diff --git a/engine/common/build.c b/engine/common/build.c
index c4ddaeeb..42ba572c 100644
--- a/engine/common/build.c
+++ b/engine/common/build.c
@@ -95,6 +95,8 @@ const char *Q_buildos( void )
osname = "DOS4GW";
#elif XASH_HAIKU
osname = "haiku";
+#elif XASH_SERENITY
+ osname = "serenityos";
#else
#error "Place your operating system name here! If this is a mistake, try to fix conditions above and report a bug"
#endif
diff --git a/public/build.h b/public/build.h
index 6e1f326d..57a7735f 100644
--- a/public/build.h
+++ b/public/build.h
@@ -74,6 +74,7 @@ For more information, please refer to
#undef XASH_RISCV_DOUBLEFP
#undef XASH_RISCV_SINGLEFP
#undef XASH_RISCV_SOFTFP
+#undef XASH_SERENITY
#undef XASH_WIN32
#undef XASH_WIN64
#undef XASH_X86
@@ -125,6 +126,9 @@ For more information, please refer to
#elif defined __HAIKU__
#define XASH_HAIKU 1
#define XASH_POSIX 1
+#elif defined __serenity__
+ #define XASH_SERENITY 1
+ #define XASH_POSIX 1
#else
#error "Place your operating system name here! If this is a mistake, try to fix conditions above and report a bug"
#endif