diff --git a/io.h b/io.h
index c27344b7f..dc69eb2e3 100644
--- a/io.h
+++ b/io.h
@@ -43,6 +43,12 @@ enum ethash_io_rc {
 	ETHASH_IO_MEMO_MATCH,         ///< DAG file existed and revision/hash matched. No need to do anything
 };
 
+// small hack for windows. I don't feel I should use va_args and forward just
+// to have this one function properly cross-platform abstracted
+#if defined(_WIN32)
+#define snprintf(...) sprintf_s(__VA_ARGS__)
+#endif
+
 /**
  * Prepares io for ethash
  *
diff --git a/io_win32.c b/io_win32.c
index 9906c359e..6fdfec28b 100644
--- a/io_win32.c
+++ b/io_win32.c
@@ -23,6 +23,8 @@
 #include <direct.h>
 #include <errno.h>
 #include <stdio.h>
+#include <sys/stat.h>
+#include <sys/types.h>
 
 FILE *ethash_fopen(const char *file_name, const char *mode)
 {
diff --git a/mmap.h b/mmap.h
index 17f145888..1eed116a9 100644
--- a/mmap.h
+++ b/mmap.h
@@ -20,8 +20,26 @@
  */
 #pragma once
 #if defined(__MINGW32__) || defined(_WIN32)
-void *mmap(void *start, size_t length, int prot, int flags, int fd, off_t offset);
+#include <sys/types.h>
+
+#define PROT_READ     0x1
+#define PROT_WRITE    0x2
+/* This flag is only available in WinXP+ */
+#ifdef FILE_MAP_EXECUTE
+#define PROT_EXEC     0x4
 #else
+#define PROT_EXEC        0x0
+#define FILE_MAP_EXECUTE 0
+#endif
+
+#define MAP_SHARED    0x01
+#define MAP_PRIVATE   0x02
+#define MAP_ANONYMOUS 0x20
+#define MAP_ANON      MAP_ANONYMOUS
+#define MAP_FAILED    ((void *) -1)
+
+void *mmap(void *start, size_t length, int prot, int flags, int fd, off_t offset);
+#else // posix, yay! ^_^
 #include <sys/mman.h>
 #endif
 
diff --git a/mmap_win32.c b/mmap_win32.c
index 9a37b6c79..3d2a04133 100644
--- a/mmap_win32.c
+++ b/mmap_win32.c
@@ -13,25 +13,8 @@
 
 #include <io.h>
 #include <windows.h>
-#include <sys/types.h>
 #include "mmap.h"
 
-#define PROT_READ     0x1
-#define PROT_WRITE    0x2
-/* This flag is only available in WinXP+ */
-#ifdef FILE_MAP_EXECUTE
-#define PROT_EXEC     0x4
-#else
-#define PROT_EXEC        0x0
-#define FILE_MAP_EXECUTE 0
-#endif
-
-#define MAP_SHARED    0x01
-#define MAP_PRIVATE   0x02
-#define MAP_ANONYMOUS 0x20
-#define MAP_ANON      MAP_ANONYMOUS
-#define MAP_FAILED    ((void *) -1)
-
 #ifdef __USE_FILE_OFFSET64
 # define DWORD_HI(x) (x >> 32)
 # define DWORD_LO(x) ((x) & 0xffffffff)