1;
       uint64_t _extended_max_ops_per_account = -1;
-   private:
+
       /** add one history record, then check and remove the earliest history record */
       void add_account_history( const account_id_type account_id, const operation_history_id_type op_id );
 
@@ -279,11 +282,10 @@ account_history_plugin::account_history_plugin(graphene::app::application& app)
    plugin(app),
    my( std::make_unique<detail::account_history_plugin_impl>(*this) )
 {
+   // Nothing else to do
 }
 
-account_history_plugin::~account_history_plugin()
-{
-}
+account_history_plugin::~account_history_plugin() = default;
 
 std::string account_history_plugin::plugin_name()const
 {
diff --git a/libraries/plugins/account_history/include/graphene/account_history/account_history_plugin.hpp b/libraries/plugins/account_history/include/graphene/account_history/account_history_plugin.hpp
index 9676869fbf..6ceda572a7 100644
--- a/libraries/plugins/account_history/include/graphene/account_history/account_history_plugin.hpp
+++ b/libraries/plugins/account_history/include/graphene/account_history/account_history_plugin.hpp
@@ -64,7 +64,7 @@ namespace detail
 class account_history_plugin : public graphene::app::plugin
 {
    public:
-      account_history_plugin(graphene::app::application& app);
+      explicit account_history_plugin(graphene::app::application& app);
       ~account_history_plugin() override;
 
       std::string plugin_name()const override;
@@ -76,7 +76,7 @@ class account_history_plugin : public graphene::app::plugin
 
       flat_set<account_id_type> tracked_accounts()const;
 
-      friend class detail::account_history_plugin_impl;
+   private:
       std::unique_ptr<detail::account_history_plugin_impl> my;
 };
 
diff --git a/libraries/plugins/api_helper_indexes/api_helper_indexes.cpp b/libraries/plugins/api_helper_indexes/api_helper_indexes.cpp
index 00fbbf3e16..79c996399c 100644
--- a/libraries/plugins/api_helper_indexes/api_helper_indexes.cpp
+++ b/libraries/plugins/api_helper_indexes/api_helper_indexes.cpp
@@ -133,7 +133,7 @@ namespace detail
 class api_helper_indexes_impl
 {
    public:
-      api_helper_indexes_impl(api_helper_indexes& _plugin)
+      explicit api_helper_indexes_impl(api_helper_indexes& _plugin)
          : _self( _plugin )
       {  }
 
@@ -142,10 +142,8 @@ class api_helper_indexes_impl
          return _self.database();
       }
 
-      api_helper_indexes& _self;
-
    private:
-
+      api_helper_indexes& _self;
 };
 
 } // end namespace detail
@@ -154,11 +152,10 @@ api_helper_indexes::api_helper_indexes(graphene::app::application& app) :
    plugin(app),
    my( std::make_unique<detail::api_helper_indexes_impl>(*this) )
 {
+   // Nothing else to do
 }
 
-api_helper_indexes::~api_helper_indexes()
-{
-}
+api_helper_indexes::~api_helper_indexes() = default;
 
 std::string api_helper_indexes::plugin_name()const
 {
diff --git a/libraries/plugins/api_helper_indexes/include/graphene/api_helper_indexes/api_helper_indexes.hpp b/libraries/plugins/api_helper_indexes/include/graphene/api_helper_indexes/api_helper_indexes.hpp
index a6bb59b307..bfd7502ab1 100644
--- a/libraries/plugins/api_helper_indexes/include/graphene/api_helper_indexes/api_helper_indexes.hpp
+++ b/libraries/plugins/api_helper_indexes/include/graphene/api_helper_indexes/api_helper_indexes.hpp
@@ -79,7 +79,7 @@ namespace detail
 class api_helper_indexes : public graphene::app::plugin
 {
    public:
-      api_helper_indexes(graphene::app::application& app);
+      explicit api_helper_indexes(graphene::app::application& app);
       ~api_helper_indexes() override;
 
       std::string plugin_name()const override;
diff --git a/libraries/plugins/custom_operations/custom_operations_plugin.cpp b/libraries/plugins/custom_operations/custom_operations_plugin.cpp
index 1696b98f50..e9fb5b971c 100644
--- a/libraries/plugins/custom_operations/custom_operations_plugin.cpp
+++ b/libraries/plugins/custom_operations/custom_operations_plugin.cpp
@@ -35,10 +35,9 @@ namespace detail
 class custom_operations_plugin_impl
 {
    public:
-   custom_operations_plugin_impl(custom_operations_plugin& _plugin)
+      explicit custom_operations_plugin_impl(custom_operations_plugin& _plugin)
          : _self( _plugin )
       {  }
-      virtual ~custom_operations_plugin_impl();
 
       void onBlock();
 
@@ -47,12 +46,12 @@ class custom_operations_plugin_impl
          return _self.database();
       }
 
-      custom_operations_plugin& _self;
-
-      uint32_t _start_block = 45000000;
+      friend class graphene::custom_operations::custom_operations_plugin;
 
    private:
+      custom_operations_plugin& _self;
 
+      uint32_t _start_block = 45000000;
 };
 
 struct custom_op_visitor
@@ -98,22 +97,16 @@ void custom_operations_plugin_impl::onBlock()
    }
 }
 
-custom_operations_plugin_impl::~custom_operations_plugin_impl()
-{
-   // nothing to do
-}
-
 } // end namespace detail
 
 custom_operations_plugin::custom_operations_plugin(graphene::app::application& app) :
    plugin(app),
    my( std::make_unique<detail::custom_operations_plugin_impl>(*this) )
 {
+   // Nothing to do
 }
 
-custom_operations_plugin::~custom_operations_plugin()
-{
-}
+custom_operations_plugin::~custom_operations_plugin() = default;
 
 std::string custom_operations_plugin::plugin_name()const
 {
diff --git a/libraries/plugins/custom_operations/include/graphene/custom_operations/custom_operations_plugin.hpp b/libraries/plugins/custom_operations/include/graphene/custom_operations/custom_operations_plugin.hpp
index e2a5fd9633..add8ce8637 100644
--- a/libraries/plugins/custom_operations/include/graphene/custom_operations/custom_operations_plugin.hpp
+++ b/libraries/plugins/custom_operations/include/graphene/custom_operations/custom_operations_plugin.hpp
@@ -41,7 +41,7 @@ namespace detail
 class custom_operations_plugin : public graphene::app::plugin
 {
    public:
-      custom_operations_plugin(graphene::app::application& app);
+      explicit custom_operations_plugin(graphene::app::application& app);
       ~custom_operations_plugin() override;
 
       std::string plugin_name()const override;
@@ -52,7 +52,7 @@ class custom_operations_plugin : public graphene::app::plugin
       void plugin_initialize(const boost::program_options::variables_map& options) override;
       void plugin_startup() override;
 
-      friend class detail::custom_operations_plugin_impl;
+   private:
       std::unique_ptr<detail::custom_operations_plugin_impl> my;
 };
 
diff --git a/libraries/plugins/delayed_node/delayed_node_plugin.cpp b/libraries/plugins/delayed_node/delayed_node_plugin.cpp
index 18ef6b26b1..b16aadd233 100644
--- a/libraries/plugins/delayed_node/delayed_node_plugin.cpp
+++ b/libraries/plugins/delayed_node/delayed_node_plugin.cpp
@@ -47,17 +47,18 @@ struct delayed_node_plugin_impl {
 }
 
 delayed_node_plugin::delayed_node_plugin(graphene::app::application& app) :
-   plugin(app),
-   my(nullptr)
-{}
+   plugin(app)
+{
+   // Nothing else to do
+}
 
-delayed_node_plugin::~delayed_node_plugin()
-{}
+delayed_node_plugin::~delayed_node_plugin() = default;
 
 void delayed_node_plugin::plugin_set_program_options(bpo::options_description& cli, bpo::options_description& cfg)
 {
    cli.add_options()
-         ("trusted-node", boost::program_options::value<std::string>(), "RPC endpoint of a trusted validating node (required for delayed_node)")
+         ("trusted-node", boost::program_options::value<std::string>(),
+          "RPC endpoint of a trusted validating node (required for delayed_node)")
          ;
    cfg.add(cli);
 }
diff --git a/libraries/plugins/delayed_node/include/graphene/delayed_node/delayed_node_plugin.hpp b/libraries/plugins/delayed_node/include/graphene/delayed_node/delayed_node_plugin.hpp
index 4e06c7fcfc..448d979782 100644
--- a/libraries/plugins/delayed_node/include/graphene/delayed_node/delayed_node_plugin.hpp
+++ b/libraries/plugins/delayed_node/include/graphene/delayed_node/delayed_node_plugin.hpp
@@ -32,12 +32,12 @@ class delayed_node_plugin : public graphene::app::plugin
 {
    std::unique_ptr<detail::delayed_node_plugin_impl> my;
 public:
-   delayed_node_plugin(graphene::app::application& app);
+   explicit delayed_node_plugin(graphene::app::application& app);
    ~delayed_node_plugin() override;
 
    std::string plugin_name()const override { return "delayed_node"; }
    void plugin_set_program_options(boost::program_options::options_description&,
-                                           boost::program_options::options_description& cfg) override;
+                                   boost::program_options::options_description& cfg) override;
    void plugin_initialize(const boost::program_options::variables_map& options) override;
    void plugin_startup() override;
    void mainloop();
diff --git a/libraries/plugins/elasticsearch/elasticsearch_plugin.cpp b/libraries/plugins/elasticsearch/elasticsearch_plugin.cpp
index 4eaa6643e9..d583afccc0 100644
--- a/libraries/plugins/elasticsearch/elasticsearch_plugin.cpp
+++ b/libraries/plugins/elasticsearch/elasticsearch_plugin.cpp
@@ -36,7 +36,7 @@ namespace detail
 class elasticsearch_plugin_impl
 {
    public:
-      elasticsearch_plugin_impl(elasticsearch_plugin& _plugin)
+      explicit elasticsearch_plugin_impl(elasticsearch_plugin& _plugin)
          : _self( _plugin )
       {
          curl = curl_easy_init();
@@ -102,7 +102,6 @@ elasticsearch_plugin_impl::~elasticsearch_plugin_impl()
       curl_easy_cleanup(curl);
       curl = nullptr;
    }
-   return;
 }
 
 bool elasticsearch_plugin_impl::update_account_histories( const signed_block& b )
@@ -437,11 +436,10 @@ elasticsearch_plugin::elasticsearch_plugin(graphene::app::application& app) :
    plugin(app),
    my( std::make_unique<detail::elasticsearch_plugin_impl>(*this) )
 {
+   // Nothing else to do
 }
 
-elasticsearch_plugin::~elasticsearch_plugin()
-{
-}
+elasticsearch_plugin::~elasticsearch_plugin() = default;
 
 std::string elasticsearch_plugin::plugin_name()const
 {
diff --git a/libraries/plugins/elasticsearch/include/graphene/elasticsearch/elasticsearch_plugin.hpp b/libraries/plugins/elasticsearch/include/graphene/elasticsearch/elasticsearch_plugin.hpp
index 61f385efa0..fbd8366b3f 100644
--- a/libraries/plugins/elasticsearch/include/graphene/elasticsearch/elasticsearch_plugin.hpp
+++ b/libraries/plugins/elasticsearch/include/graphene/elasticsearch/elasticsearch_plugin.hpp
@@ -55,7 +55,7 @@ enum mode { only_save = 0 , only_query = 1, all = 2 };
 class elasticsearch_plugin : public graphene::app::plugin
 {
    public:
-      elasticsearch_plugin(graphene::app::application& app);
+      explicit elasticsearch_plugin(graphene::app::application& app);
       ~elasticsearch_plugin() override;
 
       std::string plugin_name()const override;
diff --git a/libraries/plugins/es_objects/es_objects.cpp b/libraries/plugins/es_objects/es_objects.cpp
index e538edd370..2e0fd4613e 100644
--- a/libraries/plugins/es_objects/es_objects.cpp
+++ b/libraries/plugins/es_objects/es_objects.cpp
@@ -41,7 +41,7 @@ namespace detail
 class es_objects_plugin_impl
 {
    public:
-      es_objects_plugin_impl(es_objects_plugin& _plugin)
+      explicit es_objects_plugin_impl(es_objects_plugin& _plugin)
          : _self( _plugin )
       {
          curl = curl_easy_init();
@@ -269,7 +269,6 @@ es_objects_plugin_impl::~es_objects_plugin_impl()
       curl_easy_cleanup(curl);
       curl = nullptr;
    }
-   return;
 }
 
 } // end namespace detail
@@ -278,11 +277,10 @@ es_objects_plugin::es_objects_plugin(graphene::app::application& app) :
    plugin(app),
    my( std::make_unique<detail::es_objects_plugin_impl>(*this) )
 {
+   // Nothing else to do
 }
 
-es_objects_plugin::~es_objects_plugin()
-{
-}
+es_objects_plugin::~es_objects_plugin() = default;
 
 std::string es_objects_plugin::plugin_name()const
 {
diff --git a/libraries/plugins/es_objects/include/graphene/es_objects/es_objects.hpp b/libraries/plugins/es_objects/include/graphene/es_objects/es_objects.hpp
index b9bc339681..dff4812498 100644
--- a/libraries/plugins/es_objects/include/graphene/es_objects/es_objects.hpp
+++ b/libraries/plugins/es_objects/include/graphene/es_objects/es_objects.hpp
@@ -38,8 +38,8 @@ namespace detail
 class es_objects_plugin : public graphene::app::plugin
 {
    public:
-      es_objects_plugin(graphene::app::application& app);
-      ~es_objects_plugin();
+      explicit es_objects_plugin(graphene::app::application& app);
+      ~es_objects_plugin() override;
 
       std::string plugin_name()const override;
       std::string plugin_description()const override;
@@ -49,7 +49,7 @@ class es_objects_plugin : public graphene::app::plugin
       void plugin_initialize(const boost::program_options::variables_map& options) override;
       void plugin_startup() override;
 
-      friend class detail::es_objects_plugin_impl;
+   private:
       std::unique_ptr<detail::es_objects_plugin_impl> my;
 };
 
diff --git a/libraries/plugins/grouped_orders/grouped_orders_plugin.cpp b/libraries/plugins/grouped_orders/grouped_orders_plugin.cpp
index da655026fd..b745ea494c 100644
--- a/libraries/plugins/grouped_orders/grouped_orders_plugin.cpp
+++ b/libraries/plugins/grouped_orders/grouped_orders_plugin.cpp
@@ -34,9 +34,8 @@ namespace detail
 class grouped_orders_plugin_impl
 {
    public:
-      grouped_orders_plugin_impl(grouped_orders_plugin& _plugin)
+      explicit grouped_orders_plugin_impl(grouped_orders_plugin& _plugin)
       :_self( _plugin ) {}
-      virtual ~grouped_orders_plugin_impl();
 
       graphene::chain::database& database()
       {
@@ -235,9 +234,6 @@ void limit_order_group_index::remove_order( const limit_order_object& o, bool re
    }
 }
 
-grouped_orders_plugin_impl::~grouped_orders_plugin_impl()
-{}
-
 } // end namespace detail
 
 
@@ -245,11 +241,10 @@ grouped_orders_plugin::grouped_orders_plugin(graphene::app::application& app) :
    plugin(app),
    my( std::make_unique<detail::grouped_orders_plugin_impl>(*this) )
 {
+   // Nothing else to do
 }
 
-grouped_orders_plugin::~grouped_orders_plugin()
-{
-}
+grouped_orders_plugin::~grouped_orders_plugin() = default;
 
 std::string grouped_orders_plugin::plugin_name()const
 {
diff --git a/libraries/plugins/grouped_orders/include/graphene/grouped_orders/grouped_orders_plugin.hpp b/libraries/plugins/grouped_orders/include/graphene/grouped_orders/grouped_orders_plugin.hpp
index 637e6e7925..4a0e4452ea 100644
--- a/libraries/plugins/grouped_orders/include/graphene/grouped_orders/grouped_orders_plugin.hpp
+++ b/libraries/plugins/grouped_orders/include/graphene/grouped_orders/grouped_orders_plugin.hpp
@@ -69,7 +69,7 @@ namespace detail
 class grouped_orders_plugin : public graphene::app::plugin
 {
    public:
-      grouped_orders_plugin(graphene::app::application& app);
+      explicit grouped_orders_plugin(graphene::app::application& app);
       ~grouped_orders_plugin() override;
 
       std::string plugin_name()const override;
@@ -85,7 +85,6 @@ class grouped_orders_plugin : public graphene::app::plugin
       const map< limit_order_group_key, limit_order_group_data >& limit_order_groups();
 
    private:
-      friend class detail::grouped_orders_plugin_impl;
       std::unique_ptr<detail::grouped_orders_plugin_impl> my;
 };
 
diff --git a/libraries/plugins/market_history/include/graphene/market_history/market_history_plugin.hpp b/libraries/plugins/market_history/include/graphene/market_history/market_history_plugin.hpp
index 4021dad75e..bc70ae8794 100644
--- a/libraries/plugins/market_history/include/graphene/market_history/market_history_plugin.hpp
+++ b/libraries/plugins/market_history/include/graphene/market_history/market_history_plugin.hpp
@@ -380,7 +380,7 @@ namespace detail
 class market_history_plugin : public graphene::app::plugin
 {
    public:
-      market_history_plugin(graphene::app::application& app);
+      explicit market_history_plugin(graphene::app::application& app);
       ~market_history_plugin() override;
 
       std::string plugin_name()const override;
@@ -397,7 +397,6 @@ class market_history_plugin : public graphene::app::plugin
       uint32_t                    max_order_his_seconds_per_market()const;
 
    private:
-      friend class detail::market_history_plugin_impl;
       std::unique_ptr<detail::market_history_plugin_impl> my;
 };
 
diff --git a/libraries/plugins/market_history/market_history_plugin.cpp b/libraries/plugins/market_history/market_history_plugin.cpp
index f9211d1d36..adca4f5b77 100644
--- a/libraries/plugins/market_history/market_history_plugin.cpp
+++ b/libraries/plugins/market_history/market_history_plugin.cpp
@@ -43,9 +43,8 @@ namespace detail
 class market_history_plugin_impl
 {
    public:
-      market_history_plugin_impl(market_history_plugin& _plugin)
+      explicit market_history_plugin_impl(market_history_plugin& _plugin)
       :_self( _plugin ) {}
-      virtual ~market_history_plugin_impl();
 
       /** this method is called as a callback after a block is applied
        * and will process/index all operations that were applied in the block.
@@ -294,9 +293,6 @@ struct operation_process_fill_order
    }
 };
 
-market_history_plugin_impl::~market_history_plugin_impl()
-{}
-
 void market_history_plugin_impl::update_market_histories( const signed_block& b )
 {
    graphene::chain::database& db = database();
@@ -731,19 +727,14 @@ void market_history_plugin_impl::update_liquidity_pool_histories(
 } // end namespace detail
 
 
-
-
-
-
 market_history_plugin::market_history_plugin(graphene::app::application& app) :
    plugin(app),
    my( std::make_unique<detail::market_history_plugin_impl>(*this) )
 {
+   // Nothing else to do
 }
 
-market_history_plugin::~market_history_plugin()
-{
-}
+market_history_plugin::~market_history_plugin() = default;
 
 std::string market_history_plugin::plugin_name()const
 {
diff --git a/libraries/plugins/template_plugin/include/graphene/template_plugin/template_plugin.hpp b/libraries/plugins/template_plugin/include/graphene/template_plugin/template_plugin.hpp
index 12d4ae4d1e..b9ccee9b79 100644
--- a/libraries/plugins/template_plugin/include/graphene/template_plugin/template_plugin.hpp
+++ b/libraries/plugins/template_plugin/include/graphene/template_plugin/template_plugin.hpp
@@ -52,7 +52,7 @@ namespace detail
 class template_plugin : public graphene::app::plugin
 {
    public:
-      template_plugin(graphene::app::application& app);
+      explicit template_plugin(graphene::app::application& app);
       ~template_plugin() override;
 
       std::string plugin_name()const override;
@@ -64,7 +64,6 @@ class template_plugin : public graphene::app::plugin
       void plugin_startup() override;
       void plugin_shutdown() override;
 
-      friend class detail::template_plugin_impl;
    private:
       void cleanup();
       std::unique_ptr<detail::template_plugin_impl> my;
diff --git a/libraries/plugins/template_plugin/template_plugin.cpp b/libraries/plugins/template_plugin/template_plugin.cpp
index 3f96a79081..72020a8588 100644
--- a/libraries/plugins/template_plugin/template_plugin.cpp
+++ b/libraries/plugins/template_plugin/template_plugin.cpp
@@ -32,9 +32,7 @@ namespace detail
 class template_plugin_impl
 {
    public:
-      template_plugin_impl(template_plugin& _plugin)
-         : _self( _plugin )
-      {  }
+      explicit template_plugin_impl( template_plugin& _plugin );
       virtual ~template_plugin_impl();
 
       void on_block( const signed_block& b );
@@ -44,12 +42,13 @@ class template_plugin_impl
          return _self.database();
       }
 
+      friend class graphene::template_plugin::template_plugin;
+
+   private:
       template_plugin& _self;
 
       std::string _plugin_option = "";
 
-   private:
-
 };
 
 void template_plugin_impl::on_block( const signed_block& b )
@@ -57,9 +56,15 @@ void template_plugin_impl::on_block( const signed_block& b )
    wdump((b.block_num()));
 }
 
+template_plugin_impl::template_plugin_impl( template_plugin& _plugin ) :
+   _self( _plugin )
+{
+   // Put other code here
+}
+
 template_plugin_impl::~template_plugin_impl()
 {
-   // Put the real code here
+   // Put the real code here. If none, remove the destructor.
 }
 
 } // end namespace detail