diff --git a/doc/performance.md b/doc/performance.md
index c3bf7a96..5b3d5ff1 100644
--- a/doc/performance.md
+++ b/doc/performance.md
@@ -156,8 +156,12 @@ On Intel and AMD Windows platforms, Microsoft Visual Studio enables programmers
 
 We do not recommend that you compile simdjson with architecture-specific flags such as  `arch:AVX2`. The simdjson library automatically selects the best execution kernel at runtime.
 
+When compiling with Visual Studio, we recommend the flags `/Ob2 /O2`. Weaker optimizations flags (e.g., `/Ox` alone) are inadequate.
+
 Recent versions of Microsoft Visual Studio on Windows provides support for the LLVM Clang compiler. You  only need to install the "Clang compiler" optional component. You may also get a copy of the 64-bit LLVM CLang compiler for [Windows directly from LLVM](https://releases.llvm.org/download.html). The simdjson library fully supports the LLVM Clang compiler under Windows. In fact, you may get better performance out of simdjson with the LLVM Clang compiler than with the regular Visual Studio compiler.
 
+In our experience, you will get much better performance compiling with GNU GCC under Windows via MSYS2. If that is a possibility, you should consider it.
+
 
 Downclocking
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