diff --git a/CMakeLists.txt b/CMakeLists.txt
index 8b5c7e8..45e22e3 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -21,7 +21,7 @@ target_link_libraries(simple-web-server INTERFACE ${CMAKE_THREAD_LIBS_INIT})
 # TODO 2020 when Debian Jessie LTS ends:
 # Remove Boost system, thread, regex components; use Boost::<component> aliases; remove Boost target_include_directories
 if(USE_STANDALONE_ASIO)
-    target_compile_definitions(simple-web-server INTERFACE USE_STANDALONE_ASIO)
+    target_compile_definitions(simple-web-server INTERFACE ASIO_STANDALONE)
     find_path(ASIO_PATH asio.hpp)
     if(NOT ASIO_PATH)
         message(FATAL_ERROR "Standalone Asio not found")
diff --git a/asio_compatibility.hpp b/asio_compatibility.hpp
index c2e0b66..5a7007d 100644
--- a/asio_compatibility.hpp
+++ b/asio_compatibility.hpp
@@ -3,7 +3,7 @@
 
 #include <memory>
 
-#ifdef USE_STANDALONE_ASIO
+#ifdef ASIO_STANDALONE
 #include <asio.hpp>
 #include <asio/steady_timer.hpp>
 namespace SimpleWeb {
@@ -27,7 +27,7 @@ namespace SimpleWeb {
 #endif
 
 namespace SimpleWeb {
-#if(USE_STANDALONE_ASIO && ASIO_VERSION >= 101300) || BOOST_ASIO_VERSION >= 101300
+#if(ASIO_STANDALONE && ASIO_VERSION >= 101300) || BOOST_ASIO_VERSION >= 101300
   using io_context = asio::io_context;
   using resolver_results = asio::ip::tcp::resolver::results_type;
   using async_connect_endpoint = asio::ip::tcp::endpoint;
diff --git a/client_http.hpp b/client_http.hpp
index fb1fb23..3a08473 100644
--- a/client_http.hpp
+++ b/client_http.hpp
@@ -50,14 +50,14 @@ namespace SimpleWeb {
     }
   };
 } // namespace SimpleWeb
-#ifndef USE_STANDALONE_ASIO
+#ifndef ASIO_STANDALONE
 namespace boost {
 #endif
   namespace asio {
     template <>
     struct is_match_condition<SimpleWeb::HeaderEndMatch> : public std::true_type {};
   } // namespace asio
-#ifndef USE_STANDALONE_ASIO
+#ifndef ASIO_STANDALONE
 } // namespace boost
 #endif
 
diff --git a/client_https.hpp b/client_https.hpp
index aabca1c..c6655f1 100644
--- a/client_https.hpp
+++ b/client_https.hpp
@@ -3,7 +3,7 @@
 
 #include "client_http.hpp"
 
-#ifdef USE_STANDALONE_ASIO
+#ifdef ASIO_STANDALONE
 #include <asio/ssl.hpp>
 #else
 #include <boost/asio/ssl.hpp>
diff --git a/server_https.hpp b/server_https.hpp
index dc2476b..48ae673 100644
--- a/server_https.hpp
+++ b/server_https.hpp
@@ -3,7 +3,7 @@
 
 #include "server_http.hpp"
 
-#ifdef USE_STANDALONE_ASIO
+#ifdef ASIO_STANDALONE
 #include <asio/ssl.hpp>
 #else
 #include <boost/asio/ssl.hpp>
diff --git a/utility.hpp b/utility.hpp
index 3b41ff3..d9119de 100644
--- a/utility.hpp
+++ b/utility.hpp
@@ -27,7 +27,7 @@
 namespace SimpleWeb {
   using string_view = std::string_view;
 }
-#elif !defined(USE_STANDALONE_ASIO)
+#elif !defined(ASIO_STANDALONE)
 #include <boost/utility/string_ref.hpp>
 namespace SimpleWeb {
   using string_view = boost::string_ref;