diff --git a/Adapter.cc b/Adapter.cc
index 47cfaae..86ad5db 100644
--- a/Adapter.cc
+++ b/Adapter.cc
@@ -78,8 +78,9 @@ namespace pEp {
             SYNC_EVENT syncEvent = nullptr;
             const bool success = sync_evt_q.try_pop_front(syncEvent, std::chrono::seconds(threshold));
 
-            if (!success)
+            if (!success) {
                 return new_sync_timeout_event();
+            }
 
             return syncEvent;
         }
@@ -98,8 +99,9 @@ namespace pEp {
 
             switch (action) {
                 case release:
-                    if (_session.get())
+                    if (_session.get()) {
                         _session = nullptr;
+                    }
                     break;
 
                 case init:
@@ -143,10 +145,11 @@ namespace pEp {
             catch (std::underflow_error&) {
                 return false;
             }
-            if (ev)
+            if (ev) {
                 return false;
-            else
+            } else {
                 return true;
+            }
        }
     }
 }
diff --git a/Adapter.hxx b/Adapter.hxx
index 9718cde..4bd2544 100644
--- a/Adapter.hxx
+++ b/Adapter.hxx
@@ -30,8 +30,9 @@ namespace pEp {
             _ex = nullptr;
             assert(_messageToSend);
             assert(_notifyHandshake);
-            if (obj && _startup)
+            if (obj && _startup) {
                 _startup(obj);
+            }
 
             session();
 
@@ -56,8 +57,9 @@ namespace pEp {
 
             session(release);
 
-            if (obj && _shutdown)
+            if (obj && _shutdown) {
                 _shutdown(obj);
+            }
         }
 
         template< class T >
@@ -68,22 +70,26 @@ namespace pEp {
             function< void(T *) > _startup,
             function< void(T *) > _shutdown)
         {
-            if (messageToSend)
+            if (messageToSend) {
                 _messageToSend = messageToSend;
+            }
 
-            if (notifyHandshake)
+            if (notifyHandshake) {
                 _notifyHandshake = notifyHandshake;
+            }
 
             session();
 
             if (!_sync_thread.joinable()) {
                 register_done = false;
                 _sync_thread = std::thread(sync_thread<T>, obj, _startup, _shutdown);
-                while (!register_done)
+                while (!register_done) {
                     std::this_thread::sleep_for(std::chrono::milliseconds(100));
+                }
 
-                if (_ex)
+                if (_ex) {
                     std::rethrow_exception(_ex);
+                }
             }
         }
     }
diff --git a/callback_dispatcher.cc b/callback_dispatcher.cc
index 08bf769..704017d 100644
--- a/callback_dispatcher.cc
+++ b/callback_dispatcher.cc
@@ -25,8 +25,9 @@ namespace pEp {
         )
     {
         assert(messageToSend);
-        if (!messageToSend)
+        if (!messageToSend) {
             throw std::invalid_argument("messageToSend must be set");
+        }
 
         targets.push_back({messageToSend, notifyHandshake, on_startup, shutdown});
     }
@@ -34,8 +35,9 @@ namespace pEp {
     void CallbackDispatcher::remove(::messageToSend_t messageToSend)
     {
         assert(messageToSend);
-        if (!messageToSend)
+        if (!messageToSend) {
             throw std::invalid_argument("messageToSend argument needed");
+        }
 
         for (auto target = targets.begin(); target != targets.end(); ++target) {
             if (target->messageToSend == messageToSend) {
@@ -43,23 +45,27 @@ namespace pEp {
                 break;
             }
         }
-        if (targets.empty())
+
+        if (targets.empty()) {
             stop_sync();
+        }
     }
 
     void CallbackDispatcher::on_startup()
     {
         for (auto target : targets) {
-            if (target.on_startup)
+            if (target.on_startup) {
                 target.on_startup();
+            }
         }
     }
 
     void CallbackDispatcher::on_shutdown()
     {
         for (auto target : targets) {
-            if (target.on_shutdown)
+            if (target.on_shutdown) {
                 target.on_shutdown();
+            }
         }
     }
 
@@ -73,8 +79,9 @@ namespace pEp {
                 &CallbackDispatcher::on_shutdown);
 
         for (auto target : callback_dispatcher.targets) {
-            if (target.notifyHandshake)
+            if (target.notifyHandshake) {
                 target.notifyHandshake(nullptr, nullptr, SYNC_NOTIFY_START);
+            }
         }
     }
 
@@ -85,8 +92,9 @@ namespace pEp {
         callback_dispatcher.semaphore.go();
 
         for (auto target : callback_dispatcher.targets) {
-            if (target.notifyHandshake)
+            if (target.notifyHandshake) {
                 target.notifyHandshake(nullptr, nullptr, SYNC_NOTIFY_STOP);
+            }
         }
     }
 
@@ -95,14 +103,16 @@ namespace pEp {
         if (Adapter::on_sync_thread() && !msg) {
             semaphore.try_wait();
 
-            if (Adapter::in_shutdown())
+            if (Adapter::in_shutdown()) {
                 return PEP_SYNC_NO_CHANNEL;
+            }
 
             PEP_STATUS status = PassphraseCache::config_next_passphrase();
 
             // if the cache has no valid passphrase ask the app
-            if (status == PEP_PASSPHRASE_REQUIRED || status == PEP_WRONG_PASSPHRASE)
+            if (status == PEP_PASSPHRASE_REQUIRED || status == PEP_WRONG_PASSPHRASE) {
                 semaphore.stop();
+            }
 
             // the pEp engine must try again
             return status;
@@ -117,8 +127,9 @@ namespace pEp {
             ::message *_msg = nullptr;
             if (msg) {
                 _msg = ::message_dup(msg);
-                if (!_msg)
+                if (!_msg) {
                     return PEP_OUT_OF_MEMORY;
+                }
             }
             assert(target.messageToSend);
             target.messageToSend(_msg);
@@ -135,8 +146,9 @@ namespace pEp {
                 ::pEp_identity *_me = nullptr;
                 if (me) {
                     _me = ::identity_dup(me);
-                    if (!_me)
+                    if (!_me) {
                         return PEP_OUT_OF_MEMORY;
+                    }
                 }
                 ::pEp_identity *_partner = nullptr;
                 if (partner) {
diff --git a/callback_dispatcher.hh b/callback_dispatcher.hh
index 17f39e3..818f5ef 100644
--- a/callback_dispatcher.hh
+++ b/callback_dispatcher.hh
@@ -27,30 +27,36 @@ namespace pEp {
 
     public:
         void add(
-                ::messageToSend_t messageToSend,
-                ::notifyHandshake_t notifyHandshake,
-                proc on_startup = nullptr,
-                proc on_shutdown = nullptr
-            );
+            ::messageToSend_t messageToSend,
+            ::notifyHandshake_t notifyHandshake,
+            proc on_startup = nullptr,
+            proc on_shutdown = nullptr
+        );
         void remove(::messageToSend_t messageToSend);
 
         static void start_sync();
         static void stop_sync();
 
         static PEP_STATUS messageToSend(::message *msg);
-        static PEP_STATUS notifyHandshake(::pEp_identity *me,
-                ::pEp_identity *partner, ::sync_handshake_signal signal);
+        static PEP_STATUS notifyHandshake(
+            ::pEp_identity *me,
+            ::pEp_identity *partner,
+            ::sync_handshake_signal signal
+        );
     protected:
         void on_startup();
         void on_shutdown();
 
         PEP_STATUS _messageToSend(::message *msg);
-        PEP_STATUS _notifyHandshake(::pEp_identity *me,
-                ::pEp_identity *partner, ::sync_handshake_signal signal);
+        PEP_STATUS _notifyHandshake(
+            ::pEp_identity *me,
+            ::pEp_identity *partner,
+            ::sync_handshake_signal signal
+        );
 
         friend const char *PassphraseCache::add(const std::string& passphrase);
     };
 
     extern CallbackDispatcher callback_dispatcher;
-};
+}