diff --git a/aether/api_protocol/api_message.h b/aether/api_protocol/api_message.h
index f778e08d..05251322 100644
--- a/aether/api_protocol/api_message.h
+++ b/aether/api_protocol/api_message.h
@@ -20,7 +20,6 @@
 #include <cassert>
 #include <cstdint>
 #include <tuple>
-#include <vector>
 
 #include "aether-miscpp/serialization/serialization.h"
 
@@ -67,8 +66,9 @@ struct Serializer<A, GenericMessage<Ts...>> {
             return res;
           },
           meta.value.fields);
+    } else {
+      return Ok{seri::good};
     }
-    return Ok{seri::good};
   }
 
   SeriResult Deseri(A& archive, Meta<GenericMessage<Ts...>> meta) const {
@@ -81,8 +81,9 @@ struct Serializer<A, GenericMessage<Ts...>> {
             return res;
           },
           meta.value.fields);
+    } else {
+      return Ok{seri::good};
     }
-    return Ok{seri::good};
   }
 };
 }  // namespace seri
diff --git a/aether/config.h b/aether/config.h
index 543cd7da..eacd198e 100644
--- a/aether/config.h
+++ b/aether/config.h
@@ -532,7 +532,7 @@
 #  define AE_EVENT_HANDLER_MAX_SIZE 48
 #endif
 #ifndef AE_EVENT_HANDLER_ALIGN
-#  define AE_EVENT_HANDLER_ALIGN (alignof(void*))
+#  define AE_EVENT_HANDLER_ALIGN (alignof(std::max_align_t))
 #endif
 
 #ifndef NDEBUG
diff --git a/aether/events/event_handler.h b/aether/events/event_handler.h
index 5e1f12b6..22c5c186 100644
--- a/aether/events/event_handler.h
+++ b/aether/events/event_handler.h
@@ -17,6 +17,7 @@
 #ifndef AETHER_EVENTS_EVENT_HANDLER_H_
 #define AETHER_EVENTS_EVENT_HANDLER_H_
 
+#include <cstddef>
 #include <utility>
 
 #include "aether-miscpp/types/small_function.h"
diff --git a/aether/tasks/details/task_queues.h b/aether/tasks/details/task_queues.h
index abec823c..1ccb5567 100644
--- a/aether/tasks/details/task_queues.h
+++ b/aether/tasks/details/task_queues.h
@@ -99,6 +99,8 @@ class TaskQueue : TaskQueueBase<ITask, Capacity, Pool> {
   using base::ReclaimInactive;
 
   bool Add(ITask* p) {
+    // this is contract, p should not be null
+    assert(p != nullptr);
     if (base::list_.size() == base::list_.max_size()) {
       return false;
     }
@@ -139,6 +141,8 @@ class DelayedTaskQueue : TaskQueueBase<IDelayedTask<TP>, Capacity, Pool> {
   using base::ReclaimInactive;
 
   bool Add(IDelayedTask<TP>* p) {
+    // this is contract, p should not be null
+    assert(p != nullptr);
     if (base::list_.size() == base::list_.max_size()) {
       return false;
     }