diff --git a/src/bthread/eloq_module.cpp b/src/bthread/eloq_module.cpp
index 309e457d..71845ead 100644
--- a/src/bthread/eloq_module.cpp
+++ b/src/bthread/eloq_module.cpp
@@ -44,6 +44,13 @@ namespace eloq {
         }
         registered_modules[i] = module;
         registered_module_cnt.fetch_add(1, std::memory_order_release);
+        const auto non_null_modules =
+                std::count_if(registered_modules.begin(), registered_modules.end(),
+                              [](EloqModule *registered_module) {
+                                  return registered_module != nullptr;
+                              });
+        CHECK_EQ(static_cast<int>(non_null_modules),
+                 registered_module_cnt.load(std::memory_order_acquire));
         return 0;
     }
 
@@ -79,7 +86,15 @@ namespace eloq {
             registered_modules[i] = registered_modules[i + 1];
             i++;
         }
+        registered_modules[registered_modules.size() - 1] = nullptr;
         registered_module_cnt.fetch_sub(1, std::memory_order_release);
+        const auto non_null_modules =
+                std::count_if(registered_modules.begin(), registered_modules.end(),
+                              [](EloqModule *registered_module) {
+                                  return registered_module != nullptr;
+                              });
+        CHECK_EQ(static_cast<int>(non_null_modules),
+                 registered_module_cnt.load(std::memory_order_acquire));
         lk.unlock();
 
         while (module->registered_workers_.load(std::memory_order_acquire) != 0) {
diff --git a/src/bthread/task_group.cpp b/src/bthread/task_group.cpp
index e58d2a4e..3126bfc3 100644
--- a/src/bthread/task_group.cpp
+++ b/src/bthread/task_group.cpp
@@ -1318,12 +1318,15 @@ bool TaskGroup::HasTasks() {
 void TaskGroup::CheckAndUpdateModules() {
     if (modules_cnt_ != registered_module_cnt.load(std::memory_order_acquire)) {
         std::shared_lock lk(eloq::module_mutex);
+        const int registered_module_count =
+                registered_module_cnt.load(std::memory_order_acquire);
         const auto old_registered_modules = registered_modules_;
         registered_modules_ = registered_modules;
         lk.unlock();
         const auto new_module_cnt = std::count_if(registered_modules_.begin(), registered_modules_.end(), [](eloq::EloqModule* module) {
             return module != nullptr;
         });
+        CHECK_EQ(static_cast<int>(new_module_cnt), registered_module_count);
         // new modules
         for (auto i = modules_cnt_; i < new_module_cnt; ++i) {
             registered_modules_[i]->registered_workers_.fetch_add(1, std::memory_order_relaxed);