diff --git a/src/nix/main.cc b/src/nix/main.cc
index 20d3ea5c2..2005ec5f9 100644
--- a/src/nix/main.cc
+++ b/src/nix/main.cc
@@ -16,6 +16,7 @@ struct NixArgs : virtual MultiCommand, virtual MixCommonArgs
     {
         mkFlag('h', "help", "show usage information", [=]() {
             printHelp(programName, std::cout);
+            std::cout << "\nNote: this program is EXPERIMENTAL and subject to change.\n";
             throw Exit();
         });