diff --git a/src/main/aciomgr/dllmain.c b/src/main/aciomgr/dllmain.c
index 2d4b6f0..9ab5aa9 100644
--- a/src/main/aciomgr/dllmain.c
+++ b/src/main/aciomgr/dllmain.c
@@ -1,6 +1,6 @@
 #include <windows.h>
 
-#include "manager.h"
+#include "manager-init.h"
 
 BOOL WINAPI DllMain(HMODULE self, DWORD reason, void *ctx)
 {
diff --git a/src/main/aciomgr/manager-init.h b/src/main/aciomgr/manager-init.h
new file mode 100644
index 0000000..b0b4b1b
--- /dev/null
+++ b/src/main/aciomgr/manager-init.h
@@ -0,0 +1,8 @@
+#ifndef ACIOMGR_MANAGER_INIT_H
+#define ACIOMGR_MANAGER_INIT_H
+
+// internal, used by DllMain
+void _aciomgr_init();
+void _aciomgr_fini();
+
+#endif
diff --git a/src/main/aciomgr/manager.c b/src/main/aciomgr/manager.c
index 6a81134..5452a95 100644
--- a/src/main/aciomgr/manager.c
+++ b/src/main/aciomgr/manager.c
@@ -4,7 +4,11 @@
 
 #include <stdatomic.h>
 
-#include "manager.h"
+#include "aciomgr/manager-init.h"
+
+#include "aciomgr/manager.h"
+
+#include "acio/acio.h"
 
 #include "aciodrv/device.h"
 #include "util/array.h"
diff --git a/src/main/aciomgr/manager.h b/src/main/aciomgr/manager.h
index fbdc632..d2127a8 100644
--- a/src/main/aciomgr/manager.h
+++ b/src/main/aciomgr/manager.h
@@ -3,19 +3,14 @@
 
 #include <stdbool.h>
 
-#include "acio/acio.h"
-
 #include "bemanitools/glue.h"
 
 #define ACIOMGR_NODE_PRODUCT_CODE_LEN 4
 
+struct ac_io_message;
 struct aciodrv_device_ctx;
 struct aciomgr_port_dispatcher;
 
-// internal
-void _aciomgr_init();
-void _aciomgr_fini();
-
 /**
  * The first function that will be called on your DLL. You will be supplied
  * with four function pointers that may be used to log messages to the game's
@@ -88,4 +83,4 @@ aciomgr_port_checkout(struct aciomgr_port_dispatcher *dispatcher);
  */
 void aciomgr_port_checkin(struct aciomgr_port_dispatcher *dispatcher);
 
-#endif
\ No newline at end of file
+#endif