diff --git a/include/boost/unordered/unordered_flat_map.hpp b/include/boost/unordered/unordered_flat_map.hpp
index 04bbc55c..790eb248 100644
--- a/include/boost/unordered/unordered_flat_map.hpp
+++ b/include/boost/unordered/unordered_flat_map.hpp
@@ -32,10 +32,8 @@ namespace boost {
 #pragma warning(disable : 4714) /* marked as __forceinline not inlined */
 #endif
 
-    template <class Key, class T, class Hash, class KeyEqual, class Allocator>
-    class unordered_flat_map
-    {
-      struct map_types
+    namespace detail {
+      template <class Key, class T> struct flat_map_types
       {
         using key_type = Key;
         using raw_key_type = typename std::remove_const<Key>::type;
@@ -78,6 +76,12 @@ namespace boost {
           boost::allocator_destroy(al, p);
         }
       };
+    } // namespace detail
+
+    template <class Key, class T, class Hash, class KeyEqual, class Allocator>
+    class unordered_flat_map
+    {
+      using map_types = detail::flat_map_types<Key, T>;
 
       using table_type = detail::foa::table<map_types, Hash, KeyEqual,
         typename boost::allocator_rebind<Allocator,
diff --git a/include/boost/unordered/unordered_flat_set.hpp b/include/boost/unordered/unordered_flat_set.hpp
index d72eefe0..8c0f2caf 100644
--- a/include/boost/unordered/unordered_flat_set.hpp
+++ b/include/boost/unordered/unordered_flat_set.hpp
@@ -30,10 +30,8 @@ namespace boost {
 #pragma warning(disable : 4714) /* marked as __forceinline not inlined */
 #endif
 
-    template <class Key, class Hash, class KeyEqual, class Allocator>
-    class unordered_flat_set
-    {
-      struct set_types
+    namespace detail {
+      template <class Key> struct flat_set_types
       {
         using key_type = Key;
         using init_type = Key;
@@ -62,6 +60,12 @@ namespace boost {
           boost::allocator_destroy(al, p);
         }
       };
+    } // namespace detail
+
+    template <class Key, class Hash, class KeyEqual, class Allocator>
+    class unordered_flat_set
+    {
+      using set_types = detail::flat_set_types<Key>;
 
       using table_type = detail::foa::table<set_types, Hash, KeyEqual,
         typename boost::allocator_rebind<Allocator,
diff --git a/include/boost/unordered/unordered_node_map.hpp b/include/boost/unordered/unordered_node_map.hpp
index cfa6a021..fd570c76 100644
--- a/include/boost/unordered/unordered_node_map.hpp
+++ b/include/boost/unordered/unordered_node_map.hpp
@@ -33,10 +33,8 @@ namespace boost {
 #pragma warning(disable : 4714) /* marked as __forceinline not inlined */
 #endif
 
-    template <class Key, class T, class Hash, class KeyEqual, class Allocator>
-    class unordered_node_map
-    {
-      struct map_types
+    namespace detail {
+      template <class Key, class T> struct node_map_types
       {
         using key_type = Key;
         using raw_key_type = typename std::remove_const<Key>::type;
@@ -73,7 +71,7 @@ namespace boost {
         template <class A, class... Args>
         static void construct(A& al, storage_type* p, Args&&... args)
         {
-          *p=boost::to_address(boost::allocator_allocate(al, 1));
+          *p = boost::to_address(boost::allocator_allocate(al, 1));
           try {
             boost::allocator_construct(al, *p, std::forward<Args>(args)...);
           } catch (...) {
@@ -96,6 +94,12 @@ namespace boost {
           }
         }
       };
+    } // namespace detail
+
+    template <class Key, class T, class Hash, class KeyEqual, class Allocator>
+    class unordered_node_map
+    {
+      using map_types = detail::node_map_types<Key, T>;
 
       using table_type = detail::foa::table<map_types, Hash, KeyEqual,
         typename boost::allocator_rebind<Allocator,