diff --git a/ext/texplay/bindings.c b/ext/texplay/bindings.c
index 9475f4f..0775063 100644
--- a/ext/texplay/bindings.c
+++ b/ext/texplay/bindings.c
@@ -308,7 +308,7 @@ m_clone_image(VALUE self)
 
     cloned_image = m_dup_image(self);
 
-    #if RUBY_API_VERSION_MAJOR <= 1 || (RUBY_API_VERSION_MAJOR == 2 && RUBY_API_VERSION_MINOR >= 0)
+    #if RUBY_API_VERSION_MAJOR <= 1 || (RUBY_API_VERSION_MAJOR >= 2)
         /* the main diff b/w clone and dup is that clone also dups the singleton */
         rb_obj_reveal(cloned_image, rb_singleton_class_clone(self));
     #else
diff --git a/ext/texplay/texplay.h b/ext/texplay/texplay.h
index ef32c1b..904bbd5 100644
--- a/ext/texplay/texplay.h
+++ b/ext/texplay/texplay.h
@@ -28,9 +28,13 @@
 #define ABS(X) ((X) >= 0 ? (X) : -(X))
 
 /* enums */
+#ifdef __bool_true_false_are_defined
+/* Newer Ruby versions already include stdbool.h */
+#else
 typedef enum e_bool {
   false, true
 } bool;
+#endif
 
 typedef enum e_color {
   red, green, blue, alpha