diff --git a/BUILD.md b/BUILD.md
index 49bc096..06aa293 100644
--- a/BUILD.md
+++ b/BUILD.md
@@ -57,6 +57,14 @@ as submodules. The result will not be installable on the system without this rep
 remaining intact. Please read the compatibility primer first to understand which options
 you need or don't need on your system.
 
+##### Re-building
+When you want to recompile and your system had changes (upgraded libs, compiler, switching between clang and gcc, etc.) you are advised to start from a clean state:
+
+```
+git reset --hard  &&  git clean -f -x -d
+./autogen.sh
+./configure --prefix=...
+```
 
 ### Additional build options