diff --git a/README.md b/README.md
index 8abe12f..93161fc 100644
--- a/README.md
+++ b/README.md
@@ -2,6 +2,8 @@
 
 ## How to build
 
+Assumes git, ninja, cmake, gcc or clang. If under msys2 use ucrt64.
+
 protobuf is required. Use the same compiler for protobuf and mesytec-mnode.
 
 ```bash