diff --git a/compile.mk b/compile.mk
index bbda7652..c26cd4f2 100644
--- a/compile.mk
+++ b/compile.mk
@@ -28,20 +28,16 @@ endif
 
 # Architecture-independent flags
 ifdef ARCH_X64
-	FLAGS += -DARCH_X64
 	FLAGS += -march=nehalem
 endif
 ifdef ARCH_ARM64
-	FLAGS += -DARCH_ARM64
 	FLAGS += -march=armv8-a+fp+simd
 endif
 
 ifdef ARCH_LIN
-	FLAGS += -DARCH_LIN
 	CXXFLAGS += -Wsuggest-override
 endif
 ifdef ARCH_MAC
-	FLAGS += -DARCH_MAC
 	CXXFLAGS += -stdlib=libc++
 	LDFLAGS += -stdlib=libc++
 	MAC_SDK_FLAGS := -mmacosx-version-min=10.9
@@ -49,7 +45,6 @@ ifdef ARCH_MAC
 	LDFLAGS += $(MAC_SDK_FLAGS)
 endif
 ifdef ARCH_WIN
-	FLAGS += -DARCH_WIN
 	FLAGS += -D_USE_MATH_DEFINES
 	FLAGS += -municode
 	CXXFLAGS += -Wsuggest-override
diff --git a/include/arch.hpp b/include/arch.hpp
new file mode 100644
index 00000000..99cd27b0
--- /dev/null
+++ b/include/arch.hpp
@@ -0,0 +1,20 @@
+#pragma once
+
+// Check CPU
+#if defined __x86_64__
+	#define ARCH_X64 1
+#endif
+#if defined __aarch64__
+	#define ARCH_ARM64 1
+#endif
+
+// Check OS
+#if defined _WIN32
+	#define ARCH_WIN 1
+#endif
+#if defined __APPLE__
+	#define ARCH_MAC 1
+#endif
+#if defined __linux__
+	#define ARCH_LIN 1
+#endif
diff --git a/include/common.hpp b/include/common.hpp
index 588a325b..4f320267 100644
--- a/include/common.hpp
+++ b/include/common.hpp
@@ -15,6 +15,8 @@
 #include <string>
 #include <stdexcept>
 
+#include <arch.hpp>
+
 
 /** Attribute for deprecated functions and symbols.
 E.g.
diff --git a/include/simd/Vector.hpp b/include/simd/Vector.hpp
index 4c497b9a..df040ea3 100644
--- a/include/simd/Vector.hpp
+++ b/include/simd/Vector.hpp
@@ -1,6 +1,7 @@
 #pragma once
 #include <cstring>
 #include "common.hpp"
+#include <common.hpp>
 
 
 namespace rack {
diff --git a/include/simd/functions.hpp b/include/simd/functions.hpp
index 890f4265..3208d452 100644
--- a/include/simd/functions.hpp
+++ b/include/simd/functions.hpp
@@ -1,7 +1,6 @@
 #pragma once
 #include <simd/Vector.hpp>
 #include <simd/sse_mathfun_extension.h>
-#include <common.hpp>
 #include <math.hpp>
 
 
diff --git a/src/asset.cpp b/src/asset.cpp
index 6611239c..8c3a5123 100644
--- a/src/asset.cpp
+++ b/src/asset.cpp
@@ -1,3 +1,5 @@
+#include <arch.hpp>
+
 #if defined ARCH_MAC
 	#include <CoreFoundation/CoreFoundation.h>
 	#include <CoreServices/CoreServices.h>
diff --git a/src/plugin.cpp b/src/plugin.cpp
index f039dd07..7f607880 100644
--- a/src/plugin.cpp
+++ b/src/plugin.cpp
@@ -1,3 +1,5 @@
+#include <arch.hpp>
+
 #include <thread>
 #include <map>
 #include <stdexcept>
@@ -99,7 +101,7 @@ static InitCallback loadPluginCallback(Plugin* plugin) {
 	libraryExt = "so";
 #elif defined ARCH_WIN
 	libraryExt = "dll";
-#elif ARCH_MAC
+#elif defined ARCH_MAC
 	libraryExt = "dylib";
 #endif
 
diff --git a/src/string.cpp b/src/string.cpp
index c64052d3..128892de 100644
--- a/src/string.cpp
+++ b/src/string.cpp
@@ -1,3 +1,5 @@
+#include <arch.hpp>
+
 #include <ctime>
 #include <cctype> // for tolower and toupper
 #include <algorithm> // for transform and equal
diff --git a/src/system.cpp b/src/system.cpp
index 32fdfdd7..d4130b18 100644
--- a/src/system.cpp
+++ b/src/system.cpp
@@ -1,3 +1,5 @@
+#include <arch.hpp>
+
 #include <thread>
 #include <regex>
 #include <chrono>
@@ -701,7 +703,7 @@ std::string getStackTrace() {
 			// If regex fails, just use the raw line
 			s += line;
 		}
-#elif ARCH_MAC
+#elif defined ARCH_MAC
 		// Parse line, e.g.
 		// 1   Rack                                0x0000000002ddc3eb _mangled_symbol + 27
 		std::regex r(R"((\d+)\s+(.+?)\s+(.+?) (.*?) \+ (.+?))");
diff --git a/src/window/Window.cpp b/src/window/Window.cpp
index 19d3cd8c..b3eab079 100644
--- a/src/window/Window.cpp
+++ b/src/window/Window.cpp
@@ -1,3 +1,5 @@
+#include <arch.hpp>
+
 #include <map>
 #include <queue>
 #include <thread>