diff --git a/README.md b/README.md
index 2183b20..1254408 100644
--- a/README.md
+++ b/README.md
@@ -1,11 +1,11 @@
 # AWS Common Runtime PHP bindings
 
 ## Requirements
-* PHP 5.5
+* PHP 5.6+
 * CMake 3.x
-* GCC 4.4+, clang, MSVC
+* GCC 4.4+, clang 3.8+
 
-## Building
+## Building on UNIX
 ```sh
 $ phpize
 $ ./configure