--- src/enchant.h
+++ src/enchant.h
@@ -34,6 +34,10 @@
 #include <stdint.h> /* for uint32_t */
 #include <sys/types.h> /* for size_t, ssize_t */
 
+#ifdef _WIN32
+# include <BaseTsd.h>
+# define ssize_t SSIZE_T
+#endif
 
 #ifdef __cplusplus
 extern "C" {