diff --git a/.gitignore b/.gitignore
index 4bb62e0c..1c467992 100644
--- a/.gitignore
+++ b/.gitignore
@@ -256,3 +256,4 @@ build-test-Desktop_x86_windows_msvc2017_pe_32bit-Debug
 test/Logs
 build-test-Desktop_x86_windows_msvc2019_pe_32bit-Debug
 test/vs2019/.vs
+Corel Auto-Preserve
diff --git a/etl-patreon.png b/etl-patreon.png
new file mode 100644
index 00000000..5f2a68c3
Binary files /dev/null and b/etl-patreon.png differ
diff --git a/etl-social.png b/etl-social.png
new file mode 100644
index 00000000..a9082edb
Binary files /dev/null and b/etl-social.png differ
diff --git a/include/etl/generators/type_traits_generator.h b/include/etl/generators/type_traits_generator.h
index 81196e02..77aec58a 100644
--- a/include/etl/generators/type_traits_generator.h
+++ b/include/etl/generators/type_traits_generator.h
@@ -114,6 +114,9 @@ namespace etl
 #if ETL_CPP11_SUPPORTED
   template <bool B>
   using bool_constant = integral_constant<bool, B>;
+#else
+  template <bool B>
+  struct bool_constant : etl::integral_constant<bool, B> { };
 #endif
 
   //***************************************************************************
@@ -799,6 +802,9 @@ namespace etl
 #if ETL_CPP17_SUPPORTED
   template <bool B>
   using bool_constant = std::bool_constant<B>;
+#else
+  template <bool B>
+  struct bool_constant : std::integral_constant<bool, B> { };
 #endif
 
   //***************************************************************************
diff --git a/include/etl/type_traits.h b/include/etl/type_traits.h
index b4475a5a..753f8122 100644
--- a/include/etl/type_traits.h
+++ b/include/etl/type_traits.h
@@ -102,6 +102,9 @@ namespace etl
 #if ETL_CPP11_SUPPORTED
   template <bool B>
   using bool_constant = integral_constant<bool, B>;
+#else
+  template <bool B>
+  struct bool_constant : etl::integral_constant<bool, B> { };
 #endif
 
   //***************************************************************************
@@ -787,6 +790,9 @@ namespace etl
 #if ETL_CPP17_SUPPORTED
   template <bool B>
   using bool_constant = std::bool_constant<B>;
+#else
+  template <bool B>
+  struct bool_constant : std::integral_constant<bool, B> { };
 #endif
 
   //***************************************************************************
diff --git a/include/etl/version.h b/include/etl/version.h
index 129be118..8ac0d3ae 100644
--- a/include/etl/version.h
+++ b/include/etl/version.h
@@ -39,7 +39,7 @@ SOFTWARE.
 
 #define ETL_VERSION_MAJOR 18
 #define ETL_VERSION_MINOR  3
-#define ETL_VERSION_PATCH  0
+#define ETL_VERSION_PATCH  1
 #define ETL_VERSION       ETL_STRINGIFY(ETL_VERSION_MAJOR) "." ETL_STRINGIFY(ETL_VERSION_MINOR) "." ETL_STRINGIFY(ETL_VERSION_PATCH)
 #define ETL_VERSION_W     ETL_STRINGIFY(ETL_VERSION_MAJOR) L"." ETL_STRINGIFY(ETL_VERSION_MINOR) L"." ETL_STRINGIFY(ETL_VERSION_PATCH)
 #define ETL_VERSION_U16   ETL_STRINGIFY(ETL_VERSION_MAJOR) u"." ETL_STRINGIFY(ETL_VERSION_MINOR) u"." ETL_STRINGIFY(ETL_VERSION_PATCH)
diff --git a/library.json b/library.json
index 3cc77423..c4b2d56f 100644
--- a/library.json
+++ b/library.json
@@ -1,6 +1,6 @@
 {
   "name": "Embedded Template Library",
-  "version": "18.3.0",
+  "version": "18.3.1",
   "authors": {
     "name": "John Wellbelove",
     "email": "john.wellbelove@etlcpp.com"
diff --git a/library.properties b/library.properties
index 50f72707..2b0093c5 100644
--- a/library.properties
+++ b/library.properties
@@ -1,5 +1,5 @@
 name=Embedded Template Library
-version=18.3.0
+version=18.3.1
 author= John Wellbelove <john.wellbelove@etlcpp.com>
 maintainer=John Wellbelove <john.wellbelove@etlcpp.com>
 license=MIT
diff --git a/support/Release notes.txt b/support/Release notes.txt
index 8c07ddce..11160bb0 100644
--- a/support/Release notes.txt	
+++ b/support/Release notes.txt	
@@ -1,3 +1,7 @@
+===============================================================================
+18.3.1
+C++03 compatibility fix for type_traits.h
+
 ===============================================================================
 18.3.0
 Added etl::parameter_pack to easily extract information about the types in a 
diff --git a/test/test_type_traits.cpp b/test/test_type_traits.cpp
index 28127d17..db25c33c 100644
--- a/test/test_type_traits.cpp
+++ b/test/test_type_traits.cpp
@@ -737,7 +737,7 @@ namespace
   };
 
   //*************************************************************************
-  TEST(conditional_integral_constant)
+  TEST(test_conditional_integral_constant)
   {
     int v1 = etl::conditional_integral_constant<true,  int, 1, 2>::value;
     int v2 = etl::conditional_integral_constant<false, int, 1, 2>::value;
@@ -747,7 +747,7 @@ namespace
   }
 
   //*************************************************************************
-  TEST(size_of)
+  TEST(test_size_of)
   {
     CHECK_EQUAL(1, etl::size_of<void>::value);
     CHECK_EQUAL(1, etl::size_of<char>::value);
@@ -763,7 +763,7 @@ namespace
   }
 
   //*************************************************************************
-  TEST(is_convertible)
+  TEST(test_is_convertible)
   {
     CHECK((etl::is_convertible<char, int>::value));
     CHECK((etl::is_convertible<int,  char>::value));
@@ -779,7 +779,7 @@ namespace
   }
 
   //*************************************************************************
-  TEST(add_lvalue_reference)
+  TEST(test_add_lvalue_reference)
   {
     CHECK(!std::is_lvalue_reference_v<etl::add_lvalue_reference<void>::type>);
     CHECK(std::is_lvalue_reference_v<etl::add_lvalue_reference<int>::type>);
@@ -789,7 +789,7 @@ namespace
   }
 
   //*************************************************************************
-  TEST(add_rvalue_reference)
+  TEST(test_add_rvalue_reference)
   {
     CHECK(!std::is_rvalue_reference_v<etl::add_rvalue_reference<void>::type>);
     CHECK(std::is_rvalue_reference_v<etl::add_rvalue_reference<int>::type>);
@@ -799,7 +799,7 @@ namespace
   }
 
   //*************************************************************************
-  TEST(is_lvalue_reference)
+  TEST(test_is_lvalue_reference)
   {
     CHECK_EQUAL(std::is_lvalue_reference_v<void>,  etl::is_lvalue_reference_v<void>);
     CHECK_EQUAL(std::is_lvalue_reference_v<int>,   etl::is_lvalue_reference_v<int>);
@@ -809,7 +809,7 @@ namespace
   }
 
   //*************************************************************************
-  TEST(is_rvalue_reference)
+  TEST(test_is_rvalue_reference)
   {
     CHECK_EQUAL(std::is_rvalue_reference_v<void>,  etl::is_rvalue_reference_v<void>);
     CHECK_EQUAL(std::is_rvalue_reference_v<int>,   etl::is_rvalue_reference_v<int>);
@@ -817,4 +817,19 @@ namespace
     CHECK_EQUAL(std::is_rvalue_reference_v<int&>,  etl::is_rvalue_reference_v<int&>);
     CHECK_EQUAL(std::is_rvalue_reference_v<int&&>, etl::is_rvalue_reference_v<int&&>);
   }
+
+  //*************************************************************************
+  TEST(test_integral_constants)
+  {
+    CHECK_EQUAL(1, (etl::integral_constant<int, 1>::value));
+    CHECK((std::is_same_v<int, etl::integral_constant<int, 1>::value_type>));
+
+    CHECK_EQUAL(false, (etl::bool_constant<false>::value));
+    CHECK_EQUAL(true, (etl::bool_constant<true>::value));
+    CHECK((std::is_same_v<bool, etl::bool_constant<true>::value_type>));
+
+    CHECK_EQUAL(true, etl::negation_v<etl::bool_constant<false>>);
+    CHECK_EQUAL(false, etl::negation_v<etl::bool_constant<true>>);
+    CHECK((std::is_same_v<bool, etl::bool_constant<true>::value_type>));
+  }
 }