diff --git a/include/config.h b/include/config.h
index 5f2fa4d2c..ab11a90ad 100644
--- a/include/config.h
+++ b/include/config.h
@@ -36,4 +36,14 @@
 #endif
 #endif
 
+// Compatibility definition for other projects to detect pokeemerald-expansion
+#define RHH_EXPANSION
+
+// Legacy branch-based defines included for backwards compatibility
+#ifdef RHH_EXPANSION
+    #define BATTLE_ENGINE
+    #define POKEMON_EXPANSION
+    #define ITEM_EXPANSION
+#endif
+
 #endif // GUARD_CONFIG_H
diff --git a/include/constants/battle_config.h b/include/constants/battle_config.h
index 5e9984c55..fce87bd43 100644
--- a/include/constants/battle_config.h
+++ b/include/constants/battle_config.h
@@ -1,8 +1,6 @@
 #ifndef GUARD_CONSTANTS_BATTLE_CONFIG_H
 #define GUARD_CONSTANTS_BATTLE_CONFIG_H
 
-#include "constants/expansion_branches.h"
-
 #ifndef GEN_3
     #define GEN_3 0
     #define GEN_4 1
diff --git a/include/constants/expansion_branches.h b/include/constants/expansion_branches.h
deleted file mode 100644
index 48af6bf1b..000000000
--- a/include/constants/expansion_branches.h
+++ /dev/null
@@ -1,12 +0,0 @@
-#ifndef GUARD_CONSTANTS_EXPANSION_BRANCHES_H
-#define GUARD_CONSTANTS_EXPANSION_BRANCHES_H
-
-// Branch defines: Used by other branches to detect each other.
-// Each define must be here for each of RHH's branch you have pulled.
-// e.g. If you have both the battle_engine and pokemon_expansion branch,
-//      then both BATTLE_ENGINE and POKEMON_EXPANSION must be defined here.
-#define BATTLE_ENGINE
-#define POKEMON_EXPANSION
-#define ITEM_EXPANSION
-
-#endif
diff --git a/include/constants/item_config.h b/include/constants/item_config.h
index 01b5fa358..70b4440c8 100644
--- a/include/constants/item_config.h
+++ b/include/constants/item_config.h
@@ -1,8 +1,6 @@
 #ifndef GUARD_CONSTANTS_ITEM_CONFIG_H
 #define GUARD_CONSTANTS_ITEM_CONFIG_H
 
-#include "constants/expansion_branches.h"
-
 #ifndef GEN_3
 #define GEN_3 0
 #define GEN_4 1
diff --git a/include/constants/pokemon_config.h b/include/constants/pokemon_config.h
index 077c02e33..6540b6508 100644
--- a/include/constants/pokemon_config.h
+++ b/include/constants/pokemon_config.h
@@ -1,8 +1,6 @@
 #ifndef GUARD_CONSTANTS_POKEMON_CONFIG_H
 #define GUARD_CONSTANTS_POKEMON_CONFIG_H
 
-#include "constants/expansion_branches.h"
-
 #ifndef GEN_3
 #define GEN_3 0
 #define GEN_4 1
diff --git a/include/global.h b/include/global.h
index 25b43db20..b27c1e91c 100644
--- a/include/global.h
+++ b/include/global.h
@@ -15,7 +15,6 @@
 #include "constants/pokemon.h"
 #include "constants/easy_chat.h"
 #include "constants/trainer_hill.h"
-#include "constants/expansion_branches.h"
 
 // Prevent cross-jump optimization.
 #define BLOCK_CROSS_JUMP asm("");