diff --git a/README.md b/README.md
index 0d06a55..00ee54c 100644
--- a/README.md
+++ b/README.md
@@ -27,4 +27,13 @@ to support these builtins. So far the 2 above-mentioned compilers support them
 MSVC++ is currently unsupported. It is likely that it will never be supported,
 as it seems that MS will start supporting Clang in Visual Studio; however,
 if that does not happen and the MS C++ compiler gains the required features,
-support will be added.
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+support will be added.
+
+## Supported operating systems
+
+Currently supported OSes in OctaSTD are Linux, FreeBSD and OS X. Other
+systems that implement POSIX API will also work (if they don't, bug reports
+are welcome).
+
+Windows is supported at least with the MinGW (gcc) and Clang compilers. MS
+Visual Studio is currently unsupported.
\ No newline at end of file