diff --git a/src/binary/object.cpp b/src/binary/object.cpp
index 0920e428..7f4d524f 100644
--- a/src/binary/object.cpp
+++ b/src/binary/object.cpp
@@ -5,6 +5,7 @@
 #include "binary/module_base.hpp"
 
 #include <string>
+#include <system_error>
 #include <vector>
 #include <mutex>
 #include <unordered_map>
@@ -16,7 +17,9 @@
   #include <link.h> // needed for dladdr1's link_map info
  #endif
 #elif IS_WINDOWS
- #define WIN32_LEAN_AND_MEAN
+ #ifndef WIN32_LEAN_AND_MEAN
+  #define WIN32_LEAN_AND_MEAN
+ #endif
  #include <windows.h>
 #endif
 
diff --git a/src/binary/pe.cpp b/src/binary/pe.cpp
index 107084a3..dc0b728a 100644
--- a/src/binary/pe.cpp
+++ b/src/binary/pe.cpp
@@ -10,7 +10,9 @@
 #include <cstring>
 #include <string>
 
-#define WIN32_LEAN_AND_MEAN
+#ifndef WIN32_LEAN_AND_MEAN
+ #define WIN32_LEAN_AND_MEAN
+#endif
 #include <windows.h>
 
 namespace cpptrace {
diff --git a/src/demangle/demangle_with_winapi.cpp b/src/demangle/demangle_with_winapi.cpp
index 6bfd5763..5d702c4a 100644
--- a/src/demangle/demangle_with_winapi.cpp
+++ b/src/demangle/demangle_with_winapi.cpp
@@ -4,7 +4,9 @@
 
 #include <string>
 
-#define WIN32_LEAN_AND_MEAN
+#ifndef WIN32_LEAN_AND_MEAN
+ #define WIN32_LEAN_AND_MEAN
+#endif
 #include <windows.h>
 #include <dbghelp.h>
 
diff --git a/src/from_current.cpp b/src/from_current.cpp
index d45c5512..d099a76c 100644
--- a/src/from_current.cpp
+++ b/src/from_current.cpp
@@ -11,7 +11,9 @@
 #ifndef _MSC_VER
  #include <string.h>
  #if IS_WINDOWS
-  #define WIN32_LEAN_AND_MEAN
+  #ifndef WIN32_LEAN_AND_MEAN
+   #define WIN32_LEAN_AND_MEAN
+  #endif
   #include <windows.h>
  #else
   #include <sys/mman.h>
diff --git a/src/platform/dbghelp_syminit_manager.cpp b/src/platform/dbghelp_syminit_manager.cpp
index 774db78b..e11f8667 100644
--- a/src/platform/dbghelp_syminit_manager.cpp
+++ b/src/platform/dbghelp_syminit_manager.cpp
@@ -9,7 +9,9 @@
 
 #include <unordered_set>
 
-#define WIN32_LEAN_AND_MEAN
+#ifndef WIN32_LEAN_AND_MEAN
+ #define WIN32_LEAN_AND_MEAN
+#endif
 #include <windows.h>
 #include <dbghelp.h>
 
diff --git a/src/platform/path.hpp b/src/platform/path.hpp
index afb6775e..849ad663 100644
--- a/src/platform/path.hpp
+++ b/src/platform/path.hpp
@@ -7,7 +7,9 @@
 #include <cctype>
 
 #if IS_WINDOWS
-#define WIN32_LEAN_AND_MEAN
+#ifndef WIN32_LEAN_AND_MEAN
+ #define WIN32_LEAN_AND_MEAN
+#endif
 #include <windows.h>
 #endif
 
diff --git a/src/platform/program_name.hpp b/src/platform/program_name.hpp
index 7d22cda6..e5dafac3 100644
--- a/src/platform/program_name.hpp
+++ b/src/platform/program_name.hpp
@@ -7,7 +7,9 @@
 #include "platform/platform.hpp"
 
 #if IS_WINDOWS
-#define WIN32_LEAN_AND_MEAN
+#ifndef WIN32_LEAN_AND_MEAN
+ #define WIN32_LEAN_AND_MEAN
+#endif
 #include <windows.h>
 
 #define CPPTRACE_MAX_PATH MAX_PATH
diff --git a/src/symbols/symbols_with_dbghelp.cpp b/src/symbols/symbols_with_dbghelp.cpp
index 7bb05e2b..0e665a9b 100644
--- a/src/symbols/symbols_with_dbghelp.cpp
+++ b/src/symbols/symbols_with_dbghelp.cpp
@@ -12,7 +12,9 @@
 #include <system_error>
 #include <vector>
 
-#define WIN32_LEAN_AND_MEAN
+#ifndef WIN32_LEAN_AND_MEAN
+ #define WIN32_LEAN_AND_MEAN
+#endif
 #include <windows.h>
 #include <dbghelp.h>
 
diff --git a/src/unwind/unwind_with_winapi.cpp b/src/unwind/unwind_with_winapi.cpp
index 75ec5a1d..2dd59b34 100644
--- a/src/unwind/unwind_with_winapi.cpp
+++ b/src/unwind/unwind_with_winapi.cpp
@@ -9,7 +9,9 @@
 #include <cstdint>
 #include <vector>
 
-#define WIN32_LEAN_AND_MEAN
+#ifndef WIN32_LEAN_AND_MEAN
+ #define WIN32_LEAN_AND_MEAN
+#endif
 #include <windows.h>
 
 // Fucking windows headers
diff --git a/src/utils/utils.cpp b/src/utils/utils.cpp
index 80de3440..4a2061e3 100644
--- a/src/utils/utils.cpp
+++ b/src/utils/utils.cpp
@@ -2,7 +2,9 @@
 
 #if IS_WINDOWS
  #include <io.h>
- #define WIN32_LEAN_AND_MEAN
+ #ifndef WIN32_LEAN_AND_MEAN
+  #define WIN32_LEAN_AND_MEAN
+ #endif
  #include <windows.h>
 #else
  #include <sys/stat.h>