diff --git a/README.md b/README.md
index 2a89a44..e0de56c 100644
--- a/README.md
+++ b/README.md
@@ -18,9 +18,8 @@ First and foremost, Callisto tries to satisfy these requirements:
  - a library that works and integrates well with Lua and its
    standard library, and is easy to use
 
-Currently Callisto only works on POSIX operating systems such as
-Linux and the BSDs (mainly because I don't have a machine running
-Windows).
+Callisto only works on POSIX-compliant operating systems such as
+Linux and the BSDs. There is no plan for a Windows port.
 
 ## Dependencies
 
diff --git a/lcallisto.h b/lcallisto.h
index 1c9e70e..8db2ae0 100644
--- a/lcallisto.h
+++ b/lcallisto.h
@@ -8,6 +8,8 @@
 
 #include <lua.h>
 
+#define LUA_USE_POSIX
+
 #define CALLISTO_VERSION_MAJOR		"0"
 #define CALLISTO_VERSION_MINOR		"1"
 #define CALLISTO_VERSION_RELEASE	"0"