diff --git a/include/boost/unordered/unordered_flat_map.hpp b/include/boost/unordered/unordered_flat_map.hpp
index 9f077d7a..3bb3122b 100644
--- a/include/boost/unordered/unordered_flat_map.hpp
+++ b/include/boost/unordered/unordered_flat_map.hpp
@@ -51,14 +51,6 @@ namespace boost {
       using iterator = typename table_type::iterator;
       using const_iterator = typename table_type::const_iterator;
 
-      iterator begin() noexcept { return table_.begin(); }
-      const_iterator begin() const noexcept { return table_.begin(); }
-      const_iterator cbegin() const noexcept { return table_.cbegin(); }
-
-      iterator end() noexcept { return table_.end(); }
-      const_iterator end() const noexcept { return table_.end(); }
-      const_iterator cend() const noexcept { return table_.cend(); }
-
       unordered_flat_map() : unordered_flat_map(0) {}
 
       explicit unordered_flat_map(size_type n, hasher const& h = hasher(),
@@ -68,6 +60,16 @@ namespace boost {
       {
       }
 
+      unordered_flat_map(size_type n, allocator_type const& a)
+          : unordered_flat_map(n, hasher(), key_equal(), a)
+      {
+      }
+
+      explicit unordered_flat_map(allocator_type const& a)
+          : unordered_flat_map(0, a)
+      {
+      }
+
       template <class Iterator>
       unordered_flat_map(Iterator first, Iterator last, size_type n = 0,
         hasher const& h = hasher(), key_equal const& pred = key_equal(),
@@ -77,6 +79,30 @@ namespace boost {
         this->insert(first, last);
       }
 
+      unordered_flat_map(std::initializer_list<value_type> ilist,
+        size_type n = 0, hasher const& h = hasher(),
+        key_equal const& pred = key_equal(),
+        allocator_type const& a = allocator_type())
+          : unordered_flat_map(ilist.begin(), ilist.end(), n, h, pred, a)
+      {
+      }
+
+      allocator_type get_allocator() const noexcept
+      {
+        return table_.get_allocator();
+      }
+
+      /// Iterators
+      ///
+
+      iterator begin() noexcept { return table_.begin(); }
+      const_iterator begin() const noexcept { return table_.begin(); }
+      const_iterator cbegin() const noexcept { return table_.cbegin(); }
+
+      iterator end() noexcept { return table_.end(); }
+      const_iterator end() const noexcept { return table_.end(); }
+      const_iterator cend() const noexcept { return table_.cend(); }
+
       /// Capacity
       ///
 
@@ -246,6 +272,9 @@ namespace boost {
         return {pos, next};
       }
 
+      /// Hash Policy
+      ///
+
       size_type bucket_count() const noexcept { return table_.capacity(); }
 
       float load_factor() const noexcept { return table_.load_factor(); }
@@ -255,6 +284,13 @@ namespace boost {
         return table_.max_load_factor();
       }
 
+      void max_load_factor(float) {}
+
+      /// Observers
+      ///
+
+      hasher hash_function() const { return table_.hash_function(); }
+
       key_equal key_eq() const { return table_.key_eq(); }
     };
   } // namespace unordered
diff --git a/include/boost/unordered/unordered_flat_set.hpp b/include/boost/unordered/unordered_flat_set.hpp
index cec24f18..c7bed6fc 100644
--- a/include/boost/unordered/unordered_flat_set.hpp
+++ b/include/boost/unordered/unordered_flat_set.hpp
@@ -59,6 +59,16 @@ namespace boost {
       {
       }
 
+      unordered_flat_set(size_type n, allocator_type const& a)
+          : unordered_flat_set(n, hasher(), key_equal(), a)
+      {
+      }
+
+      explicit unordered_flat_set(allocator_type const& a)
+          : unordered_flat_set(0, a)
+      {
+      }
+
       template <class Iterator>
       unordered_flat_set(Iterator first, Iterator last, size_type n = 0,
         hasher const& h = hasher(), key_equal const& pred = key_equal(),
@@ -68,6 +78,22 @@ namespace boost {
         this->insert(first, last);
       }
 
+      unordered_flat_set(std::initializer_list<value_type> ilist,
+        size_type n = 0, hasher const& h = hasher(),
+        key_equal const& pred = key_equal(),
+        allocator_type const& a = allocator_type())
+          : unordered_flat_set(ilist.begin(), ilist.end(), n, h, pred, a)
+      {
+      }
+
+      allocator_type get_allocator() const noexcept
+      {
+        return table_.get_allocator();
+      }
+
+      /// Iterators
+      ///
+
       iterator begin() noexcept { return table_.begin(); }
       const_iterator begin() const noexcept { return table_.begin(); }
       const_iterator cbegin() const noexcept { return table_.cbegin(); }
@@ -173,6 +199,9 @@ namespace boost {
         return {pos, next};
       }
 
+      /// Hash Policy
+      ///
+
       size_type bucket_count() const noexcept { return table_.capacity(); }
 
       float load_factor() const noexcept { return table_.load_factor(); }
@@ -182,6 +211,13 @@ namespace boost {
         return table_.max_load_factor();
       }
 
+      void max_load_factor(float) {}
+
+      /// Observers
+      ///
+
+      hasher hash_function() const { return table_.hash_function(); }
+
       key_equal key_eq() const { return table_.key_eq(); }
     };
   } // namespace unordered
diff --git a/test/Jamfile.v2 b/test/Jamfile.v2
index bee68b6c..b07b2313 100644
--- a/test/Jamfile.v2
+++ b/test/Jamfile.v2
@@ -48,6 +48,7 @@ run unordered/incomplete_test.cpp ;
 run unordered/simple_tests.cpp ;
 run unordered/equivalent_keys_tests.cpp ;
 run unordered/constructor_tests.cpp ;
+run unordered/constructor_tests.cpp : : : $(CPP14) <define>BOOST_UNORDERED_FOA_TESTS : foa_constructor_tests ;
 run unordered/copy_tests.cpp ;
 run unordered/move_tests.cpp ;
 run unordered/assign_tests.cpp ;
diff --git a/test/unordered/constructor_tests.cpp b/test/unordered/constructor_tests.cpp
index c2a43283..2b9d3d17 100644
--- a/test/unordered/constructor_tests.cpp
+++ b/test/unordered/constructor_tests.cpp
@@ -1,14 +1,20 @@
 
 // Copyright 2006-2010 Daniel James.
+// Copyright (C) 2022 Christian Mazakas
 // Distributed under the Boost Software License, Version 1.0. (See accompanying
 // file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
 
+#ifdef BOOST_UNORDERED_FOA_TESTS
+#include <boost/unordered_flat_set.hpp>
+#include <boost/unordered_flat_map.hpp>
+#else
 // clang-format off
 #include "../helpers/prefix.hpp"
 #include <boost/unordered_set.hpp>
 #include <boost/unordered_map.hpp>
 #include "../helpers/postfix.hpp"
 // clang-format on
+#endif
 
 #include "../helpers/test.hpp"
 #include "../objects/test.hpp"
@@ -497,6 +503,35 @@ namespace constructor_tests {
     test::check_equivalent_keys(x);
   }
 
+  using test::default_generator;
+  using test::generate_collisions;
+  using test::limited_range;
+
+#ifdef BOOST_UNORDERED_FOA_TESTS
+  boost::unordered_flat_map<test::object, test::object, test::hash,
+    test::equal_to, std::allocator<test::object> >* test_map_std_alloc;
+
+  boost::unordered_flat_set<test::object, test::hash, test::equal_to,
+    test::allocator1<test::object> >* test_set;
+  boost::unordered_flat_map<test::object, test::object, test::hash,
+    test::equal_to, test::allocator2<test::object> >* test_map;
+
+  UNORDERED_TEST(constructor_tests1,
+    ((test_map_std_alloc)(test_set)(test_map))(
+      (default_generator)(generate_collisions)(limited_range)))
+
+  UNORDERED_TEST(constructor_tests2,
+    ((test_set)(test_map))(
+      (default_generator)(generate_collisions)(limited_range)))
+
+  UNORDERED_TEST(map_constructor_test,
+    ((test_map_std_alloc)(test_map))(
+      (default_generator)(generate_collisions)(limited_range)))
+
+  UNORDERED_TEST(no_alloc_default_construct_test,
+    ((test_set)(test_map))(
+      (default_generator)(generate_collisions)(limited_range)))
+#else
   boost::unordered_map<test::object, test::object, test::hash, test::equal_to,
     std::allocator<test::object> >* test_map_std_alloc;
 
@@ -509,10 +544,6 @@ namespace constructor_tests {
   boost::unordered_multimap<test::object, test::object, test::hash,
     test::equal_to, test::allocator1<test::object> >* test_multimap;
 
-  using test::default_generator;
-  using test::generate_collisions;
-  using test::limited_range;
-
   UNORDERED_TEST(constructor_tests1,
     ((test_map_std_alloc)(test_set)(test_multiset)(test_map)(test_multimap))(
       (default_generator)(generate_collisions)(limited_range)))
@@ -528,12 +559,17 @@ namespace constructor_tests {
   UNORDERED_TEST(no_alloc_default_construct_test,
     ((test_set)(test_multiset)(test_map)(test_multimap))(
       (default_generator)(generate_collisions)(limited_range)))
+#endif
 
 #if !defined(BOOST_NO_CXX11_HDR_INITIALIZER_LIST)
 
   UNORDERED_AUTO_TEST (test_default_initializer_list) {
     std::initializer_list<int> init;
+#ifdef BOOST_UNORDERED_FOA_TESTS
+    boost::unordered_flat_set<int> x1 = init;
+#else
     boost::unordered_set<int> x1 = init;
+#endif
     BOOST_TEST(x1.empty());
   }
 
@@ -542,7 +578,12 @@ namespace constructor_tests {
 #if !defined(BOOST_NO_CXX11_HDR_INITIALIZER_LIST)
 
   UNORDERED_AUTO_TEST (test_initializer_list) {
+#ifdef BOOST_UNORDERED_FOA_TESTS
+    boost::unordered_flat_set<int> x1 = {2, 10, 45, -5};
+#else
     boost::unordered_set<int> x1 = {2, 10, 45, -5};
+#endif
+
     BOOST_TEST(x1.find(10) != x1.end());
     BOOST_TEST(x1.find(46) == x1.end());
   }