diff --git a/server/CMakeLists.txt b/server/CMakeLists.txt
index 24c912c1..e391a5e5 100644
--- a/server/CMakeLists.txt
+++ b/server/CMakeLists.txt
@@ -23,7 +23,7 @@ endif()
 
 add_executable(traintastic-server src/main.cpp src/options.hpp)
 add_dependencies(traintastic-server traintastic-lang)
-set_target_properties(traintastic-server PROPERTIES CXX_STANDARD 17)
+set_target_properties(traintastic-server PROPERTIES CXX_STANDARD 20)
 target_include_directories(traintastic-server PRIVATE
   ${CMAKE_CURRENT_BINARY_DIR}
   ../shared/src)
@@ -34,14 +34,17 @@ target_include_directories(traintastic-server SYSTEM PRIVATE
 if(BUILD_TESTING)
   add_subdirectory(thirdparty/catch2)
   set_target_properties(Catch2 PROPERTIES
-    CXX_STANDARD 17
+    CXX_STANDARD 20
     CXX_CLANG_TIDY ""
   )
+  if(CMAKE_CXX_COMPILER_ID STREQUAL "GNU")
+    target_compile_options(Catch2 PRIVATE -Wno-restrict) # workaround GCC bug
+  endif()
   add_executable(traintastic-server-test test/main.cpp)
   add_dependencies(traintastic-server-test traintastic-lang)
   target_compile_definitions(traintastic-server-test PRIVATE -DTRAINTASTIC_TEST)
   set_target_properties(traintastic-server-test PROPERTIES
-    CXX_STANDARD 17
+    CXX_STANDARD 20
     CXX_CLANG_TIDY ""
   )
   target_include_directories(traintastic-server-test PRIVATE
diff --git a/server/src/hardware/decoder/decoderfunctions.cpp b/server/src/hardware/decoder/decoderfunctions.cpp
index 3e790c07..2bde88b4 100644
--- a/server/src/hardware/decoder/decoderfunctions.cpp
+++ b/server/src/hardware/decoder/decoderfunctions.cpp
@@ -44,7 +44,7 @@ DecoderFunctions::DecoderFunctions(Object& _parent, std::string_view parentPrope
         }
 
         auto function = std::make_shared<DecoderFunction>(decoder, number);
-        function->name = "F" + std::to_string(number);
+        function->name = std::to_string(number).insert(0, 1, 'F');
         function->number = number;
         if(number == 0) // F0 is (almost) always the light function
           function->function = DecoderFunctionFunction::Light;