diff --git a/README.md b/README.md
index 0801e10..dcdd778 100644
--- a/README.md
+++ b/README.md
@@ -24,6 +24,7 @@ Built for and tested on **Windows 10 version 1507 (or newer) x64/ARM64**. 32-Bit
   - I do not want to force any consumer of the library to drag C++ paradigms into their project. I do expect the user to utilize a modern compiler though, so the library sources themselves may have some 'C++-ish touches' here and there, for my own convenience 😉
 - Compatibility with every Windows 10 version.
   - APIs not available on older builds will give you a `STATUS_NOT_IMPLEMENTED` instead of hard-linking and therefore making your driver fail to load 🤞
+    - **Caution:** this claim comes with an asterisk though; due to PatchGuard (or some other security mechanism) I couldn't get run-time dynamic linking for `ci.dll` exports to work, so you need to actively avoid implementing code depending on exports that do not exist on earlier versions of Windows. Once I have a compatibility matrix for all of them I'll update the documentation accordingly.
 - No conflicts with WDF or DMF
   - The consuming driver *may* (but doesn't have to) utilize Microsoft WDF or DMF in addition without having to fear any incompatibilities 💪
 - Reliable SAL annotations.